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Commentary

Immunomodulatory Potential of Non-Classical HLA-G in Infections including COVID-19 and Parasitic Diseases

1
Department of Parasitology and Mycology, School of Medicine, Shiraz University of Medical Sciences, Shiraz 7134845794, Iran
2
Infectious and Tropical Diseases Group (E-INTRO), Institute of Biomedical Research of Salamanca-Research Center for Tropical Diseases (IBSAL-CIETUS), Faculty of Pharmacy, University of Salamanca, 37008 Salamanca, Spain
3
Parasite Biology Group, ICGEB, Aruna Asaf Ali Marg, New Delhi 110067, India
4
Department of Immunology, Faculty of Medicine, Shahid Sadoughi University of Medical Sciences and Health Services, Yazd 8915173143, Iran
5
Department of Immunology, School of Medicine, Jiroft University of Medical Sciences, Jiroft 7861615765, Iran
6
Department of Microbiology and Parasitology, ISTUN Institute of Tropical Health, IdiSNA (Navarra Institute for Health Research), University of Navarra, c/ Irunlarrea 1, 31008 Pamplona, Spain
*
Authors to whom correspondence should be addressed.
Biomolecules 2022, 12(2), 257; https://doi.org/10.3390/biom12020257
Submission received: 7 December 2021 / Revised: 23 January 2022 / Accepted: 31 January 2022 / Published: 4 February 2022

Abstract

:
Human Leukocyte Antigen-G (HLA-G), a polymorphic non-classical HLA (HLA-Ib) with immune-regulatory properties in cancers and infectious diseases, presents both membrane-bound and soluble (sHLA-G) isoforms. Polymorphism has implications in host responses to pathogen infections and in pathogenesis. Differential expression patterns of HLA-G/sHLA-G or its polymorphism seem to be related to different pathological conditions, potentially acting as a disease progression biomarker. Pathogen antigens might be involved in the regulation of both membrane-bound and sHLA-G levels and impact immune responses during co-infections. The upregulation of HLA-G in viral and bacterial infections induce tolerance to infection. Recently, sHLA-G was found useful to identify the prognosis of Coronavirus disease 2019 (COVID-19) among patients and it was observed that the high levels of sHLA-G are associated with worse prognosis. The use of pathogens, such as Plasmodium falciparum, as immune modulators for other infections could be extended for the modulation of membrane-bound HLA-G in COVID-19-infected tissues. Overall, such information might open new avenues concerning the effect of some pathogens such as parasites in decreasing the expression level of HLA-G to restrict pathogenesis in some infections or to influence the immune responses after vaccination among others.

1. Introduction

Major Histocompatibility Complex (MHC or the synonymous HLA, Human Leucocyte Antigens) has three regions designated as Class I, Class II, and Class III, and genes belonging to each of them encode the synthesis of molecules with different structure and function. The main function of class I gene products is the presentation of endogenous peptide antigens to CD8+ T cells. The HLA-I molecules are classified into classical HLA-Ia (HLA-A, B, and C) and non-classical HLA-Ib (HLA-E, F, and G). The classical molecules show high polymorphism and are characterized by unique patterns of transcription, protein structure, and immunological function. Non-classical MHC-I molecules exert functions in both the innate and adaptive immune system and, compared to classical MHC-I, appear to have mostly inhibitory effects on immune cells via interaction with inhibitory receptors [1].
HLA-G plays a major role in the down-regulation of the functions of the innate and adaptive immune system cells through interaction with multiple inhibitory receptors such as Leukocyte Immunoglobin-Like Receptors (LILRs) and in the presentation of non-peptidic antigens to non-classical T cells, leading to unique and fast immune responses upon infections [2]. The origin, structure, and functions of this molecule have been recently published. As of September 2020, the IMGT-HLA database includes 80 HLA-G alleles, encoding 21 complete and 4 truncated proteins (HLA-G1*01:05N, G*01:13N, G*01:21N and G*01:25N) [3,4]. Four membrane-bound (HLA-G1-4) and three soluble HLA-G isoforms (sHLA-G5-7) have been identified, each with different globular domains, mainly α1, α2, α3, and a beta-2-microglobulin (β2M) in HLA-G1 and HLA-G5 isoforms, the most important ones [5,6]. HLA-G1 isoform is found in soluble form due to proteases shedding. Their potential to dimerize plays important physiological roles for both soluble and membrane-bound HLA-Gs including higher affinity and avidity for their corresponding inhibitory receptors. Specially, the HLA-G1 homodimer orientation and the presence or absence of β2M-free isoforms appear essential to provide the required plasticity and/or flexibility of the complex states [7]. HLA-G does not seem to initiate immune responses as its classical homologues. In addition, a number of studies have highlighted the important role of this immune checkpoint molecule in the modulation of the immune system in immune-related diseases, tumors, and infections through the structure and dynamics of the different HLA-G isoforms [8,9,10,11].
HLA-G is mainly expressed in the placenta, in embryonic tissues, in adult immune-privileged organs, and in cells of the hematopoietic lineage. HLA-G-positive (HLA-G+) CD4+ and CD8+ T lymphocytes, monocytes, and Natural Killer (NK) and dendritic cells are also detected in some patients with pathological disorders [12]. The molecule has a particular conformation that allows the presentation of a promiscuous repertoire of peptides similar to its functional homologue in mice, promoting a number of immunomodulatory effects as specific non-classical cytotoxic T cell responses rapidly responding to infections [13]. Accordingly, HLA-G+ cells control both the priming and the effector phases of the immune responses, therefore participating in peripheral immune tolerance, and these may be a target for strategies that have been aimed to develop immune checkpoint inhibitors (Figure 1) [12,14]. Thus, HLA-G+ immune cells are probably implicated in the complex mechanisms underlying the pathogenesis of various disorders including infections, transplants, cancers, and immune-mediated diseases [15,16,17,18].

2. Functions of HLA-G in Diseases

It has been reported that the expression of HLA-G polymorphic variants could be associated with susceptibility to different diseases [26,27]. Figure 2 shows some correlations between HLA-G expression and several disorders especially cancers [1,12,19,21,24,26,28,29,30,31,32,33,34,35,36,37]. Furthermore, the expression of HLA-G has been described in several infectious diseases caused by bacterial, viral, or parasitic agents (Table 1) [16,38,39]. In viral infections, the overexpression of HLA-G can lead to the induction of a tolerogenic environment and to the inhibition of the immune response which makes it an immune escape mechanism. Moreover, differential expression patterns of sHLA-G or its polymorphisms seem to be related to different pathological conditions, potentially acting as a disease progression biomarker and a therapeutic target [40]. To this end, a number of different monoclonal antibodies (mAbs) able to recognize several HLA-G isoforms (mainly HLA-G1 and HLA-G5) must be assayed for diagnostic purposes due to its cross-reactivity, mainly with the β2M free classical HLA class I antigens; in particular, the 4H84 mAb and because different epitopes of HLA-G are detected by different monoclonal antibodies. One mAb, the MEM-G/9 is the option to simultaneously detect by an enzyme-linked immunosorbent assay (ELISA) captured β2M-related HLA-G1 shedding and HLA-G5 using a polyclonal anti-β2M antiserum [41,42,43].
Overall, HLA-G expression is upregulated in infectious diseases in response to changes in the cytokine microenvironment that is mainly related to increased levels of IL-10 and class I interferons. sHLA-G can be also expressed as a membrane-bound form on monocytes or different types of T cells (mainly CD4 and regulatory T cells (Tregs)) [12]. HLA-G is expressed in infected tissues and more frequently in peripheral blood, in the form of sHLA-G via alternative splicing or proteolytic cleavage, with a half-life between 6 and 24 h. Interestingly, the metalloproteases involved in the cleavage of the HLA-G membrane-bound molecule may act also as anti-inflammatory molecules [44].
HLA-G may have deleterious effects, promoting pathogen escape from immune system control (in cancers), or it may be beneficial (in septic shock), reflecting appropriate and effective feedback control of inflammatory processes [45,46]. HLA-G can be a single marker of infectious diseases when dealing with pathogens and/or to the immune response, or it may constitute a therapeutic target, once its function has been clarified in particular types of infections [38].
Investigations into sHLA-G, including purified sHLA-G1 protein and sHLA-G-linked extracellular vesicles, revealed the potential role of sHLA-G in mediating immune-modulatory activities in different diseases towards differential modifications in the phenotype of CD8 T cells [20,47] and suggested it as a potential diagnostic and prognostic biomarker even being implicated in the predisposition to infection [11,48,49]. Both membrane-bound and sHLA-G induce regulatory mechanisms, such as apoptosis of CD8+ T and NK cells, inhibition of B-cell proliferation, differentiation, and antibody secretion [50,51]. For instance, the up-regulation of HLA-G in tumors and the enhanced serum levels of soluble form have been identified in malignancies, probably leading to tumoral immune evasion and cancer progression due to their inhibitory actions on the immune system [52].
Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) is currently a threat to human life worldwide. It is well known that different HLA alleles can affect antigen presentation and thus both the exposure and the severity of viral infections. Specifically, in SARS-CoV-2 infection, this correlation between HLAs and SARS-CoV-2 susceptibility and Coronavirus disease 2019 (COVID-19) severity has been highlighted, pointing out the relationship between particular alleles and severe infections [53]. Upregulated HLA molecules upon infections such as HLA-G membrane-bound, but mainly sHLA-G-, are potentially implicated in the suppression of immune system functions, including NK cells cytolysis, favoring immune tolerance to infections and thus virus subversion and replication during SARS-CoV-2 infections or COVID-19 disease [10,54]. Since the immune disability of NK cells has been related to interactions with its NKG2A/CD94 receptor that is upregulated in severe patients of COVID-19, the engagement of HLA-G to this receptor might be the cause of immune exhaustion observed in severe disease, which is highly dependent on key pathogen-induced cytokines and the binding affinity of different HLA-G alleles. In general, viral HLA-G upregulation can aggravate the morbidity of the virus and/or the mortality of the patient, such that HLA-G expression in these disorders may predict a worse outcome and increased susceptibility to cellular transformation [51].
The dynamics of peripheral immune cells, cytokines, and HLA-G and its receptor expressions have been described during critical COVID-19 pneumonia [55]. It has been suggested that the follow-up of sHLA-G could be used to identify the prognosis of COVID-19 among patients with high levels of sHLA-G [54,56]. It seems that HLA-G molecules control soluble Intercellular Adhesion Molecule-1 (sICAM-1) and sE-selectin expression through CD160 interaction and Fibroblast Growth Factor 2 (FGF2) induction and consequently lead to neutrophil adhesion and to the improvement of the disease outcomes [57]. The presence of HLA-G, as an important immune check point, might suggest the use of Immune-Checkpoint Inhibitors (ICIs) against this molecule in COVID-19 treatment [58].
HLA-G can interact with the inhibitory receptor Immunoglobulin-Like Transcript 2 (ILT2) in the blood and be secreted as a free soluble form (sHLA-G) or through extracellular vesicles [47]. Recently, new approaches revealed that the blockage of the HLA-G/ILT axis, could be insightful for the development of effective anti-tumor treatments strategies [59,60,61]. Since HLA-G exists in several polymorphs that affect both the protein expression levels and its peptide-binding cleft, targeting peptide binding cleft of the most common HLA-G polymorphs can also be suggested as a therapeutic strategy [31]. Moreover, it may be possible to modulate HLA-G transcription with microRNAs (miRNAs, miRs), such as hsa-miR-148a and miR-152, which bind to the 3′ untranslated region of the HLA-G gene (3’UTR), downregulating its mRNA levels [52,62]. Furthermore, mAs or RNA interfering strategies can be used to block HLA-G expression or HLA-G receptor, or the application of HLA-G-derived immunogenic peptide and anti-idiotype antibodies to activate immune cells can be fruitful approaches [15]. Since the option of blocking HLA-G using mAs appears unfeasible, mainly because they lack sufficient specificity, other options have recently been proposed. The core goal is directly blocking HLA-G binding with its receptors, and to this end, antibodies should be targeted for different key domains [14].
Therefore, based on the major immunomodulatory roles of HLA-G both in infectious and non-communicable diseases, we hypothesize a more-than-likely plausible capacity of key infections to upregulate HLA-G as therapeutic or immunomodulatory options, potentially allowing us to manage other infections.
Table 1. The correlation of HLA-G with infectious diseases caused by viruses, bacteria, and protozoan parasites.
Table 1. The correlation of HLA-G with infectious diseases caused by viruses, bacteria, and protozoan parasites.
Pathogens or
Diseases
HLA-GObservationsReferences
Hepatitis B virus (HBV)HLA-G (14 bp ins/ins genotype)Positive correlation with worse clinical manifestations[63]
sHLA-GA significant correlation with the phase of HBV infection, clinical diagnosis, and disease persistence, and also progression toward hepatocellular carcinoma[64]
Hepatitis C virus (HCV)Higher levels of sHLA-G and interleukin-10 (IL-10)Negative correlation with response to treatment[65]
HLA-GA plausible function in the genesis of HCV liver fibrosis[66]
Human immunodeficiency virus 1 (HIV-1)HLA-G polymorphismsHLA-G polymorphisms independently and synergistically induce susceptibility to heterosexual acquisition of HIV-1[67]
Human Papillomavirus (HPV)HLA-G polymorphismAssociations with the outcomes of oral HPV, affecting some characteristics of the women’s reproductive health, dual function (tumor progression and a good immunotherapeutic target) in cervical HPV[68,69]
Herpesvirus (6A and 6B)HLA-GInhibits in vitro angiogenesis through HLA-G[70]
Cytomegalovirus (CMV)HLA-GInfluences HLA-G expression in healthy individuals and probably contribute to viral immune evasion[71]
sHLA-GAs a promising biomarker of diagnosis of maternal CMV in maternal blood and amniotic fluid[72]
ArbovirussHLA-GA plausible biomarker to monitor neurological complications[73]
SARS-CoV-2HLA- GThe possible induction of profound immune suppression leading to the escape of virus from immune attack[10]
Helicobacter pyloriHLA-GCorrelated with milder colonization and milder inflammation[74]
Pseudomonas aeruginosasHLA-GDecreasing levels during antibiotic therapy in patients with cystic fibrosis (negative correlation with inflammation)[75]
HLA-GInducing HLA-G expression in monocytes and T cells by P. aeruginosa (protecting from immune responses)[76]
Tropheryma whippleiHLA-GIncreased HLA-G levels in patients’ sera (promoting bacteria colonization)[23]
Human African trypanosomiasis
(HAT)
HLA-G 3′ UTR-2 and UTR-5 haplotypesAssociation with increased susceptibility to HAT[77]
HLA-G 3′ UTR-4 haplotypeAssociation with a decreased risk of HAT
HLA-G 5′ URR-010102a/UTR-2 and 5′URR-
0103e/CR-G*01:03:01:02/UTR-5 haplotypes
Association with HAT disease progression[78]
HLA-G (rs1611139 T, rs17875389 A, rs9380142 G alleles)Association with increased risk of infection[79,80]
HLA-G (rs1233330 A, rs1233330 G alleles)Association with decreased risk of infection[80,81]
American trypanosomiasis
(Chagas disease)
Cell-surface HLA-GReduced HLA-G expression on cardiac muscle and colonic cells in patients with cardiac or digestive forms of Chagas, respectively[82]
HLA-G (+3003 T allele and +3003TT, +3187GG and +3196GC genotypes)Association with an enhanced risk of symptomatic Chagas
HLA-G (+3003C allele and +3003CT and +3196CC genotypes)Association with a decreased risk of symptomatic Chagas
HLA-G (+3027C and +3035C alleles and of +3027CC and +3035CC genotypes)Association with the digestive form of Chagas
MalariasHLA-GIncreased sHLA-G levels in cord blood and correlation with low weight at birth and clinical outcome (positive correlation with high risk of infection in infancy)[83]
HLA-G (+3187G allele and UTR1 haplotype)Association with reduced level of parasite burden during Plasmodium falciparum asymptomatic infection[84]
HLA-G (UTR3 haplotype)Association with enhanced level of parasite burden and increased severity of P. falciparum asymptomatic infection
HLA-G (+3010G and +3142C alleles)Association with enhanced total IgG and IgG1 antibodies levels against P. falciparum glutamate-rich protein (GLURP)[85]
HLA-G (+3196G and UTR2 haplotype)Association with a decreased IgG3 response against P. falciparum Merozoite Surface Protein 2 (MSP2)
sHLA-GThe correlation of increased sHLA-G levels in cord blood with low birth weight and an enhanced risk of malaria (P. falciparum) in the first year of life[83,86]
sHLA-GThe correlation of an increased mean sHLA-G levels during infancy with low birth weight and an enhanced risk of malaria (P. falciparum) during the two first years of life[87]
Visceral leishmaniasis (VL)sHLA-GIncreased levels of blood sHLA-G in Leishmania-infected patients[88]
Decreased levels of blood sHLA-G after anti-parasitic treatment of VL[89]
Toxoplasma spp.sHLA-GParasite increased the secretion of sHLA-G by trophoblast inducing apoptosis of decidual natural killer (dNK) cells (positive correlation with abnormal pregnancy)[90]
Increased sHLA-G levels in the amniotic fluid of pregnant women infected by Toxoplasma and in congenitally infected fetuses[91]
The increased secretion of sHLA-G by trophoblast due to Toxoplasma infection (inducing apoptosis of dNK cells)[90]
Cell-surface HLA-GIncreased HLA-G expression in the Toxoplasma-infected cells (decreasing HLA-G after treatment of infected cell by IL-10)[92]

3. HLA-G Expression in Parasitic Diseases

It has been shown that high levels of sHLA-G are correlated with its involvement in the immune tolerance induced by hookworm’s infections during pregnancy [93]. In echinococcosis, the cyst activity may induce the release of sHLA-G in the blood, highlighting the presence of an immune-modulatory strategy, leading to the downregulation of the host inflammatory responses [94]. Increased levels of sHLA-G have been reported in patients presenting active phase of echinococcosis [39].
The expression of HLA-G gene and molecule has been also investigated in protozoan parasitic diseases including African trypanosomiasis, Chagas disease, malaria, toxoplasmosis, and leishmaniasis [39]. For instance, the enhanced expression level of sHLA-G was correlated with the increased predisposition to develop human African trypanosomiasis and promoted susceptibility to malaria, suggesting sHLA-G as a prognostic biomarker in such diseases [39,78]. The level of sHLA-G is also a crucial biomarker of the incidence of malaria during infancy and further confirm that mother sHLA-G levels could be considered a diagnostic marker of malaria susceptibility in children [95]. Moreover, sHLA-G also exerts a critical immune-modulatory function to decrease fetal loss due to toxoplasmosis infection; however, its overexpression could lead to a congenital transmission [91].
Furthermore, co-infections by several parasites are not uncommon. For example, those by Schistosoma haematobium and Plasmodium falciparum are frequent [96,97,98,99]. It has been shown that children with S. haematobium and P. falciparum coinfections exhibit lower expression levels of LILRB2, one of the receptors of HLA-G in B cells and neutrophils. However, its interaction with HLA-G led to complex sHLA-G derived immune regulatory pathways inducing effective neutralizing antimalarial humoral responses. Moreover, the impact of malaria on viral co-infections has been highlighted in patients with both diseases, suggesting a potential of malaria parasites to improve COVID-19 management due to their immune derived ability to influence virus clearance and pathology [100].
In addition, antibody responses to protective vaccine candidates for malaria are dependent on polymorphisms in the HLA-G gene. sHLA-G upregulation upon vaccination has shown important regulatory effects on the response to vaccination, with a blood-stage malaria vaccine candidate stimulating antigen presenting cells to secrete this molecule. Such a molecule seems to have a dual regulatory role, modulating anti-vaccine responses generating a decreased immunogenicity upon vaccination. These observations suggest that, depending on the levels of sHLA-G, the vaccine immunogenicity and parasite infection progression may change [86,101,102].

4. HLA-G as Target for Potential Immunotherapeutic Strategy

Recent data have elucidated the plausible antagonism between parasites and parasites, parasites and bacteria, and parasites and viruses (including Plasmodium against Chikungunya virus, Heligmosomoides polygyrus against Respiratory Syncytial Virus, and Echinoparyphium against Ranavirus) through different mechanisms including immunomodulation, vector modulation, interference competition, and exploitation competition. The immunomodulation strategy could happen in co-infections by the reduction in immunopathological changes caused by the Th1-type immune response [103]. Although some viruses such as Herpesvirus B and SARS-CoV-2 stimulate the upregulation of HLA-G and HLA-E to facilitate immune escape [56,104], the induction (by different pathogens such as parasites) of a dramatic reduction in HLA-G expression levels in disorders or in pathogen-infected tissues might be significant.
In a recent study, it has been shown that there are common immune-dominant regions between SARS-CoV-2 and P. falciparum that may explain the low COVID-19 incidence in the malaria-endemic areas [105]. Interestingly, a decreased membrane-bound HLA-G has been detected in the placenta of patients infected by P. falciparum and in the heart and colon of Chagas disease patients [39]. Although the parasite may have a possible dual role regulating HLA-G, it seems that P. falciparum infection is able to downregulate HLA-G production (42% vs. 90% in controls) in extravillous cytotrophoblast cells in correlation with the increased presence of NK cells [106]. The increased number of NK cells is probably related to the direct or indirect action of some cytokines, especially the pro-inflammatory IL-10 produced by a large variety of cells such as macrophages, which also induce NK-cell proliferation [107]. Numerous pathogens, including malaria parasites, induce high levels of proinflammatory cytokines by the upregulation of co-inhibitory receptors [108]. These inhibitory receptors are present in unconventional T cells, pointing out the high potential of these cells in infectious diseases [109].
Both IL-10 and Transforming Growth Factor Beta (TGF-β) act as important anti-inflammatory immunomodulators helping to control malaria. Furthermore, at the early stages of SARS-CoV-2 infection, TGF-β upregulation and downstream signals have antiviral implications, as demonstrated with artemisin therapy. Moreover, there are data supporting the correlating levels of total sHLA-G in plasma with elevated TGF-β levels in systemic sclerosis, TGF-β also being one major factor upregulating HLA-G expression in cancers, and subsequently influencing immune cells mainly Treg cells and, on the other hand, participating in cancer immune escape and immune checkpoint resistance [110,111]. Thus, we speculate that the key immunomodulatory role of the cytokines TGF-β and IL-10 and the essential regulation of T cells including Treg cells by TGF-β might initially be linked molecularly at least during the early phase of parasite infections with HLA-G levels. This could be most probably through indirect regulatory interactions with the pathway (involving HLA-G) finally affecting different immune cells [112]. Publications with data of high levels of HLA-G, IL-10, and TGF-β bearing therapeutic exosomes improving disease symptoms together with peripheral blood cells unresponsiveness might support this molecular pathway [113]. In this sense, demonstrating the implication of HLA-G levels in TGF-β-derived signaling could serve as a novel and important therapeutic strategy [114,115]. From this angle, P. falciparum or special antigens related to this parasite might be involved in the HLA-G reduction in extravillous cytotrophoblast cells. Although the mechanisms leading to such conditions remain unknown, experimental studies in this regard could further highlight this issue and might suggest the use of parasites including P. falciparum in the modulation (reduction) of HLA-G expression in other tissues, such as tissues infected by SARS-CoV-2. Since impaired NK cell counts and the cytolytic activity of these cells are important characteristics of severe COVID-19 [116,117], the increased levels of NK cells induced by P. falciparum might be considered a potential mechanism and strategy related to immune-modulatory-based therapies against COVID-19.

5. Conclusions

Taking into account that, in parasite endemic areas of COVID-19 cases, the severity of the disease and numbers of deaths decreased mainly due to patient coinfections with parasites, it seems that the effect of some pathogens such as parasites restricting HLA-G expression can be further considered in future studies [118,119]. Unlike other viral or bacterial coinfections that negatively impact respiratory viral diseases such as COVID-19, some parasitic infections could modulate disease severity and the clinical outcome of other infectious diseases such as COVID-19 via intricate molecular networks involving HLA-G, IL-10/TGF-β, and Treg cells [103,118,120]. Finally, as master immune modulators, their levels may be critical for the development of proper immune responses to vaccination, thus serving as potential targeting molecules to achieve desirable outcomes. These data highlight the importance of HLA-G molecule immune modulation in the context of previous infections, revealing the promising outlook for future research on this molecule and its potential ability to understand pathogen interactions and the molecular mechanism underlying the specific criteria of suitable helminths for therapy and to manage COVID-19 disease progression and pathogenesis. This would be assessed adapting appropriate experimental model systems of coinfections which might also help to reinforce the idea of parasites more than their products, keeping proper immune function and the need of controlled exposures that may render us less susceptible to pandemics or chronic inflammatory diseases [121].

Author Contributions

Conceptualization: S.R. and R.M.-R.; writing—original draft preparation: S.R., C.V., R.T., R.M., M.A.-H. and A.M.; writing—review, editing and supervision: P.N. and R.M.-R. All authors have read and agreed to the published version of the manuscript.

Funding

This research was funded by the Spanish Ministry of Science and Innovation (PID2020-112713RB-C21), Fundación La Caixa (LCF/PR/PR13/51080005), Fundación Caja Navarra, Fundación Roviralta, Ubesol, the COST Actions CA18217 and CA18218, and EU Project unCoVer (Grant Agreement No 101016216).

Institutional Review Board Statement

Not applicable.

Informed Consent Statement

Not applicable.

Data Availability Statement

Not applicable.

Acknowledgments

We acknowledge the entities funding this job and the APC funding by the University of Salamanca.

Conflicts of Interest

The authors declare no conflict of interest.

References

  1. Wyatt, R.C.; Lanzoni, G.; Russell, M.A.; Gerling, I.; Richardson, S.J. What the HLA-I!-Classical and Non-classical HLA Class I and Their Potential Roles in Type 1 Diabetes. Curr. Diabetes Rep. 2019, 19, 159. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  2. Hauer, V.; Risti, M.; Miranda, B.L.; da Silva, J.S.; Cidral, A.L.; Pozzi, C.M.; de C Contieri, F.L.; Sadissou, I.A.; Donadi, E.A.; Augusto, D.G.; et al. The association of HLA-G polymorphisms and the synergistic effect of sMICA and sHLA-G with chronic kidney disease and allograft acceptance. PLoS ONE 2019, 14, e0212750. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  3. Arns, T.; Antunes, D.A.; Abella, J.R.; Rigo, M.M.; Kavraki, L.E.; Giuliatti, S.; Donadi, E.A. Structural Modeling and Molecular Dynamics of the Immune Checkpoint Molecule HLA-G. Front. Immunol. 2020, 11, 575076. [Google Scholar] [CrossRef] [PubMed]
  4. Robinson, J.; Barker, D.J.; Georgiou, X.; Cooper, M.A.; Flicek, P.; Marsh, S.G. Ipd-imgt/hla database. Nucleic Acids. Res. 2020, 48, D948–D955. [Google Scholar] [PubMed]
  5. Curigliano, G.; Criscitiello, C.; Gelao, L.; Goldhirsch, A. Molecular pathways: Human leukocyte antigen G (HLA-G). Clin. Cancer. Res. 2013, 19, 5564–5571. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  6. HoWangYin, K.-Y.; Loustau, M.; Wu, J.; Alegre, E.; Daouya, M.; Caumartin, J.; Sousa, S.; Horuzsko, A.; Carosella, E.D.; LeMaoult, J. Multimeric structures of HLA-G isoforms function through differential binding to LILRB receptors. Cell. Mol. Life Sci. 2012, 69, 4041–4049. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  7. Kuroki, K.; Matsubara, H.; Kanda, R.; Miyashita, N.; Shiroishi, M.; Fukunaga, Y.; Kamishikiryo, J.; Fukunaga, A.; Fukuhara, H.; Hirose, K.; et al. Structural and functional basis for LILRB immune checkpoint receptor recognition of HLA-G isoforms. J. Immunol. 2019, 203, 3386–3394. [Google Scholar] [CrossRef]
  8. Bu, X.; Zhong, J.; Li, W.; Cai, S.; Gao, Y.; Ping, B. Immunomodulating functions of human leukocyte antigen-G and its role in graft-versus-host disease after allogeneic hematopoietic stem cell transplantation. Ann. Hematol. 2021, 100, 1391–1400. [Google Scholar] [CrossRef]
  9. Zaborek-Łyczba, M.; Łyczba, J.; Mertowska, P.; Mertowski, S.; Hymos, A.; Podgajna, M.; Niedźwiedzka-Rystwej, P.; Grywalska, E. The HLA-G Immune Checkpoint Plays a Pivotal Role in the Regulation of Immune Response in Autoimmune Diseases. Int. J. Mol. Sci. 2021, 22, 13348. [Google Scholar] [CrossRef]
  10. Lin, A.; Yan, W.-H. Perspective of HLA-G Induced Immunosuppression in SARS-CoV-2 Infection. Front. Immunol. 2021, 12, 788769. [Google Scholar] [CrossRef]
  11. Zhang, Y.; Yu, S.; Han, Y.; Wang, Y.; Sun, Y. Human leukocyte antigen-G expression and polymorphisms promote cancer development and guide cancer diagnosis/treatment. Oncol. Lett. 2018, 15, 699–709. [Google Scholar] [CrossRef] [PubMed]
  12. Contini, P.; Murdaca, G.; Puppo, F.; Negrini, S. HLA-G Expressing Immune Cells in Immune Mediated Diseases. Front. Immunol. 2020, 11, 1613. [Google Scholar] [CrossRef] [PubMed]
  13. Anderson, C.K.; Brossay, L. The role of MHC class Ib-restricted T cells during infection. Immunogenetics 2016, 68, 677–691. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  14. Attia, J.V.; Dessens, C.E.; van de Water, R.; Houvast, R.D.; Kuppen, P.J.; Krijgsman, D. The Molecular and Functional Characteristics of HLA-G and the Interaction with Its Receptors: Where to Intervene for Cancer Immunotherapy? Int. J. Mol. Sci. 2020, 21, 8678. [Google Scholar] [CrossRef] [PubMed]
  15. Lin, A.; Yan, W.-H. Human leukocyte antigen-G (HLA-G) expression in cancers: Roles in immune evasion, metastasis and target for therapy. Mol. Med. 2015, 21, 782–791. [Google Scholar] [CrossRef] [PubMed]
  16. Morandi, F.; Rizzo, R.; Fainardi, E.; Rouas-Freiss, N.; Pistoia, V. Recent advances in our understanding of HLA-G biology: Lessons from a wide spectrum of human diseases. J. Immunol. Res. 2016, 2016, 4326495. [Google Scholar] [CrossRef] [Green Version]
  17. Da Silva, I.L.; Montero-Montero, L.; Ferreira, E.; Quintanilla, M. New insights into the role of Qa-2 and HLA-G non-classical MHC-I complexes in malignancy. Front. Immunol. 2018, 9, 2894. [Google Scholar] [CrossRef]
  18. Rizzo, R.; Bortolotti, D.; Bolzani, S.; Fainardi, E. HLA-G molecules in autoimmune diseases and infections. Front. Immunol. 2014, 5, 592. [Google Scholar] [CrossRef] [Green Version]
  19. Créput, C.; Durrbach, A.; Menier, C.; Guettier, C.; Samuel, D.; Dausset, J.; Charpentier, B.; Carosella, E.D.; Rouas-Freiss, N. Human leukocyte antigen-G (HLA-G) expression in biliary epithelial cells is associated with allograft acceptance in liver-kidney transplantation. J. Hepatol. 2003, 39, 587–594. [Google Scholar] [CrossRef]
  20. Amodio, G.; Gregori, S. The discovery of HLA-G-bearing extracellular vesicles: New perspectives in HLA-G biology. Ann. Transl. Med. 2017, 5, 148. [Google Scholar] [CrossRef] [Green Version]
  21. Wan, R.; Wang, Z.-W.; Li, H.; Peng, X.-D.; Liu, G.-Y.; Ou, J.-M.; Cheng, A.-Q. Human leukocyte antigen-G inhibits the an-ti-tumor effect of natural killer cells via immunoglobulin-like transcript 2 in gastric cancer. Cell. Physiol. Biochem. 2017, 44, 1828–1841. [Google Scholar] [CrossRef] [PubMed]
  22. Hölzemer, A.; Garcia-Beltran, W.F.; Altfeld, M. Natural killer cell interactions with classical and non-classical human leukocyte antigen class I in HIV-1 infection. Front. Immunol. 2017, 8, 1496. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  23. Azzouz, E.B.; Boumaza, A.; Mezouar, S.; Bardou, M.; Carlini, F.; Picard, C.; Raoult, D.; Mège, J.-L.; Desnues, B. Tropheryma whipplei increases expression of human Leukocyte Antigen-G on monocytes to reduce tumor necrosis factor and promote bacterial replication. Gastroenterology 2018, 155, 1553–1563. [Google Scholar] [CrossRef] [PubMed]
  24. Wastowski, I.J.; Simões, R.T.; Yaghi, L.; Donadi, E.A.; Pancoto, J.T.; Poras, I.; Lechapt-Zalcman, E.; Bernaudin, M.; Valable, S.; Carlotti, C.G., Jr.; et al. Human leukocyte antigen-G is frequently expressed in glioblastoma and may be induced in vitro by combined 5-aza-2′-deoxycytidine and interferon-γ treatments: Results from a multicentric study. Am. J. Pathol. 2013, 182, 540–552. [Google Scholar] [CrossRef] [PubMed]
  25. Li, C.; Toth, I.; Schulze zur Wiesch, J.; Pereyra, F.; Rychert, J.; Rosenberg, E.S.; van Lunzen, J.; Lichterfeld, M.; Yu, X.G. Func-tional characterization of HLA-G+ regulatory T cells in HIV-1 infection. PLoS Pathog. 2013, 9, e1003140. [Google Scholar] [CrossRef]
  26. Adolf, I.C.; Almars, A.; Dharsee, N.; Mselle, T.; Akan, G.; Nguma, I.J.; Nateri, A.S.; Atalar, F. HLA-G and single nucleotide polymorphism (SNP) associations with cancer in African populations: Implications in personal medicine. Genes Dis. 2021. [Google Scholar] [CrossRef]
  27. Arnaiz-Villena, A.; Juarez, I.; Suarez-Trujillo, F.; López-Nares, A.; Vaquero, C.; Palacio-Gruber, J.; Martin-Villa, J.M. HLA-G: Function, polymorphisms and pathology. Int. J. Immunogenet. 2021, 48, 172–192. [Google Scholar] [CrossRef]
  28. de Kruijf, E.M.; Sajet, A.; van Nes, J.G.; Natanov, R.; Putter, H.; Smit, V.T.; Liefers, G.J.; van den Elsen, P.J.; van de Velde, C.J.; Kuppen, P.J.K. HLA-E and HLA-G expression in classical HLA class I-negative tumors is of prognostic value for clinical outcome of early breast cancer patients. J. Immunol. 2010, 185, 7452–7459. [Google Scholar] [CrossRef] [Green Version]
  29. Nückel, H.; Rebmann, V.; Dürig, J.; Dührsen, U.; Grosse-Wilde, H. HLA-G expression is associated with an unfavorable out-come and immunodeficiency in chronic lymphocytic leukemia. Blood 2005, 105, 1694–1698. [Google Scholar]
  30. Li, X.; Sheng, Z.; Sun, Y.; Wang, Y.; Xu, M.; Zhang, Z.; Li, H.; Shao, L.; Zhang, Y.; Yu, J.; et al. Human leukocyte antigen-G upregulates immunoglobulin-like transcripts and corrects dysfunction of immune cells in immune thrombocytopenia. Haematologica 2021, 106, 770–781. [Google Scholar]
  31. Scarabel, L.; Garziera, M.; Fortuna, S.; Asaro, F.; Toffoli, G.; Geremia, S. Soluble HLA-G expression levels and HLA-G/irinotecan association in metastatic colorectal cancer treated with irinotecan-based strategy. Sci. Rep. 2020, 10, 8773. [Google Scholar] [CrossRef] [PubMed]
  32. Jucaud, V.; Ravindranath, M.; Terasaki, P. Immunobiology of HLA class-Ib molecules in transplantation. SOJ Immunol. 2015, 3, 1–15. [Google Scholar] [CrossRef]
  33. Avelino, M.A.G.; Wastowski, I.J.; Ferri, R.G.; Elias, T.G.A.; Lima, A.P.L.; Marinho, L.C.; Pignatari, S.S.N. The human leukocyte antigen G molecule (HLA-G) expression in patients with nasal polyposis. Braz. J. Otorhinolaryngol. 2014, 80, 208–212. [Google Scholar] [CrossRef] [PubMed]
  34. Abdul-Hussein, S.S.; Ali, E.N.; Zaki, N.H.; Ad’hiah, A.H. Genetic polymorphism of HLA-G gene (G*01:03, G*01:04, and G*01:05N) in Iraqi patients with inflammatory bowel disease (ulcerative colitis and Crohn’s disease). Eur. J. Hum. Genet. 2021, 22, 34. [Google Scholar] [CrossRef]
  35. Poomarimuthu, M.; Elango, S.; Soundrapandian, S.; Mariakuttikan, J. HLA-G 3′UTR gene polymorphisms and rheumatic heart disease: A familial study among South Indian population. Pediatr. Rheumatol. 2017, 15, 10. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  36. Rizzo, R.; Malagutti, N.; Bortolotti, D.; Gentili, V.; Rotola, A.; Fainardi, E.; Pezzolo, T.; Aimoni, C.; Pelucchi, S.; Di Luca, D.; et al. Infection and HLA-G molecules in nasal polyposis. J. Immunol. Res. 2014, 2014, 407430. [Google Scholar] [CrossRef] [PubMed]
  37. Barakat, G.; Elsharkawy, A.; Nabiel, Y. Human leucocyte antigen-G gene polymorphism in laryngeal squamous cell carcinoma patients in Mansoura University Hospitals. Egypt. J. Basic Appl. Sci. 2021, 8, 214–221. [Google Scholar] [CrossRef]
  38. Amiot, L.; Vu, N.; Samson, M. Immunomodulatory properties of HLA-G in infectious diseases. J. Immunol. Res. 2014, 2014, 298569. [Google Scholar] [CrossRef]
  39. Sabbagh, A.; Sonon, P.; Sadissou, I.; Mendes-Junior, C.; Garcia, A.; Donadi, E.; Courtin, D. The role of HLA-G in parasitic diseases. HLA 2018, 91, 255–270. [Google Scholar] [CrossRef]
  40. Donadi, E.A.; Castelli, E.C.; Arnaiz-Villena, A.; Roger, M.; Rey, D.; Moreau, P. Implications of the polymorphism of HLA-G on its function, regulation, evolution and disease association. Cell. Mol. Life Sci. 2011, 68, 369–395. [Google Scholar] [CrossRef] [Green Version]
  41. Poláková, K.; Kuba, D.; Russ, G. The 4H84 monoclonal antibody detecting β2m free nonclassical HLA-G molecules also binds to free heavy chains of classical HLA class I antigens present on activated lymphocytes. Hum. Immunol. 2004, 65, 157–162. [Google Scholar] [CrossRef] [PubMed]
  42. Swets, M.; König, M.H.; Zaalberg, A.; Dekker-Ensink, N.G.; Gelderblom, H.; van de Velde, C.J.; van den Elsen, P.J.; Kuppen, P.J. HLA-G and classical HLA class I expression in primary colorectal cancer and associated liver metastases. Hum. Immunol. 2016, 77, 773–779. [Google Scholar] [CrossRef] [PubMed]
  43. Rebmann, V.; LeMaoult, J.; Rouas-Freiss, N.; Carosella, E.; Grosse-Wilde, H. Quantification and identification of soluble HLA-G isoforms. Tissue Antigens 2007, 1, 143–149. [Google Scholar] [CrossRef] [PubMed]
  44. Rizzo, R.; Trentini, A.; Bortolotti, D.; Manfrinato, M.C.; Rotola, A.; Castellazzi, M.; Melchiorri, L.; Di Luca, D.; Dallocchio, F.; Fainardi, E. Matrix metalloproteinase-2 (MMP-2) generates soluble HLA-G1 by cell surface proteolytic shedding. Mol. Cell. Biochem. 2013, 381, 243–255. [Google Scholar] [CrossRef] [PubMed]
  45. Rodríguez, J.A. HLA-mediated tumor escape mechanisms that may impair immunotherapy clinical outcomes via T-cell acti-vation. Oncol. Lett. 2017, 14, 4415–4427. [Google Scholar] [CrossRef] [Green Version]
  46. Monneret, G.; Voirin, N.; Krawice-Radanne, I.; Bohé, J.; Lepape, A.; Rouas-Freiss, N.; Carosella, E.D. Soluble human leukocyte antigen-G5 in septic shock: Marked and persisting elevation as a predictor of survival. Crit. Care Med. 2007, 35, 1942–1947. [Google Scholar] [CrossRef]
  47. Schwich, E.; Hò, G.-G.T.; LeMaoult, J.; Bade-Döding, C.; Carosella, E.D.; Horn, P.A.; Rebmann, V. Soluble HLA-G and HLA-G bearing extracellular vesicles affect ILT-2 positive and ILT-2 negative CD8 T cells complementary. Front. Immunol. 2020, 11, 2046. [Google Scholar] [CrossRef]
  48. Bortolotti, D.; Gentili, V.; Rotola, A.; Potena, L.; Rizzo, R. Soluble HLA-G pre-transplant levels to identify the risk for devel-opment of infection in heart transplant recipients. Hum. Immunol. 2020, 81, 147–150. [Google Scholar] [CrossRef]
  49. Kluckova, K.; Durmanova, V.; Bucova, M. Soluble HLA-G, its diagnostic and prognostic value and potential target molecule for future therapy in cancer. Bratisl. Lek. Listy 2021, 122, 60–617. [Google Scholar] [CrossRef]
  50. Poras, I.; Yaghi, L.; Martelli-Palomino, G.; Mendes-Junior, C.T.; Muniz, Y.C.N.; Cagnin, N.F.; Sgorla de Almeida, B.; Castelli, E.C.; Carosella, E.D.; Donadi, E.A. Haplotypes of the HLA-G 3′ untranslated region respond to endogenous factors of HLA-G+ and HLA-G-cell lines differentially. PLoS ONE 2017, 12, e0169032. [Google Scholar]
  51. De Campos Fraga-Silva, T.F.; Maruyama, S.R.; Sorgi, C.A.; de Sousa Russo, E.M.; Fernandes, A.P.M.; de Barros Cardoso, C.R.; Faccioli, L.H.; Dias-Baruffi, M.; Bonato, V.L.D. COVID-19: Integrating the Complexity of Systemic and Pulmonary Immunopathology to Identify Biomarkers for Different Outcomes. Front. Immunol. 2021, 11, 599736. [Google Scholar] [CrossRef] [PubMed]
  52. Shahraki, P.K.; Alavian-Mehr, A.; Farjadian, S. HLA-G: Facts and Fictions. Asian Pac. J. Cancer Biol. 2018, 3, 37–45. [Google Scholar] [CrossRef] [Green Version]
  53. Nguyen, A.; David, J.K.; Maden, S.K.; Wood, M.A.; Weeder, B.R.; Nellore, A.; Thompson, R.F. Human leukocyte antigen susceptibility map for severe acute respiratory syndrome coronavirus 2. J. Virol. 2020, 94, e00510–e00520. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  54. Zidi, I. Puzzling out the COVID-19: Therapy targeting HLA-G and HLA-E. Hum. Immunol. 2020, 81, 697–701. [Google Scholar] [CrossRef] [PubMed]
  55. Zhang, S.; Gan, J.; Chen, B.-G.; Zheng, D.; Zhang, J.-G.; Lin, R.-H.; Zhou, Y.-P.; Yang, W.-Y.; Lin, A.; Yan, W.-H. Dynamics of peripheral immune cells and their HLA-G and receptor expressions in a patient suffering from critical COVID-19 pneumonia to convalescence. Clin. Transl. Immunol. 2020, 9, e1128. [Google Scholar] [CrossRef]
  56. Al-Bayatee, N.T.; Ad’hiah, A.H. Soluble HLA-G is upregulated in serum of patients with severe COVID-19. Hum. Immunol. 2021, 82, 726–732. [Google Scholar] [CrossRef] [PubMed]
  57. Bortolotti, D.; Gentili, V.; Rizzo, S.; Schiuma, G.; Beltrami, S.; Spadaro, S.; Strazzabosco, G.; Campo, G.; Carosella, E.D.; Papi, A. Increased sHLA-G Is Associated with Improved COVID-19 Outcome and Reduced Neutrophil Adhesion. Viruses 2021, 13, 1855. [Google Scholar] [CrossRef]
  58. Vivarelli, S.; Falzone, L.; Torino, F.; Scandurra, G.; Russo, G.; Bordonaro, R.; Pappalardo, F.; Spandidos, D.A.; Raciti, G.; Libra, M. Immune-checkpoint inhibitors from cancer to COVID-19: A promising avenue for the treatment of patients with COVID-19. Int. J. Oncol. 2021, 58, 145–157. [Google Scholar] [CrossRef] [PubMed]
  59. Xu, H.-H.; Gan, J.; Xu, D.-P.; Li, L.; Yan, W.-H. Comprehensive Transcriptomic Analysis Reveals the Role of the Immune Checkpoint HLA-G Molecule in Cancers. Front. Immunol. 2021, 12, 614773. [Google Scholar] [CrossRef] [PubMed]
  60. García, M.; Palma, M.B.; Verine, J.; Miriuka, S.; Inda, A.M.; Errecalde, A.L.; Desgrandchamps, F.; Carosella, E.D.; Tronik-Le Roux, D. The immune-checkpoint HLA-G/ILT4 is involved in the regulation of VEGF expression in clear cell renal cell carci-noma. BMC Cancer 2020, 20, 624. [Google Scholar] [CrossRef]
  61. Chen, Q.-Y.; Chen, Y.-X.; Han, Q.-Y.; Zhang, J.-G.; Zhou, W.-J.; Zhang, X.; Ye, Y.-H.; Yan, W.-H.; Lin, A. Prognostic Signifi-cance of Immune Checkpoints HLA-G/ILT-2/4 and PD-L1 in Colorectal Cancer. Front. Immunol. 2021, 12, 679090. [Google Scholar] [CrossRef] [PubMed]
  62. Manaster, I.; Goldman-Wohl, D.; Greenfield, C.; Nachmani, D.; Tsukerman, P.; Hamani, Y.; Yagel, S.; Mandelboim, O. MiRNA-mediated control of HLA-G expression and function. PLoS ONE 2012, 7, e33395. [Google Scholar] [CrossRef] [PubMed]
  63. Laaribi, A.; Zidi, I.; Hannachi, N.; Ben Yahia, H.; Chaouch, H.; Bortolotti, D.; Zidi, N.; Letaief, A.; Yacoub, S.; Boudabous, A. Association of an HLA-G 14-bp Insertion/Deletion polymorphism with high HBV replication in chronic hepatitis. J. Viral Hepat. 2015, 22, 835–841. [Google Scholar] [CrossRef] [PubMed]
  64. Rashidi, S.; Farhadi, L.; Ghasemi, F.; Sheikhesmaeili, F.; Mohammadi, A. The potential role of HLA-G in the pathogenesis of HBV infection: Immunosuppressive or immunoprotective? Infect. Genet. Evol. 2020, 85, 104580. [Google Scholar] [CrossRef]
  65. Khorrami, S.; Mohammadpour, H.; Shahzamani, K.; Zarif, M.N.; Sharifi, A.H.; Merat, S.; Poustchi, H. The relationship between HLA-G and viral loads in non-responder HCV-infected patients after combined therapy with IFN-α2α and ribavirin. Hum. Immunol. 2015, 76, 181–186. [Google Scholar] [CrossRef]
  66. Amiot, L.; Vu, N.; Rauch, M.; L’Helgoualc’h, A.; Chalmel, F.; Gascan, H.; Turlin, B.; Guyader, D.; Samson, M. Expression of HLA-G by mast cells is associated with hepatitis C virus-induced liver fibrosis. J. Hepatol. 2014, 60, 245–252. [Google Scholar] [CrossRef] [Green Version]
  67. Lajoie, J.; Hargrove, J.; Zijenah, L.S.; Humphrey, J.H.; Ward, B.J.; Roger, M. Genetic variants in nonclassical major histo-compatibility complex class I human leukocyte antigen (HLA)-E and HLA-G molecules are associated with susceptibility to heterosexual acquisition of HIV-1. J. Infect. Dis. 2006, 193, 298–301. [Google Scholar] [CrossRef] [Green Version]
  68. Jaakola, A.; Roger, M.; Faucher, M.-C.; Syrjänen, K.; Grénman, S.; Syrjänen, S.; Louvanto, K. HLA-G polymorphism impacts the outcome of oral HPV infections in women. BMC Infect. Dis. 2021, 21, 419. [Google Scholar] [CrossRef]
  69. Xu, H.-H.; Yan, W.-H.; Lin, A. The Role of HLA-G in Human Papillomavirus Infections and Cervical Carcinogenesis. Front. Immunol. 2020, 11, 1349. [Google Scholar] [CrossRef]
  70. Rizzo, R.; D’Accolti, M.; Bortolotti, D.; Caccuri, F.; Caruso, A.; Di Luca, D.; Caselli, E. Human Herpesvirus 6A and 6B inhibit in vitro angiogenesis by induction of Human Leukocyte Antigen G. Sci. Rep. 2018, 8, 17683. [Google Scholar] [CrossRef]
  71. Albayati, Z.; Alyami, A.; Alomar, S.; Middleton, D.; Bonnett, L.; Aleem, S.; Flanagan, B.F.; Christmas, S.E. The Influence of Cytomegalovirus on Expression of HLA-G and its Ligand KIR 2 DL 4 by Human Peripheral Blood Leucocyte Subsets. Scand. J. Immunol. 2017, 86, 396–407. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  72. Rizzo, R.; Gabrielli, L.; Bortolotti, D.; Gentili, V.; Piccirilli, G.; Chiereghin, A.; Pavia, C.; Bolzani, S.; Guerra, B.; Simonazzi, G. Study of soluble HLA-G in congenital human cytomegalovirus infection. J. Immunol. Res. 2016, 2016, 3890306. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  73. Almeida, R.S.; Ferreira, M.L.B.; Sonon, P.; Cordeiro, M.T.; Sadissou, I.; Diniz, G.T.N.; de Fatima Pessoa Militão-Albuquerque, M.; Franca, R.F.D.O.; Donadi, E.A.; Lucena-Silva, N. Cytokines and soluble HLA-G levels in the acute and recovery phases of arbo-virus-infected Brazilian patients exhibiting neurological complications. Front. Immunol. 2021, 12, 582935. [Google Scholar] [CrossRef] [PubMed]
  74. Oliveira Souza, D.M.B.; Genre, J.; Alves Silva, T.G.; Soares, C.P.; Borges Ferreira Rocha, K.; Nunes Oliveira, C.; Nunes Jatoba, C.A.; Marco de Leon Andrade, J.; Moreau, P.; da Cunha Medeiros, A.; et al. Upregulation of Soluble HLA-G5 and HLA-G6 Isoforms in the Milder Histopathological Stages of Helicobacter pylori Infection: A Role for Subverting Immune Responses? Scand. J. Immunol. 2016, 83, 38–43. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  75. Rizzo, R.; Bergamini, G.; Bortolotti, D.; Leal, T.; D’Orazio, C.; Pintani, E.; Melchiorri, L.; Zavatti, E.; Assael, B.M.; Sorio, C. HLA-G expression and regulation during Pseudomonas aeruginosa infection in cystic fibrosis patients. Future Microbiol. 2016, 11, 363–373. [Google Scholar] [CrossRef] [Green Version]
  76. Bortolotti, D.; LeMaoult, J.; Trapella, C.; Di Luca, D.; Carosella, E.D.; Rizzo, R. Pseudomonas aeruginosa quorum sensing molecule N-(3-oxododecanoyl)-L-homoserine-lactone induces HLA-G expression in human immune cells. Infect. Immun. 2015, 83, 3918–3925. [Google Scholar] [CrossRef] [Green Version]
  77. Courtin, D.; Milet, J.; Sabbagh, A.; Massaro, J.D.; Castelli, E.C.; Jamonneau, V.; Bucheton, B.; Sese, C.; Favier, B.; Rouas-Freiss, N. HLA-G 3′ UTR-2 haplotype is associated with Human African trypanosomiasis susceptibility. Infect. Genet. Evol. 2013, 17, 1–7. [Google Scholar] [CrossRef]
  78. Gineau, L.; Courtin, D.; Camara, M.; Ilboudo, H.; Jamonneau, V.; Dias, F.C.; Tokplonou, L.; Milet, J.; Mendonça, P.B.; Castelli, E.C.; et al. Human leukocyte antigen-G: A promising prognostic marker of disease progression to improve the control of human Af-rican trypanosomiasis. Clin. Infect. Dis. 2016, 63, 1189–1197. [Google Scholar] [CrossRef]
  79. Ahouty, B.; Koffi, M.; Ilboudo, H.; Simo, G.; Matovu, E.; Mulindwa, J.; Hertz-Fowler, C.; Bucheton, B.; Sidibé, I.; Jamonneau, V.; et al. Candidate genes-based investigation of susceptibility to Human African Trypanosomiasis in Côte d’Ivoire. PLoS Negl. Trop. Dis. 2017, 11, e0005992. [Google Scholar] [CrossRef] [Green Version]
  80. Ofon, E.; Noyes, H.; Mulindwa, J.; Ilboudo, H.; Simuunza, M.; Ebo’o, V.; Njiokou, F.; Koffi, M.; Bucheton, B.; Fogue, P.; et al. A polymorphism in the haptoglobin, haptoglobin related protein locus is associated with risk of human sleeping sickness within Cameroonian populations. PLoS Negl. Trop. Dis. 2017, 11, e0005979. [Google Scholar] [CrossRef] [Green Version]
  81. Kimuda, M.P.; Noyes, H.; Mulindwa, J.; Enyaru, J.; Alibu, V.P.; Sidibe, I.; Mumba Ngoyi, D.; Hertz-Fowler, C.; MacLeod, A.; Tastan Bishop, Ö.; et al. No evidence for association between APOL1 kidney disease risk alleles and Human African Trypanosomiasis in two Ugandan populations. PLoS Negl. Trop. Dis. 2018, 12, e0006300. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  82. Dias, F.C.; Mendes-Junior, C.T.; Silva, M.C.; Tristão, F.S.; Dellalibera-Joviliano, R.; Moreau, P.; Soares, E.G.; Menezes, J.G.; Schmidt, A.; Dantas, R.O.; et al. Human leucocyte antigen-G (HLA-G) and its murine functional homolog Qa2 in the Trypanosoma cruzi Infection. Mediat. Inflamm. 2015, 2015, 595829. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  83. Sadissou, I.; d’Almeida, T.; Cottrell, G.; Luty, A.; Krawice-Radanne, I.; Massougbodji, A.; Moreau, P.; Moutairou, K.; Garcia, A.; Favier, B.; et al. High plasma levels of HLA-G are associated with low birth weight and with an increased risk of malaria in infancy. Malar. J. 2014, 13, 312. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  84. Garcia, A.; Milet, J.; Courtin, D.; Sabbagh, A.; Massaro, J.D.; Castelli, E.C.; Migot-Nabias, F.; Favier, B.; Rouas-Freiss, N.; Donadi, E.A.; et al. Association of HLA-G 3′ UTR polymorphisms with response to malaria infection: A first insight. Infect. Genet. Evol. 2013, 16, 263–269. [Google Scholar] [CrossRef]
  85. Sabbagh, A.; Courtin, D.; Milet, J.; Massaro, J.D.; Castelli, E.C.; Migot-Nabias, F.; Favier, B.; Rouas-Freiss, N.; Moreau, P.; Garcia, A.; et al. Association of HLA-G 3′ untranslated region polymorphisms with antibody response against Plasmodium falciparum antigens: Preliminary results. Tissue Antigens 2013, 82, 53–58. [Google Scholar] [CrossRef]
  86. D’Almeida, T.C.; Sadissou, I.; Cottrell, G.; Tahar, R.; Moreau, P.; Favier, B.; Moutairou, K.; Donadi, E.A.; Massougbodji, A.; Rouass-Freiss, N. Evolution of the levels of human leukocyte antigen G (HLA-G) in Beninese infant during the first year of life in a malaria endemic area: Using latent class analysis. Malar. J. 2016, 15, 78. [Google Scholar] [CrossRef] [Green Version]
  87. d’Almeida, T.C.; Sadissou, I.; Milet, J.; Cottrell, G.; Mondière, A.; Avokpaho, E.; Gineau, L.; Sabbagh, A.; Massougbodji, A.; Moutairou, K.; et al. Soluble human leukocyte antigen-G during pregnancy and infancy in Benin: Mother/child resemblance and association with the risk of malaria infection and low birth weight. PLoS ONE 2017, 12, e0171117. [Google Scholar] [CrossRef]
  88. Donaghy, L.; Gros, F.; Amiot, L.; Mary, C.; Maillard, A.; Guiguen, C.; Gangneux, J.-P. Elevated levels of soluble non-classical major histocompatibility class I molecule human leucocyte antigen (HLA)-G in the blood of HIV-infected patients with or without visceral leishmaniasis. Clin. Exp. Immunol. 2007, 147, 236–240. [Google Scholar] [CrossRef]
  89. Gangneux, J.-P.; Poinsignon, Y.; Donaghy, L.; Amiot, L.; Tarte, K.; Mary, C.; Robert-Gangneux, F. Indoleamine 2,3-dioxygenase activity as a potential biomarker of immune suppression during visceral leishmaniasis. Innate Immun. 2013, 19, 564–568. [Google Scholar] [CrossRef]
  90. Han, M.; Jiang, Y.; Lao, K.; Xu, X.; Zhan, S.; Wang, Y.; Hu, X. sHLA-G involved in the apoptosis of decidual natural killer cells following Toxoplasma gondii infection. Inflammation 2014, 37, 1718–1727. [Google Scholar] [CrossRef]
  91. Robert-Gangneux, F.; Gangneux, J.-P.; Vu, N.; Jaillard, S.; Guiguen, C.; Amiot, L. High level of soluble HLA-G in amniotic fluid is correlated with congenital transmission of Toxoplasma gondii. Clin. Immunol. 2011, 138, 129–134. [Google Scholar] [CrossRef] [PubMed]
  92. Zhao, M.; Zhang, R.; Xu, X.; Liu, Y.; Zhang, H.; Zhai, X.; Hu, X. IL-10 reduces levels of apoptosis in Toxoplasma gondii-infected trophoblasts. PLoS ONE 2013, 8, e56455. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  93. Avokpaho, E.; d’Almeida, T.C.; Sadissou, I.; Tokplonou, L.; Adamou, R.; Sonon, P.; Milet, J.; Cottrell, G.; Mondière, A.; Mas-sougbodji, A. HLA-G expression during hookworm infection in pregnant women. Acta Trop. 2019, 196, 52–59. [Google Scholar] [CrossRef]
  94. Mariconti, M.; Meroni, V.; Badulli, C.; Brunetti, E.; Tinelli, C.; De Silvestri, A.; Tamarozzi, F.; Genco, F.; Casulli, A.; Martinetti, M. Correlation of serum sHLA-G levels with cyst stage in patients with cystic echinococcosis: Is it an immune evasion strategy? Parasite Immunol. 2016, 38, 414–418. [Google Scholar] [CrossRef] [PubMed]
  95. d’Almeida, T.C.; Sadissou, I.; Sagbohan, M.; Milet, J.; Avokpaho, E.; Gineau, L.; Sabbagh, A.; Moutairou, K.; Donadi, E.A.; Favier, B.; et al. High level of soluble human leukocyte antigen (HLA)-G at beginning of pregnancy as predictor of risk of malaria during infancy. Sci. Rep. 2019, 9, 9160. [Google Scholar] [CrossRef] [PubMed]
  96. Wilairatana, P.; Masangkay, F.R.; Kotepui, K.U.; Milanez, G.D.J.; Kotepui, M. Prevalence and characteristics of malaria among COVID-19 individuals: A systematic review, meta-analysis, and analysis of case reports. PLoS Negl. Trop. Dis. 2021, 15, e0009766. [Google Scholar] [CrossRef]
  97. Wilairatana, P.; Chanmol, W.; Rattaprasert, P.; Masangkay, F.R.; Milanez, G.D.J.; Kotepui, K.U.; Kotepui, M. Prevalence and characteristics of malaria co-infection among individuals with visceral leishmaniasis in Africa and Asia: A systematic review and meta-analysis. Parasites Vectors 2021, 14, 545. [Google Scholar] [CrossRef]
  98. Anchang-Kimbi, J.K.; Elad, D.M.; Sotoing, G.T.; Achidi, E.A. Coinfection with Schistosoma haematobium and Plasmodium falci-parum and anaemia severity among pregnant women in Munyenge, Mount Cameroon area: A cross-sectional study. J. Parasitol. Res. 2017, 2017, 6173465. [Google Scholar] [CrossRef] [Green Version]
  99. Lemaitre, M.; Watier, L.; Briand, V.; Garcia, A.; Le Hesran, J.-Y.; Cot, M. Coinfection with Plasmodium falciparum and Schistosoma haematobium: Additional evidence of the protective effect of Schistosomiasis on malaria in Senegalese children. Am. J. Trop. Med. Hyg. 2014, 90, 329–334. [Google Scholar] [CrossRef] [Green Version]
  100. Zawawi, A.; Alghanmi, M.; Alsaady, I.; Gattan, H.; Zakai, H.; Couper, K. The impact of COVID-19 pandemic on malaria elimination. Parasite Epidemiol. Control 2020, 11, e00187. [Google Scholar] [CrossRef]
  101. Tokplonou, L.; Nouatin, O.; Sonon, P.; M’po, G.; Glitho, S.; Agniwo, P.; Gonzalez-Ortiz, D.; Tchégninougbo, T.; Ayitchédji, A.; Favier, B.; et al. Schistosoma haematobium infection modulates Plasmodium falciparum parasite density and antimalarial antibody re-sponses. Parasite Immunol. 2020, 42, e12702. [Google Scholar] [CrossRef] [PubMed]
  102. Nouatin, O.; Ngoa, U.A.; Ibáñez, J.; Dejon-Agobe, J.C.; Mordmüller, B.; Edoa, J.R.; Mougeni, F.; Brückner, S.; Hounkpatin, A.B.; Esen, M.; et al. Effect of immune regulatory pathways after immunization with GMZ2 malaria vaccine candidate in healthy lifelong malaria-exposed adults. Vaccine 2020, 38, 4263–4272. [Google Scholar] [CrossRef] [PubMed]
  103. Shen, S.-S.; Qu, X.-Y.; Zhang, W.-Z.; Li, J.; Lv, Z.-Y. Infection against infection: Parasite antagonism against parasites, viruses and bacteria. Infect. Dis. Poverty 2019, 8, 49. [Google Scholar] [CrossRef] [PubMed]
  104. Vasireddi, M.; Hilliard, J. Herpes B virus, macacine herpesvirus 1, breaks simplex virus tradition via major histocompatibility complex class I expression in cells from human and macaque hosts. J. Virol. 2012, 86, 12503–12511. [Google Scholar] [CrossRef] [Green Version]
  105. Iesa, M.A.; Osman, M.E.; Hassan, M.A.; Dirar, A.I.; Abuzeid, N.; Mancuso, J.J.; Pandey, R.; Mohammed, A.A.; Borad, M.J.; Babiker, H.M.; et al. SARS-CoV-2 and Plasmodium falciparum common immunodominant regions may explain low COVID-19 incidence in the malaria-endemic belt. New Microbes New Infect. 2020, 38, 100817. [Google Scholar] [CrossRef]
  106. Sartelet, H.; Schleiermacher, D.; Le-Hesran, J.-Y.; Graesslin, O.; Gaillard, D.; Fe, M.; Lechki, C.; Gaye, A.; Le Bouteiller, P.; Birembaut, P. Less HLA-G expression in Plasmodium falciparum-infected third trimester placentas is associated with more natural killer cells. Placenta 2005, 26, 505–511. [Google Scholar] [CrossRef]
  107. Sancho, L.; Martinez, C.; Nogales, A.; De La Hera, A. Reconstitution of natural-killer-cell activity in the newborn by interleu-kin-2. N. Engl. J. Med. 1986, 314, 57–58. [Google Scholar]
  108. Herrmann, M.; Schulte, S.; Wildner, N.H.; Wittner, M.; Brehm, T.T.; Ramharter, M.; Woost, R.; Lohse, A.W.; Jacobs, T.; Schulze zur Wiesch, J. Analysis of co-inhibitory receptor expression in COVID-19 infection compared to acute Plasmodium falciparum malaria: LAG-3 and TIM-3 correlate with t cell activation and course of disease. Front. Immunol. 2020, 11, 1870. [Google Scholar] [CrossRef]
  109. La Manna, M.P.; Orlando, V.; Tamburini, B.; Badami, G.D.; Dieli, F.; Caccamo, N. Harnessing unconventional T cells for immunotherapy of tuberculosis. Front. Immunol. 2020, 11, 2107. [Google Scholar] [CrossRef]
  110. Bai, X.; Yi, M.; Jiao, Y.; Chu, Q.; Wu, K. Blocking TGF-β signaling to enhance the efficacy of immune checkpoint inhibitor. OncoTargets Ther. 2019, 12, 9527. [Google Scholar] [CrossRef] [Green Version]
  111. Ullah, M.; Azazzen, D.; Kaci, R.; Benabbou, N.; Lauraine, E.P.; Pocard, M.; Mirshahi, M. High expression of HLA-G in ovarian carcinomatosis: The role of interleukin-1β. Neoplasia 2019, 21, 331–342. [Google Scholar] [CrossRef] [PubMed]
  112. Mirzaei, H.; Faghihloo, E. Viruses as key modulators of the TGF-β pathway; a double-edged sword involved in cancer. Rev. Med. Virol. 2018, 28, e1967. [Google Scholar] [CrossRef] [PubMed]
  113. Kordelas, L.; Rebmann, V.; Ludwig, A.; Radtke, S.; Ruesing, J.; Doeppner, T.; Epple, M.; Horn, P.; Beelen, D.; Giebel, B. MSC-derived exosomes: A novel tool to treat therapy-refractory graft-versus-host disease. Leukemia 2014, 28, 970–973. [Google Scholar] [CrossRef]
  114. Uckun, F.M.; Saund, S.; Windlass, H.; Trieu, V. Repurposing Anti-Malaria Phytomedicine Artemisinin as a COVID-19 Drug. Front. Pharmacol. 2021, 12, 407. [Google Scholar] [CrossRef]
  115. Drewry, L.L.; Harty, J.T. Balancing in a black box: Potential immunomodulatory roles for TGF-β signaling during blood-stage malaria. Virulence 2020, 11, 159–169. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  116. Osman, M.; Faridi, R.M.; Sligl, W.; Shabani-Rad, M.-T.; Dharmani-Khan, P.; Parker, A.; Kalra, A.; Tripathi, M.B.; Storek, J.; Cohen Tervaert, J.W.; et al. Impaired natural killer cell counts and cytolytic activity in patients with severe COVID-19. Blood Adv. 2020, 4, 5035–5039. [Google Scholar] [CrossRef]
  117. Ahmed, F.; Jo, D.-H.; Lee, S.-H. Can Natural Killer Cells Be a Principal Player in Anti-SARS-CoV-2 Immunity? Front. Immunol. 2020, 11, 586765. [Google Scholar] [CrossRef]
  118. Ademe, M.; Girma, F. The Influence of Helminth Immune Regulation on COVID-19 Clinical Outcomes: Is it Beneficial or Det-rimental? Infect. Drug Resist. 2021, 14, 4421. [Google Scholar] [CrossRef]
  119. Wolday, D.; Gebrecherkos, T.; Arefaine, Z.G.; Kebede, Y.; Gebreegzabher, A.; Tasew, G.; Abdulkader, M.; Abraha, H.E.; Desta, A.A.; Atsbaha, A.H.; et al. Effect of Co-Infection with Intestinal Parasites on COVID-19 Severity: A Prospective Observational Cohort Study. eClinicalMedicine 2021, 39, 101054. [Google Scholar] [CrossRef]
  120. Hoque, M.N.; Akter, S.; Mishu, I.D.; Islam, M.R.; Rahman, M.S.; Akhter, M.; Islam, I.; Hasan, M.M.; Rahaman, M.M.; Sultana, M.; et al. Microbial co-infections in COVID-19: Associated microbiota and underlying mechanisms of pathogenesis. Microb. Pathog. 2021, 156, 104941. [Google Scholar] [CrossRef]
  121. Parker, W.; Sarafian, J.T.; Broverman, S.A.; Laman, J.D. Between a hygiene rock and a hygienic hard place: Avoiding SARS-CoV-2 while needing environmental exposures for immunity. Evol. Med. Public Health 2021, 9, 120–130. [Google Scholar] [CrossRef] [PubMed]
Figure 1. Various immune tolerogenic properties of HLA-G by modulating the functions of immune cells [15,19,20,21,22,23,24,25].
Figure 1. Various immune tolerogenic properties of HLA-G by modulating the functions of immune cells [15,19,20,21,22,23,24,25].
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Figure 2. Correlation between HLA-G expression and different disorders.
Figure 2. Correlation between HLA-G expression and different disorders.
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Rashidi, S.; Vieira, C.; Tuteja, R.; Mansouri, R.; Ali-Hassanzadeh, M.; Muro, A.; Nguewa, P.; Manzano-Román, R. Immunomodulatory Potential of Non-Classical HLA-G in Infections including COVID-19 and Parasitic Diseases. Biomolecules 2022, 12, 257. https://doi.org/10.3390/biom12020257

AMA Style

Rashidi S, Vieira C, Tuteja R, Mansouri R, Ali-Hassanzadeh M, Muro A, Nguewa P, Manzano-Román R. Immunomodulatory Potential of Non-Classical HLA-G in Infections including COVID-19 and Parasitic Diseases. Biomolecules. 2022; 12(2):257. https://doi.org/10.3390/biom12020257

Chicago/Turabian Style

Rashidi, Sajad, Carmen Vieira, Renu Tuteja, Reza Mansouri, Mohammad Ali-Hassanzadeh, Antonio Muro, Paul Nguewa, and Raúl Manzano-Román. 2022. "Immunomodulatory Potential of Non-Classical HLA-G in Infections including COVID-19 and Parasitic Diseases" Biomolecules 12, no. 2: 257. https://doi.org/10.3390/biom12020257

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