Expression of “non-classical” molecules of the main histocompatibility complex in rheumatoid arthritis and bronchial asthma

Abstract

HLA-E is a minor understudied non-classical HLA genes. HLA-E transcription is revealed in many cell types, especially, in immune cells, e.g., T and B cells monocytes, macrophages. In this work, we evaluated expression of HLA-E on CD8+, CD4+ and CD14+ cells in conditionallу healthy donors and in the patients with bronchial asthma (BA) and rheumatoid arthritis (RA). Peripheral blood mononuclears (PBMNC) were used as initial biomaterial. PBMNC from RA patients (n = 15), BA (n = 11) and healthy donors were separated from peripheral blood in Ficoll-Urographin density gradient (1.077 g/mL). The cells were then stained with fluorochrome-conjugated monoclonal antibodies: anti-CD3-APC, anti-CD4-APC-Cy7, anti-CD-14-FITC, and anti-HLA-E-PerCP/Cy5. The cell phenotype was analyzed by flow cytometry with FACS Canto II (BD Biosciences, USA). We have found an increased expression of HLA-E on CD8+, CD4+Т cells, like as on CD14+ cells (monocytes) in the RA patients, when compared with BA patients. We have also shown significant differences of HLA-E expression on CD8+Т cells between the conditionally healthy donors and RA patients.