Search Results (3,359)

CARINH is an intriguing long noncoding RNA whose unique regulatory functions intersect the seemingly distinct processes of innate immunity and cancer development. Notably, CARINH is conserved across species, offering powerful experimental models for uncovering its mechanistic roles and physiological functions across diverse biological contexts. Stimulated by interferons and viral infections, CARINH stands out as a key player in the body’s antiviral defense mechanisms. Additionally, its dysregulation has been implicated in autoimmune disorders such as psoriasis, asthma, and inflammatory bowel disease, underscoring its broader role in maintaining immune homeostasis. Furthermore, alterations in CARINH expression have been connected to cancer progression, highlighting its dual role in immune response and tumor suppression. In this review, we delve into CARINH’s pivotal function in modulating interferon responses and influencing cancer development, with a focus on the molecular pathways that regulate its expression and contribute to its diverse roles. Understanding these pathways is crucial for evaluating CARINH’s significance as a biomarker and therapeutic target, potentially leading to groundbreaking advancements in medical research and treatment strategies. Full article

Background/Objectives: Despite extensive research on hepatitis B virus (HBV), its post-transcriptional regulatory mechanisms remain incompletely characterized, particularly regarding epitranscriptomic modifications. This study aims to systematically profile the transcriptomic complexity and RNA modification landscape of HBV in hepatocellular carcinoma models. Methods: We transfected PLC/PRF/5 and Huh7 cells with the HBV 1.3-mer WT replicon plasmid, followed by qPCR measurement of viral load. Total nucleic acids extracted from transfected cells underwent nanopore direct RNA sequencing. The complete HBV transcriptome was then analyzed in two established hepatocellular carcinoma cell lines (PLC/PRF/5 and Huh7), with alternative splicing, polyadenylation, and RNA modifications identified through comprehensive bioinformatics analysis. Results: Our analysis revealed substantial transcriptomic diversity, identifying 34 distinct splice variants—including 14 previously unreported isoforms—with cell-type-specific expression patterns. Additionally, we detected 30 high-confidence RNA modification sites across HBV transcripts, with 93% (28 sites) conserved between both cellular environments. Notably, we observed significant intercellular heterogeneity in poly(A) tail length distributions. Conclusions: A comparison of the post-transcriptional processing modifications of HBV in PLC/PRF/5 and Huh7 cells reveals that the former may be better able to mimic the immune evasion mechanisms of chronic HBV infection. In contrast, the longer poly(A) tails present in Huh7 cells facilitate efficient replication, rendering these cells more amenable to the study of HBV transcription and replication mechanisms. These findings comprehensively elucidate the post-transcriptional regulatory mechanisms of hepatitis B virus in different hepatocellular carcinoma cell lines, establishing a critical benchmark for selecting appropriate experimental models in virology research. The identified transcriptomic features may provide new insights for developing antiviral strategies targeting the viral epigenome. Full article

Mpox, a zoonotic viral disease, has emerged as a global concern due to outbreaks in both endemic and non-endemic regions in 2022. Rodents, including African squirrels and Gambian pouched rats, are suspected key reservoirs, with human infections occurring through direct contact with infected animals or bushmeat consumption. Previously confined to rural Africa, mpox has spread via international travel and the exotic pet trade. Human-to-human transmission occurs mainly via respiratory droplets and direct contact with bodily fluids or lesions. The virus has a double-stranded DNA genome within a lipid envelope. Despite lower mutation rates in DNA viruses, mpox has developed mutations, particularly in genes like F8L, G9R, and F13L, facilitating viral replication and immune evasion. The virus targets immune cells such as monocytes and macrophages, weakening host defenses and prolonging infection. Immunocompromised individuals are at higher risk of severe complications. Although generally self-limiting, severe cases may require antiviral treatment. This article briefly summarizes the therapeutic and preventive strategies, and public health measures to combat zoonotic threats. Full article

Agriculture is still at serious risk from viral infections, particularly in light of climate change and more intensive farming practices. Small non-coding RNAs (sRNAs), in particular microRNAs (miRNAs) and circular RNAs (circRNAs), have emerged as crucial post-transcriptional regulators of plant antiviral defense in this setting. These molecules provide an essential RNA-based immunity layer by regulating hormones, autophagy, redox balance, immunological signaling, and programmed cell death. In this work, we examine the molecular processes through which circRNAs and miRNAs function during viral infection, focusing on how they affect autophagy and systemic acquired resistance (SAR). Through thorough searches of PubMed, Web of Science, and Scopus, we combined findings from peer-reviewed experimental and transcriptomic studies. Our study covers important crops as well as model species (Arabidopsis thaliana, Nicotiana benthamiana), providing a thorough understanding of sRNA synthesis, target control, and antiviral signaling. By combining previously disparate data, this review provides a coherent framework for understanding how short RNAs affect plant immune responses to viral infections. We highlight key regulatory relationships that need further study and propose that these results can be used as a foundation for new RNA-based biotechnological approaches. By carefully altering RNA regulatory mechanisms, scientists can use this information to help them create more resistant crops. Full article

The continuous emergence of SARS-CoV-2 variants with enhanced transmissibility and immune escape capability underscores the urgent need for mutation-independent anti-viral strategies. SARS-CoV-2 non-structural protein 12 (NSP12), which encodes the RNA-dependent RNA polymerase (RdRp), is an essential component of the viral replication complex and represents a highly conserved target for therapeutic intervention. In this study, we developed RNA aptamers, composed of 2′-hydroxyl nucleotides or 2′-fluoro pyrimidines, targeting NSP12 using the SELEX (Systematic Evolution of Ligands by EXponential enrichment) approach. SELEX was performed with purified NSP12 protein derived from the Omicron variant, leading to the identification of aptamer candidates with high binding ability. RNA–protein pull-down assays confirmed binding between representative aptamers and NSP12 with high affinity. Competition assays supported binding specificity between aptamers and NSP12. Of note, functional evaluation using a primer extension assay revealed that the aptamers effectively inhibited NSP12 RdRp activity in vitro. Furthermore, the aptamers consistently bound to and inhibited NSP12 variants from wild-type, Alpha, Delta, and Omicron strains. These results suggest that the selected RNA aptamers are potential as broad-spectrum inhibitors targeting a conserved region of NSP12 and may serve as a promising platform for the development of anti-viral agents against current and emerging SARS-CoV-2 variants, as well as other RNA viruses. Full article

Aberrant activation of innate immunity promotes the development of pulmonary arterial hypertension (PAH); however, the role of pattern recognition by Toll-like receptors (TLRs) within the pulmonary vasculature remains unclear. To consolidate knowledge (as of June 2025) about TLRs and their interactions with viruses in PAH and to identify therapeutic implications. A narrative review of experimental and clinical studies investigating ten TLRs in the context of the pulmonary vascular microenvironment and viral infections. Activation of TLR1/2, TLR4, TLR5/6, TLR7/8, and TLR9 converges on the MyD88–NF-κB/IL-6 axis, thereby enhancing endothelial-mesenchymal transition, smooth muscle proliferation, oxidative stress, thrombosis, and maladaptive inflammation, ultimately increasing pulmonary vascular resistance. Conversely, TLR3, through TRIF–IFN-I, preserves endothelial integrity and inhibits vascular remodeling; its downregulation correlates with PAH severity, and poly (I:C) restitution has been shown to improve hemodynamics and right ventricular function. HIV-1, EBV, HCV, endogenous retrovirus K, and SARS-CoV-2 infections modulate TLR circuits, either amplifying pro-remodeling cascades or attenuating protective pathways. The “TLR rheostat” is shaped by polymorphisms, ligand biochemistry, compartmentalization, and biomechanical forces. The balance between MyD88-dependent signaling and the TRIF–IFN-I axis determines the trajectory of PAH. Prospective therapeutic strategies may include TLR3 agonists, MyD88/NF-κB inhibitors, modulation of IL-6, and combination approaches integrating antiviral therapy with targeted immunomodulation in a precision approach. Full article

Molecular chaperones HSP70 and HSP90 represent a critical, yet conflict-ridden, node in plant physiology, particularly under the dual impact of heat stress and viral infection. As key components of both thermotolerance (maintaining proteostasis) and innate immunity (stabilization of NLR receptors), they are simultaneously exploited by viruses to facilitate their own life cycle. This review critically analyzes this “trilemma,” focusing on the hypothesis of competition for a limited chaperone pool. We present mechanistic insights indicating that during heat stress, cellular priority shifts towards maintaining global proteostasis, thereby diverting chaperones from immune functions. This resource-based competition mechanism potentially explains the collapse of ETI-immunity, as NLR receptors, deprived of support from the HSP90-SGT1-RAR1 complex, are destabilized and targeted for degradation. We also integrate adjacent signaling pathways into this model, including hormonal cross-talk (SA, JA) and autophagy. Understanding this trade-off opens new perspectives for molecular breeding and the biotechnological engineering of stress-resilient crop varieties. Full article

This study investigated proteomic differences in nasopharyngeal swabs of SARS-CoV-2-infected patients from Manaus (Brazil) who were hospitalized during the devastating first wave of the COVID-19 pandemic, before the emergence of the deadly P1 SARS-CoV-2 strain. LC-MS/MS proteomic analysis compared 16 matched COVID-19 patient profiles: eight survivors and eight fatalities. A total of 1604 proteins were identified in fatality swabs, and 981 in the swabs of survivors. Our study provides new insights into the cellular mechanisms underlying first-wave COVID-19 deaths from Manaus and identifies hypoxia-related HYOU1, endothelial injury-associated S100A10, and some viral replication proteins (DDX1/17, XPO1) as potential biomarkers of fatal infections. The proteomic profiles of the swabs taken from patients that died collectively suggest that many of the first wave COVID-19 fatalities in Manaus suffered immune-system collapse. Survivor patient swabs showed elevated levels of immune defense proteins (FN1, C4BPA, IGKV1-5), indicating effective antiviral responses. Gene ontology analysis revealed dysregulated secretory pathways in fatalities and did not detect the defense-response pathways in fatality-group datasets that were observed in survivor protein datasets. Interestingly, the NOS2 protein, previously associated with first-wave fatalities, was found exclusively in our fatality swabs. Full article

Dengue virus (DENV) affects not only peripheral immune cells but also hematopoietic progenitors in the bone marrow, particularly megakaryocytic precursors, which contribute to the thrombocytopenia characteristic of the disease. In this study, we evaluated the relationship between the differentiation status of the megakaryocytic lineage and its permissiveness and antiviral response to DENV. Our results demonstrate that the erythroid–megakaryocytic precursor (K562 cells) was more permissive to DENV infection than megakaryoblasts, as evidenced by immunofluorescence, flow cytometry, and quantification of viral particles. The antiviral response in K562 cells peaked at three days post-infection, with maximal expression of genes associated with the type I interferon (IFN-I) pathway. In vitro-induced differentiation of K562 cells reduced the initial susceptibility to DENV and enhanced the expression of Toll-like receptor 3 (TLR3) and the type I interferon receptor (IFNAR1), accelerating and intensifying IFN-β secretion, and increasing the expression of OAS2 and IRF3. Furthermore, pretreatment of K562 cells with recombinant IFN-β significantly reduced viral replication from the first day post-infection. Collectively, these findings demonstrate for the first time that the differentiation status of erythroid–megakaryocytic progenitor critically shapes their antiviral response and underscore the central role of IFN-β in the early restriction of DENV infection. Full article

African swine fever virus (ASFV) is a high-consequence pathogen that causes African swine fever (ASF), for which mortality rates can reach 90–100%, with death typically occurring within 14 days. ASF is currently a highly contagious pandemic disease responsible for extensive losses in pig production in multiple affected countries suffering from extended outbreaks. While a limited number of vaccines to prevent ASF are in use in south-east Asia, vaccines are not widely available, are only effective against highly homologous strains of ASFV, and must be used prior to an outbreak on a farm. Currently, there is no treatment for ASF and culling affected farms is the only response to outbreaks on farms to try and prevent spreading. CRISPR/Cas systems evolved as an adaptive immune response in bacteria and archaea that function by cleaving and disrupting the genomes of invading bacteriophage pathogens. CRISPR technology has since been leveraged into an array of endonuclease-based systems used for nucleic acid detection, targeting, genomic cleavage, and gene editing, making them particularly well-suited for development as sequence-specific therapeutic modalities. The programmability of CRISPR-based therapeutics offers a compelling new way to rapidly and specifically target pathogenic viral genomes simply by using different targeting guide RNAs (gRNA) as an adaptable antiviral modality. Here, we demonstrate for the first time a specific CRISPR/Cas9 multiplexed gRNA system that targets the African swine fever viral genome, resulting in sequence-specific cleavage, leading to the reduction in the viral load in infected animals, and subsequent recovery from an otherwise lethal dose of ASFV. Moreover, animals that recovered had protective immunity to subsequent homologous ASFV infection. Full article

Cardiovascular morbidity and mortality rise precipitously during the 6th–9th decades of life, identifying aging as a critical risk factor. Simultaneously, older individuals are susceptible to severe viral infection, raising the question whether shared mechanisms exist that predispose to both cardiovascular disease (CVD) and failing anti-viral immunity. The aging process causes steady decline in immune fitness (immune aging), which undermines the ability to generate protective anti-viral immune responses. Paradoxically, the aging immune system supports unopposed inflammatory pathways (inflammaging), which exacerbates tissue inflammation in CVD, specifically atherosclerosis. Here, we review the current evidence of how innate and adaptive immune aging promotes tissue-destructive inflammation in atherosclerosis while failing to fight viral infections. Further, we consider how these two disease processes mutually influence each other. We propose that mounting an effective anti-viral response induces off-target bystander activation and exhausts immune cells, ultimately exacerbating CVD. Additionally, we explore how atherosclerotic CVD impacts innate immunity through epigenetic modification of hematopoietic precursors and metabolically conditioning immune cells, leading to a dysfunctional immune system that accelerates plaque inflammation while simultaneously impairing host defense. Full article

Fullerenols are polyhydroxylated derivatives of fullerene (C₆₀(OH)_n) with antioxidant, antiviral, and antibacterial properties and potential biomedical applications due to their solubility and biocompatibility. However, comprehensive assessment of their cytotoxicity is required, particularly regarding their effects on immune system cells. This study investigated the effects of fullerenol C₆₀(OH)₂₄ (MST-Nano, St. Petersburg, Russia) on the viability, apoptosis, and metabolism of THP-1 human monocytic leukemia cells. Cells were treated with concentrations ranging from 0.25 to 1000 µg/mL and incubated for 24, 48, and 72 h. Viability, apoptosis, and nanoparticle association were assessed by flow cytometry; glycolysis and mitochondrial respiration were measured after 24 h on a Seahorse XFe96 analyzer (Agilent Technologies, Santa Clara, CA, USA). Results showed that the effects of fullerenol depend on concentration and exposure time. At 24 h, 750 µg/mL increased viability, while 1000 µg/mL induced apoptosis. After 48 and 72 h, apoptosis increased at concentrations ≥750 µg/mL, with reduced viability. Nanoparticle association correlated with concentration and inversely correlated with viability but was independent of incubation time. Metabolic analysis revealed decreased glycolysis at 750 µg/mL after 24 h, while mitochondrial respiration was unaffected. Thus, our study demonstrated that fullerenol nanoparticles were safe for the THP-1 monocytic cell line up to 500 µg/mL. Full article

Toll-like receptor 9 (TLR9) and Toll-like receptor 3 (TLR3), which are widely expressed in dendritic cells (DCs), function as key pattern recognition receptors (PRRs) in the immune system. Their primary roles involve specifically detecting pathogen-associated molecular patterns (PAMPs): TLR9 recognizes unmethylated CpG motifs predominantly found in bacterial and viral DNA, while TLR3 identifies viral double-stranded RNA (dsRNA), a molecular signature associated with viral replication. Their specific agonists [CpG ODN (a TLR9 agonist) and poly(I:C) (a TLR3 agonist)] can effectively activate DCs and enhance the expression of immune activation-related molecules. In this study, by establishing a mouse primary dendritic cell model and a glioma-bearing mouse model, and employing techniques such as transcriptome sequencing, we found that combined stimulation with CpG ODN and poly(I:C) significantly enhanced the anti-tumor function of DCs: in vitro, DCs subjected to combined stimulation showed upregulation of anti-tumor-related surface markers, enhanced migratory capacity, and a more effective activation of CD8⁺ T cells; in vivo, a DC vaccine loaded with tumor lysate antigen and stimulated with this combined regimen significantly delayed the progression of glioma in tumor-bearing mice. Further investigation revealed that the underlying mechanism for this enhanced effect may involve TLR9 activation promoting TLR3 upregulation through the p38 MAPK-ATF3 signaling axis. Consequently, we designed a sequential stimulation protocol (first CpG ODN then poly(I:C)), which demonstrated a stronger anti-glioma effect compared to simple combined stimulation. This study provides a new strategy for enhancing the immune efficacy of DC vaccines and has potential significance for promoting the clinical translation of DC vaccines. Full article

The Influenza A Virus (IAV) is known to hijack cellular proteins during its replication. IAV infection increases the expression of Heat-shock-protein family A (Hsp70) member 5 (HSPA5) in human cells, but its specific function in the viral life cycle remains unclear. This study aims to elucidate the function of HSPA5 in IAV replication, by implementing HSPA5 knockdown (KD) in A549 cells and assessing its impact on IAV’s viral protein translation, genomic RNA transcription, and the host cellular proteome. HSPA5 KD significantly reduced progeny virus release, although viral RNA levels were unaffected. Interestingly, levels of viral structural proteins increased in HSPA5 KD cells after infection. Treatment with HSPA5 inhibitor also suppressed IAV replication, confirming its role as a host dependency factor. Proteomic profiling revealed 116 proteins altered in wild-type cells and 223 in HSPA5 KD cells, with 32 uniquely dysregulated in wild-type and 139 unique to HSPA5 KD cells. In HSPA5 knockdown cells, the altered proteins were linked to pathways such as EIF2, EGF, PEDF, CNTF, IL-13, and G-protein receptor signaling, as well as to cellular processes like lymphocyte activation and regulation of immune and blood cell death, which were not affected in wild-type cells after IAV infection. Overall, this study suggests that HSPA5 contributes to late stages of IAV replication, likely assembly or maturation, and represents a promising target for antiviral drug development. Full article

Chronic inflammation constitutes a significant characteristic of sustained infections caused by viral and fungal pathogens, with a strong correlation to the development of cancer, autoimmune disorders, and tissue fibrosis. Viral proteins such as HIV-1 Tat, HBV X (HBx), HPV E6/E7, and EBV LMP1 modulate the host’s immune signaling pathways, primarily through the activation of the NF-κB signaling cascade and the disruption of cytokine equilibrium. These molecular interactions result in a pro-inflammatory microenvironment that facilitates viral persistence, immune evasion, and the process of oncogenesis. Structural investigations have elucidated the mechanisms by which these viral proteins interact with host signaling complexes, thereby highlighting their potential as viable therapeutic targets. Similarly, fungal proteins, including secreted aspartyl proteases (Saps), ribotoxin Asp f1, and chitin-binding proteins, incite chronic inflammation by activating pattern recognition receptors and triggering inflammasome activation. Despite the limited structural information of these fungal proteins, emerging models and bioinformatic analyses identified conserved motifs that are crucial for host interactions. Biologic therapies, encompassing antiviral and antifungal peptides as well as monoclonal antibodies, are currently under development to disrupt these protein-host interactions and modulate inflammatory responses. This review provides structural and functional insight into viral and fungal inflammatory proteins and evaluates the potential of biologics as targeted therapeutic interventions for chronic inflammation associated with infections. We discuss the ongoing clinical trials involving neutralizing antibodies targeting HIV, peptide vaccines aimed at HPV and other promising molecules. Finally, we discuss the current limitations of biologics and possible solutions to translate these promising therapeutics into clinical practice. Full article