Immuno, Volume 4, Issue 2 (June 2024) – 4 articles

Various vaccine platforms have been approved for broad use to prevent the transmission of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) infection. However, these vaccines exhibit distinct differences in immunogenicity and efficacy, which decline after vaccination and are further exacerbated by the emergence of virus variants and mutants. This study reports the immunization outcomes against the SARS-CoV-2 virus by assessing the immune responses and safety of different SARS-CoV-2 vaccines co-administered in BALB/c mice. Vaccine combinations comprising mRNA/adenovirus26-vector, mRNA/inactivated, adenovirus26-vector/inactivated, and mRNA/adenovirus26-vector/inactivated vaccines were prepared in optimized doses, and their activities upon immunization evaluated in comparison with individual mRNA, adenovirus26-vectored, and inactivated vaccines. Fourteen- and 28-days post-immunization, we measured spike-specific IgG response using Enzyme-Linked Immunosorbent Assay (ELISA), cytokine expression profiles through Quantitative real-time polymerase chain reaction (RT-PCR), and evaluated safety through histopathological examination. The mRNA/Vector/Inactivated group exhibited slightly higher anti-spike IgG levels, albeit not statistically significant (p > 0.132). Importantly, this regimen induced elevated IL-6 and IFN-γ mRNA expression levels (p < 0.0001) compared to immunization with individual vaccines. In summary, this study demonstrated that co-administering the mRNA/adenovirus26 vector/inactivated SARS-CoV-2 vaccines improved spike-specific IgG response, triggered significantly enhanced IL-6 and IFN-γ mRNA expression levels, and proved safe in mice. Full article

Chronic hepatitis B (CHB) poses treatment challenges, with treatment response and disease outcome often determined by the immune response, particularly mononuclear phagocytes. Monocytes can differentiate into various subpopulations influenced by AHR. Statins, known for inflammation modulation, may impact monocyte function via AHR activation. This study explored rosuvastatin (RSV)’s effects on monocyte subtypes, inflammatory markers, and AHR in CHB patients. Fifteen CHB patients were randomly assigned to receive either 20 mg RSV or a placebo daily for three months. Flow cytometry assessed CD14+ CD16− (classical), CD14+ CD16+ (intermediate), and CD14dim CD16+ (patrolling) monocyte subtypes, along with AHR levels in each subset. ELISA quantified cytokines IL-6, IFN-γ, IL-12, IL-10, TNF-α, TGF-β, and IL-1β. RSV expanded CD14+ CD16− classical and reduced CD14+ CD16+ intermediate monocytes in CHB patients while increasing AHR+ cell percentages in all subsets. RSV treatment upregulated key AHR target genes (Cyp1a1, Cyp1b1, and ARNT), indicating robust AHR signaling activation. It also reduced pro-inflammatory cytokine levels (IL-6, IFNγ, IL-12, TNF-α) and elevated anti-inflammatory cytokines (IL-10, TGF-β). Thus, RSV may modulate the immune response by altering monocyte subtypes in CHB patients via AHR activation. Full article

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection has had a global impact and resulted in millions of deaths worldwide. The course of the Janus kinase signaling transducers and activators (JAK-STAT) pathway is an important molecular pathway that is involved in the cellular response to various cytokines and growth factors promoting an inflammatory response. The overactivation of the JAK-STAT signaling pathway in coronavirus disease 2019 (COVID-19) and its effect on acute respiratory distress syndrome (ARDS)-induced inflammatory processes was observed in various clinical articles that focused on JAK-STAT regulation regarding angiotensin converting enzyme 2 (ACE2) expression and cytokine storm release. Down-regulation of the JAK-STAT signaling pathway through inhibitors decreases the inflammatory response by decreasing cytokine storm release. However, the increased regulation of JAK-STAT in severe COVID-19 patients caused cytokines such as interferon alpha (IFN-α) to promote the phosphorylation of STATs. This response indicated an imbalance with JAK-STAT regulation and its inability to induce the transcription of interferon stimulated response elements. Furthermore, an increase in ACE2 regulation was noted to also increase JAK-STAT signaling, yet the down-regulation of JAK-STAT signaling can result in the overexpression of ACE2 by binding to SARS-CoV-2 and increasing STAT1 expression. Data suggest that inflammatory cytokines enhance the activation of ACE2 in endothelial cells via JAK-STAT pathway. Increasing the regulation of the JAK-STAT signaling pathway enhances the release of cytokines such as tumor necrosis factor alpha (TNF-α) and interferon gamma (IFN-γ), further expressing ACE2. The expression of ACE2 regulates STAT1 and STAT2 expression, leading to the up-regulation of the inflammasomal complexes in hyper-inflammatory responses from the JAK-STAT pathway. Through the review of various clinical reports, the effect of the JAK-STAT signaling pathway on ARDS-induced inflammatory response was observed and correlated with the expression of ACE2 and cytokine storm release in severe COVID-19 cases. Full article

Resveratrol and its derivative piceid exhibit a wide spectrum of health-promoting bioactivities. A resveratrol-enriched variety of Dongjin rice (DJ526) has been developed by transfection of a resveratrol biosynthesis gene, and increased resveratrol content has been confirmed in seeds following germination. In the current study, these resveratrol-enriched seeds were induced to produce callus, and callus extracts were evaluated for in vitro anti-inflammatory activity. Callus cultures contained greater amounts of resveratrol and piceid than DJ526 seeds, and treatment with DJ526 callus extract significantly reduced the lipopolysaccharide (LPS)-induced production of proinflammatory mediators nitric oxide and prostaglandin E2 by RAW264.7 macrophages. The inflammation-related nuclear factor kappa B and mitogen-activated protein kinase pathways were also inhibited in DJ526 callus extract-treated RAW264.7 cells, resulting in downregulation of proinflammatory factor genes COX-2, iNOS, IL-1β, IL-6, and TNF-α. Expression of the LPS-binding toll-like receptor-4 was also markedly reduced in DJ526 callus extract-treated cells compared to DJ callus extract-treated cells. These findings demonstrate increased resveratrol and piceid content by callus culture of DJ526 rice seeds and the potent anti-inflammatory activity of resveratrol-enriched callus extract. Full article