Effect of rs4719839 polymorphism on risk of ventilator-associated pneumonia, expression of microRNA-148 and autophagy-related 16-like 1 (ATG16L1).

MiR-148 is a negative regulator of autophagy 16-like 1 (ATG16L1), a gene implicated in the pathogenesis of ventilator-associated pneumonia (VAP). Therefore, the role of miR-148 polymorphism in the pathogenesis of VAP was studied here. The expression of miR-148, ATG16L1, Beclin-I, LC3-II, TNF-α and IL-6 in serum and peripheral blood mononuclear cells (PBMCs) of VAP patients was detected to study their relationship in the pathogenesis of VAP. Chronic obstructive pulmonary disease patients carrying the AA/AG genotypes of miR-148 rs4719839 single nucleotide polymorphism (SNP) were more prone to VAP due to the higher expression of miR-148, TNF-α and IL-6 along with suppressed expression of ATG16L1, Beclin-I and LC3-II in their serum and PBMCs. Transfection of miR-148 mimics to primary PBMCs genotyped as GG and AA decreased the expression of ATG16L1, Beclin-I and LC3-II. Finally, cells carrying the AA genotype of rs4719839 SNP were more sensitive to the role of LPS stimulation in suppressing ATG16L1, Beclin-I and LC3-II expression while activating TNF-α and IL-6 expression. Our work presented detailed evidence, suggesting that the rs4719839 polymorphism can affect the risk of VAP.