AUTHOR=Azevedo Marina Luise Viola , Zanchettin Aline Cristina , Vaz de Paula Caroline Busatta , Motta Júnior Jarbas da Silva , Malaquias Mineia Alessandra Scaranello , Raboni Sonia Mara , Neto Plínio Cezar , Zeni Rafaela Chiuco , Prokopenko Amanda , Borges Nícolas Henrique , Godoy Thiago Mateus , Benevides Ana Paula Kubaski , de Souza Daiane Gavlik , Baena Cristina Pellegrino , Machado-Souza Cleber , de Noronha Lucia TITLE=Lung Neutrophilic Recruitment and IL-8/IL-17A Tissue Expression in COVID-19 JOURNAL=Frontiers in Immunology VOLUME=12 YEAR=2021 URL=https://www.frontiersin.org/journals/immunology/articles/10.3389/fimmu.2021.656350 DOI=10.3389/fimmu.2021.656350 ISSN=1664-3224 ABSTRACT=

The new SARS-CoV-2 virus differs from the pandemic Influenza A virus H1N1 subtype (H1N1pmd09) how it induces a pro-inflammatory response in infected patients. This study aims to evaluate the involvement of SNPs and tissue expression of IL-17A and the neutrophils recruitment in post-mortem lung samples from patients who died of severe forms of COVID-19 comparing to those who died by H1N1pdm09. Twenty lung samples from patients SARS-CoV-2 infected (COVID-19 group) and 10 lung samples from adults who died from a severe respiratory H1N1pdm09 infection (H1N1 group) were tested. The tissue expression of IL-8/IL-17A was identified by immunohistochemistry, and hematoxylin and eosin (H&E) stain slides were used for neutrophil scoring. DNA was extracted from paraffin blocks, and genotyping was done in real time-PCR for two IL17A target polymorphisms. Tissue expression increasing of IL-8/IL-17A and a higher number of neutrophils were identified in samples from the H1N1 group compared to the COVID-19 group. The distribution of genotype frequencies in the IL17A gene was not statistically significant between groups. However, the G allele (GG and GA) of rs3819025 was correlated with higher tissue expression of IL-17A in the COVID-19 group. SARS-CoV-2 virus evokes an exacerbated response of the host’s immune system but differs from that observed in the H1N1pdm09 infection since the IL-8/IL-17A tissue expression, and lung neutrophilic recruitment may be decreased. In SNP rs3819025 (G/A), the G allele may be considered a risk allele in the patients who died for COVID-19.