The role of IL17 and IL17RA polymorphisms in lethal pandemic acute viral pneumonia (Influenza A virus H1N1 subtype)

Abstract

Background The cytokines play an essential role in acute inflammatory processes, and the IL-17 may be responsible for ambiguous aspects, and the correlation with genetic polymorphisms could improve the search for this critical biomarker. Thus, this study aimed to evaluate the IL-17A and IL-17RA tissue expression and the polymorphisms that codified these proteins in a population that died of pandemic Influenza A virus H1N1 subtype compared to a non-pandemic Influenza virus population. Methods Necropsy lung samples immunohistochemistry was performed to assess the presence of IL-17A and IL-17RA in the pulmonary tissue. Eight single nucleotide polymorphisms were genotyped using TaqMan® technology. Results The Influenza A H1N1 pandemic group had higher tissue expression of IL-17A, higher neutrophil recruitment and shorter survival time between admission and death. Three single nucleotide polymorphisms conferred risk for pandemic influenza A H1N1, the AA genotype of rs3819025 G/A, the CC genotype of rs2241044 A/C, and the TT genotype of rs 2,241,043 C/T. Conclusions One IL17A polymorphism (rs381905) and two IL17RA polymorphisms (rs2241044 and rs2241043) represented biomarkers of worse prognosis in the population infected with pandemic influenza A H1N1. The greater tissue expression of IL-17A shows a Th17 polarization and highlights the aggressiveness of the pandemic influenza virus with its duality in the protection and pathogenesis of the pulmonary infectious process.

Impact of Interleukin-17 Receptor A Gene Variants on Asthma Susceptibility and Clinical Manifestations in Children and Adolescents

“…Although several SNPs related to IL-17A have been linked to susceptibility of a variety of immune-mediated/inflammatory disorders [ 38 , 39 , 40 , 41 , 42 , 43 , 44 ], including asthma [ 45 , 46 , 47 , 48 , 49 ], with potential modification of related gene expression and Th17 cells activities [ 40 , 50 ], no previous studies have explored the potential role of IL17RA gene variants in asthma susceptibility, in particular in our population. In this sense, the current study was designed to investigate for the first time the association between four SNPs (i.e., rs4819554, rs879577, rs41323645, and rs4819555) in IL-17RA and asthma susceptibility/phenotype in our region.…”