Mechanism of human leukocyte antigen-G inhibiting T cell immune function in triple-negative breast cancer

Objective To investigate the mechanism of human leukocyte antigen-G (HLA-G) expression and T cells activation in triple-negative breast cancer(TNBC) cells to exert immunosuppressive function. Methods From three groups of breast cancer cell lines（MDA-MB-231，HCC1937， MDA-MB-468）,real-time quantitative polymerase chain reaction (RT-qPCR) and Western blot were detected and screened that the breast cancer cell line was HCC1937,which with high expression of HLA-G, and low expression of fibrinogen-like protein 1 (FGL1), programmed death factor ligand 1 (PD-L1), as well as sialic acid-binding immunoglobulin-like lectin 15 (SIGLEC15) . HCC1937 cells were divided into NC group (control group) and KD group (knockdown group), and RNA interference (RNAi) lentiviral vectors were constructed and transfected into KD cells to knock down HLA-G gene, and the verification was carried out. HCC1937 cells were treated with HLA-G antibody blocking/nonblocking, and Jurkat cells were treated with CD3 and CD28 activation/non-activation