Rheumatoid Arthritis (RA) is a multifactorial autoimmune disease. Currently, several genes play an important role in the development of the disease. The objective was to evaluate the association of the STAT4 rs7574865 and rs897200 gene variants with RA susceptibility, DAS28, RF, and anti-CCP in Western and Southern Mexico populations. Genotyping was performed on 476 samples (cases = 240; controls = 236) using the Taqman^® system and qPCR probes. Disease activity was assessed using DAS28 and HAQ DI. CRP, ESR, RF, and anti-CCP were determined for clinical assessment. Our study showed there is a statistically significant association with susceptibility to RA for the rs7574865 variant in the Western population for the GT and TT genotypes. The same genotypes also showed a moderate-to-high activity according to DAS28 and positive anti-CCP compared to the control group. This association was not found in the Southern population. This work confirms the association of the rs7574865 variant with RA, as well as a moderate-to-high activity and positive anti-CCP in the Western population but not in the Southern population. No association of the rs897200 variant was found in any of the studied populations.

Background: The STAT4 gene plays a key role in immune regulation and is associated with susceptibility to autoimmune diseases such as rheumatoid arthritis (RA) and systemic lupus erythematosus (SLE). Objectives: The objective of this study is to analyze variants of uncertain significance (VUSs) in STAT4 using bioinformatics tools to predict their functional and structural impact. Methods: A total of 48,295 variants of the STAT4 gene (ENSG00000138378) were retrieved from the Ensembl database. A tiered filtering approach was used to assess VUS pathogenicity, integrating in silico prediction tools such as SIFT, PolyPhen, MutPred2, and Align-GVGD, as well as structural modeling platforms including Chimera, ModRefiner, Missense3D, HOPE, and DynaMut2. Results: Eighty missense VUSs were identified; of these, 13 were prioritized based on concordant signals across multiple computational predictors. These variants showed significant alterations in the physicochemical properties of the protein, including changes in hydrophobicity and disruption of hydrogen bonding. Notably, the rs140675301 (Glu128Val) variant lies within a conserved loop, and in silico analyses suggest that this mutation may alter kinase specificity regarding the phosphorylation of serine 130. Conclusions: The integrative use of the bioinformatic tools employed represents a valuable preliminary step prior to undertaking more complex and resource-intensive functional studies. This complementary strategy strengthens the interpretative framework for VUS, guiding subsequent experimental validation and supporting a structured assessment of variant relevance, particularly in the context of immune-related genes such as STAT4.

Rheumatoid arthritis (RA) is characterized by chronic inflammation mediated by the JAK/STAT pathway. Variants in STAT4 have been associated with autoimmune susceptibility, but their functional role in RA remains unclear. The aim of this study was to genetically and functionally characterize STAT4 in RA patients with varying disease activity by analyzing two variants, mRNA expression, phosphorylated STAT4 (pSTAT4), and inflammatory cytokines (IL-12, IL-23, and IFN-γ). Sixty-three Mexican patients with RA were stratified into remission/low and moderate/high activity groups. Genotyping, STAT4 mRNA expression, pSTAT4 quantification, cytokine profiling, and treatment analyses were conducted. Patients receiving methotrexate, hydroxychloroquine, and sulfasalazine had higher IL-12 concentrations compared with those on other regimens. In remission/low activity patients, GC/GC carriers exhibited increased IL-12, PBMC levels, and anti-CCP antibodies, while GC/TT carriers in the moderate/high activity group showed distinct ESR values. Secondary analyses revealed that TT/TT carriers with STAT4 overexpression exhibited higher IFN-γ and IL-23 levels. IL-12 differences persisted among GC/GC carriers regardless of STAT4 expression status. In conclusion, these exploratory findings suggest potential interactions among STAT4 haplotypes, expression status, and treatment regimens influencing cytokine and inflammatory profiles in RA. However, due to the small subgroup sizes, the observed associations should be interpreted with caution and considered hypothesis-generating until validated in larger cohorts.

Human adenovirus 36 (HAdV-36) is associated with obesity, potentially by promoting adipocyte proliferation and differentiation. Although linked to increased fat storage, HAdV-36 is also correlated with improved insulin sensitivity. Given its potential role in modulating adipose tissue and promoting a less inflammatory metabolic profile, its impacts on pro- and anti-inflammatory cytokine secretion remain unclear. Methods: This nested case-control study compared cytokine levels (IL-10, IL-2, IL-6, IL-8, and TNF-α) between patients with and without HAdV-36 infection. A total of 76 participants were included, with 37 in the control group (HAdV-36 negative) and 39 classified as cases (HAdV-36 positive). Results: HAdV-36 seropositive individuals exhibited significantly lower IL-6 levels and higher IL-8 levels than seronegative participants. Additionally, they had lower glucose levels, suggesting a potential link between HAdV-36 and metabolic regulation. Conclusions: These findings support the hypothesis that HAdV-36 may influence inflammatory and metabolic responses by modulating cytokine expression and glucose levels. Further research is needed to clarify the underlying mechanisms and their implications for metabolic health.

Background/Objectives: Postoperative atrial fibrillation (POAF) is a common complication after cardiac surgery with cardiopulmonary bypass (CPB), increasing morbidity and prolonging hospitalization. This study aimed to develop and validate an exploratory prediction model that integrates perioperative inflammatory biomarkers with clinical and surgical variables to identify patients at risk of early POAF. Methods: A prospective exploratory cohort of 89 patients undergoing coronary artery bypass grafting (CABG; n = 36), valve surgery (n = 40), or CABG–valve surgery (n = 13) was evaluated. Clinical, surgical, and proinflammatory serum biomarkers (IL-6, IL-8, IL-10, and CRP) were recorded preoperatively (T1) and at 24 h (T2) and 48 h (T3) postoperatively. Multiple-comparison adjustments were made using the Benjamini–Hochberg false discovery rate. Predictor selection was based on bootstrap-derived stability using LASSO-penalized logistic regression, and the final model was estimated using Firth’s bias-reduced logistic regression. Results: POAF incidence was 8.3% in CABG, in contrast to 22.5% and 30.8% in valve and CABG-valve surgeries, respectively. After multiple-comparison corrections, only IL-6 at T2 postoperatively was significantly higher in patients who subsequently developed POAF. Bootstrap-based stability selection retained T2 postoperative IL-10 and magnesium concentrations in the final model, which achieved an apparent AUC of 0.776 and a bootstrap optimism-corrected AUC of 0.728, with acceptable calibration (Brier score = 0.103), negligible multicollinearity (VIF = 1.04), and a negative predictive value of 95.5% at the optimal Youden threshold. Conclusions: Our findings support an exploratory prediction model with moderate discrimination for POAF after cardiac surgery with CPB, providing a methodological foundation for future multicenter validation studies.