Differences in response to Der p1 and bacterial lipopolysaccharide in peripheral blood mononuclear cells from severe and non-severe asthmatics

Background: Asthma is heterogeneous disease with many phenotypes. Phospholipases A₂ (PLA₂) participate in production of eicosanoids–lipid mediators that modulate the chronic inflammation in asthmatics. Histone modification is a mechanism that controls the transcription of many inflammatory genes. Aim: The aim of the study was to compare the response of PBMC isolated from severe, non-severe and healthy controls to nDer p1 and LPS in relation to changes in PLA₂, histone acetylases (HAT) and deacetylases (HDAC) genes expression. Methods: Twelve severe, 15 non-severe asthmatics atopic to Der p1 and 15 healthy controls were enrolled to the study. The expression of PLA₂, HAT and HDAC were assessed in PBMC before and after stimulation with nDer p1 and bacterial lipopolysacharide. The qRT-PCR was run with TaqMan Low Density Array Cards. 2^-ΔΔCt was used to calculate changes in gene expression. Results: Patients with severe asthma characterized the increased expression of HDAC1 and PLA2G4C as well as decreased expression of EP300 and PLA2G12 in response to nDer p1. Likewise the same profile of PLA2G4C and EP300 expression was observed in severe asthmatics after LPS stimulation. Non-severe asthmatics showed decreased expression of HDAC2 and PLA2G15 in response to LPS. Conclusions: PBMC from severe and non-severe asthmatics differently response to environmental factors. Der p1 and LPS influence the expression of selected phospholipases A₂, HAT and HDAC genes in PBMC from asthmatics. Funded by Polish National Science Center grant: DEC-2012/05/N/NZ5/02630.