Distinct expression of the inhibitory receptor LAIR-1 on circulating neutrophils from severely RSV-infected children

SEERY V; HOLGADO P; SANANEZ I; ARRUVITO L; RAIDEN S; GEFFNER J

Tucuman

Congreso; Reunión Anual SAI 2019; 2019

SAI

Background and aim: Respiratory syncytial virus (RSV) is the leading cause of bronchiolitis in young children worldwide. Neutrophils are crucial to antimicrobial defense, but excessive neutrophilic inflammation induces lung damage. Leukocyte-associated immunoglobulin-like receptor (LAIR)-1 functions as an inhibitory receptor when co-engaged with activating receptors. Here we aim to investigate the expression and function of LAIR-1 in neutrophils (Neu) from RSV-severely infected children.Specific aims:1- To analyze the basal expression of LAIR-1 on Neu from RSV-infected. 2- To examine whether Neu increase LAIR-1 expression after in vitro exposition to RSV and/or type IV collagen (a specific ligand, IV Co). 3 - To explore the biologic response of Neu upon ligation with anti-LAIR-1 in presence of activating stimulus as coated IgG (cIgG) and/or IV Co.Results: We observed an increased frequency of LAIR-1+ Neu in RSV-infected (10.6%±5.9; n=7) compared with healthy infants (1.4%±0.8; n=5), p