https://www.selleckchem.com/products/nvp-dky709.html We took advantage of the 2015-2016 Brazilian arbovirus outbreak (ZIKV/DENV/CHIKV), associated with neurological complications, to type HLA-DRB1/DQA1/DQB1 variants in patients exhibiting neurological complications and in bone marrow donors from the same endemic geographical region. . DRB1/DQA1/DQB1 loci were typed using sequence-specific oligonucleotides. In silico studies were performed using X-ray resolved dimer constructions. The DQA1*01, DQA1*05, DQB1*02 or DQB1*06 genotypes/haplotypes and DQA1/DQB1 haplotypes that encode the putative DQA1/DQB1 dimers were overrepresented in the whole group of patients and in patients exhibiting peripheral neurological spectrum disorders (PSD) or encephalitis spectrum disorders (ESD). The DRB1*04, DRB1*13 and DQA1*03 allele groups protected against arbovirus neurological manifestation, being underrepresented in whole group of patients and/or ESD, PSD groups. Genetic and in silico studies revealed that DQA1/DQB1 dimers i) were primarily associated with susceptibility to arbovirus infections, ii) can bind to a broad range of ZIKV peptides (235 out of a library of 1,878 peptides, stressing prM and NS2A), and iii) exhibited hydrophilic and highly positively charged grooves when compared to the DRA1/DRB1 cleft. The protective dimer (DRA1/DRB1*04) bound a limited number of ZIKV peptides (40 out of 1,878 peptides, primarily prM). Protective haplotypes may recognize arbovirus peptides more specifically than susceptible haplotypes. Protective haplotypes may recognize arbovirus peptides more specifically than susceptible haplotypes. This commentary addresses the state of the evidence on tobacco products, nicotine, and COVID-19. The evidence of the effects of smoking on respiratory infections and the immune system in general are examined and the current understanding of tobacco products and risk for SARS-CoV-2 infection and the course of COVID-19 is addressed. This commentary addresses th