AUTHOR=Queiroz Maria Alice Freitas , Santiago Angélica Menezes , Brito Wandrey Roberto dos Santos , Pereira Keise Adrielle Santos , de Brito William Botelho , Torres Maria Karoliny da Silva , Lopes Jeferson da Costa , Santos Erika Ferreira dos , da Costa Flávia Póvoa , de Sarges Kevin Matheus Lima , Cantanhede Marcos Henrique Damasceno , de Brito Mioni Thieli Figueiredo Magalhães , da Silva Andréa Luciana Soares , Leite Mauro de Meira , Viana Maria de Nazaré do Socorro de Almeida , Rodrigues Fabíola Brasil Barbosa , da Silva Rosilene , Viana Giselle Maria Rachid , Chaves Tânia do Socorro Souza , Veríssimo Adriana de Oliveira Lameira , Carvalho Mayara da Silva , Henriques Daniele Freitas , Santos Carla Pinheiro dos , Nunes Juliana Abreu Lima , Costa Iran Barros , Amoras Ednelza da Silva Graça , Lima Sandra Souza , Cayres-Vallinoto Izaura Maria Vieira , Brasil-Costa Igor , Quaresma Juarez Antônio Simões , Falcão Luiz Fábio Magno , Santos Eduardo José Melo dos , Vallinoto Antonio Carlos Rosário TITLE=Polymorphisms in the MBL2 gene are associated with the plasma levels of MBL and the cytokines IL-6 and TNF-α in severe COVID-19 JOURNAL=Frontiers in Immunology VOLUME=14 YEAR=2023 URL=https://www.frontiersin.org/journals/immunology/articles/10.3389/fimmu.2023.1151058 DOI=10.3389/fimmu.2023.1151058 ISSN=1664-3224 ABSTRACT=Introduction

Mannose-binding lectin (MBL) promotes opsonization, favoring phagocytosis and activation of the complement system in response to different microorganisms, and may influence the synthesis of inflammatory cytokines. This study investigated the association of MBL2 gene polymorphisms with the plasma levels of MBL and inflammatory cytokines in COVID-19.

Methods

Blood samples from 385 individuals (208 with acute COVID-19 and 117 post-COVID-19) were subjected to real-time PCR genotyping. Plasma measurements of MBL and cytokines were performed by enzyme-linked immunosorbent assay and flow cytometry, respectively.

Results

The frequencies of the polymorphic MBL2 genotype (OO) and allele (O) were higher in patients with severe COVID-19 (p< 0.05). The polymorphic genotypes (AO and OO) were associated with lower MBL levels (p< 0.05). IL-6 and TNF-α were higher in patients with low MBL and severe COVID-19 (p< 0.05). No association of polymorphisms, MBL levels, or cytokine levels with long COVID was observed.

Discussion

The results suggest that, besides MBL2 polymorphisms promoting a reduction in MBL levels and therefore in its function, they may also contribute to the development of a more intense inflammatory process responsible for the severity of COVID-19.