Introduction: The purpose of this study was to investigate the association between HLA-DRB1 alleles with susceptibility to rheumatoid arthritis (RA) and production of antibodies against citrullinated proteins (ACPA) and rheumatoid factor (RF). Methods: We studied 408 patients (235 with RA, 173 non-RA) and 269 controls. ACPA, RF and HLA-DR typing were determined. Results: We found an increased frequency of HLA DRB1 alleles with the shared epitope (SE) in ACPA-positive RA. Inversely, HLA DRB1 alleles encoding DERAA sequences were more frequent in controls than in ACPA-positive RA, and a similar trend was found for HLA DR3. However, these results could not be confirmed after stratification for the presence of the SE, probably due to the relatively low number of patients. These data may suggest that the presence of these alleles may confer a protective role for ACPA-positive RA. In RA patients we observed association between SE alleles and ACPA titers in a dose-dependent effect. The presence of HLA DR3 or DERAA-encoding alleles was associated with markedly reduced ACPA levels. No association between RF titers and HLA DR3 or DERAA-encoding alleles was found. Conclusions: HLA DRB1 alleles with the SE are associated with production of ACPA. DERAA-encoding HLA-DR alleles and HLA DR3 may be protective for ACPA-positive RA.

The vaccines designed against the SARS-CoV-2 coronavirus are based on the spike (S) protein. Processing of the S protein by antigen-presenting cells (APC) and its subsequent presentation to T cells is an essential part of the development of a humoral response. HLA-class II alleles are considered immune response genes because their codified molecules, expressed on the surface of APCs (macrophages, dendritic, and B cells) present antigenic peptides to T cell via their T cell receptor (TCR). The HLA-class II genes are highly polymorphic, regulating what specific peptides induce follicular helper T cells (TFH) and promote B lymphocyte differentiation into plasma or memory B cells. This work hypothesizes that the presence of certain HLA-class II alleles could be associated with the intensity of the humoral response (amount, length) to the SARS-CoV2 mRNA 1273 vaccine. We have studied the relationship between the HLA-class II typing of 87 health workers and the level of antibodies produced 30 days after vaccination. We show a possible association between the HLA-DRB1* 07:01 allele and the HLA-DRB1*07:01~DQA1*02:01~DQB1*02:02 haplotype to a higher production of antibodies 30 days after the administration of the second dose of mRNA-1273.

Human leukocyte antigen (HLA) plays an important role in immune responses to infections, especially in the development of acquired immunity. Given the high degree of polymorphisms that HLA molecules present, some will be more or less effective in controlling SARS-CoV-2 infection. We wanted to analyze whether certain polymorphisms may be involved in the protection or susceptibility to COVID-19. We studied the polymorphisms in HLA class I (HLA-A, -B and -C) and II (HLA-DRB1 and HLA-DQB1) molecules in 450 patients who required hospitalization for COVID-19, creating one of the largest HLA-typed patient cohort to date. Our results show that there is no relationship between HLA polymorphisms or haplotypes and susceptibility or protection to COVID-19. Our results may contribute to resolve the contradictory data on the role of HLA polymorphisms in COVID-19 infection.

Autoimmune diseases with elevated circulating autoantibodies drive tissue damage and the onset of disease. The Fcγ receptors bind IgG subtypes modulating the clearance of circulating immune complexes (CIC). The inner ear damage in Ménière's disease (MD) could be mediated by an immune response driven by CIC. We examined single-nucleotide polymorphism (SNPs) in the CD16A and CD32 genes in patients with MD which may determine a Fcγ receptor with lower binding to CIC.

Purpose. Previous studies have shown that melanoma cells produce excessive levels of cytokines, which have various biological roles during melanoma development. The aim of this study was to expand the profile of serum cytokines, chemokines, growth factors, and angiogenic factors that are associated with melanoma, to find more cytokines with abnormal concentrations in melanoma patients, to identify whether the level of cytokines correlated with prognostic variants, such as Breslow thickness and BRAF mutation, and, finally, to find out the cytokines that play important roles during melanoma development. Materials and Methods. Multiplex immunobead assay technology and 45-plex immunoassays ProcartaPlex™ kits were used to simultaneously compare the levels of cytokines, growth factors, angiogenic factors, and chemokines between the serum of healthy patients (n = 30) and those with melanoma (n = 72). Data were analyzed according to the clinical characteristics of the designated patient subgroups. Results. Compared to the control group, melanoma patients had higher levels of VEGF-A, PDGF-BB, IL-1RA, PIGF-1, IFN-γ, TNF-α, MIP-1α, and SCF, but lower levels of BDNF, SDF-1α, MCP-1, Eotaxin, EGF, and IL-7. Furthermore, the levels of TNF-α ( , r = 0.019), IFN-γ ( , r = 0.023), VEGF-A ( , r = 0.337), and BDNF (0.004, r = −0.391) showed a significant correlation with Breslow thickness. IL-7 was of lower levels in patients harboring BRAF mutants. Melanoma patients with high levels of MIP-1α and MCP-1 showed the poorest overall survival. Conclusions. We found that the levels of VEGF-A and PDGF-BB in the serum of both primary and metastatic melanoma patients are elevated. TNF-α, IFN-γ, and VEGF-A presented a positive correlation with Breslow thickness, whereas BDNF showed a negative association. MIP-1α and MCP-1 correlated negatively with survival. In addition, lower levels of IL-7 were found in patients harboring BRAF mutants. These findings indicate that these cytokines may play critical roles in the progression of melanoma.