PT  - JOURNAL ARTICLE
AU  - Lucía Bañuls
AU  - Silvia Castillo
AU  - María Magallón
AU  - Daniel Pellicer
AU  - Sergi Bondia
AU  - María Mercedes Navarro-García
AU  - Cruz González
AU  - Francisco Dasí
TI  - Characterisation of alpha-1 antitrypsin protein expression and secretion in natural killer cells from healthy volunteers and alpha-1 antitrypsin deficiency patients
AID  - 10.1183/13993003.congress-2021.PA668
DP  - 2021 Sep 05
TA  - European Respiratory Journal
PG  - PA668
VI  - 58
IP  - suppl 65
4099  - http://erj.ersjournals.com/content/58/suppl_65/PA668.short
4100  - http://erj.ersjournals.com/content/58/suppl_65/PA668.full
SO  - Eur Respir J2021 Sep 05; 58
AB  - Introduction: Alpha-1 antitrypsin (AAT) protein is the most abundant protease inhibitor in serum, but it also presents immunomodulator and anti-inflammatory activity. AAT expression is codified by the SERPINA1 gene. Mutations in this gene lead to AAT deficiency (AATD), a highly underdiagnosed respiratory condition. AAT is mainly produced by hepatocytes and, in smaller quantities, by neutrophils, monocytes, or alpha and beta-pancreatic cells, among others.Natural killer cells (NK) are a type of lymphocyte of the innate immune system. Their main function is to kill infected cells and help regulate immune response by cytokine secretion.The present study aims to characterise NK cells regarding AAT expression, due to the implication of both cells and protein, in the immune system response and regulation.Methods: NK cells were isolated from whole blood by immunomagnetic negative selection from five healthy donors and seven AATD patients. Total RNA and proteins were isolated from NK cells and AAT expression was assayed by RT-qPCR and Western Blotting. To determine AAT secretion, NK cells were cultured for 72 hours and AAT levels were determined from culture supernatants by ELISA.Results: SERPINA1 gene expression was detectable by RT-qPCR, showing similar expression levels to the GAPDH constitutive gene. AAT protein was detected by western blot in cell lysates and by ELISA in culture supernatants.Conclusion: For the first time, we have shown that AAT is expressed and secreted by NK cells derived from healthy individuals and AATD patients.Funded by 2016 Sociedad Valenciana de Neumología grant, SEPAR grant, GVA grant ACIF/2019/231FootnotesCite this article as: European Respiratory Journal 2021; 58: Suppl. 65, PA668.This abstract was presented at the 2021 ERS International Congress, in session “Prediction of exacerbations in patients with COPD”.This is an ERS International Congress abstract. No full-text version is available. Further material to accompany this abstract may be available at www.ers-education.org (ERS member access only).