[Role of membrane-bound human leukocyte antigen G in inducing immune tolerance after allogeneic hematopoietic stem cell transplantation].

Objective To evaluate the role of human leukocyte antigen G (HLA-G) in the better effect of allogenetic bone marrow transplantation than that of peripheral blood stem cell transplantation. Methods Flow cytometry was used to detect the expression of membrane-bound HLA-G (mHLA-G) on donor peripheral blood (PBC) or bone marrow (BM) mononuclear cells. The levels of soluble HLA-G (sHLA-G) in the plasma and bone marrow fluid were determined using enzyme-linked immunosorbent assay (ELISA) before and after granulocyte colony-stimulating factor (G-CSF) mobilization. Results The mean levels of mHLA-G after G-CSF mobilization in the PBC and BM were significantly higher than that before G-CSF mobilization (P=0.001 and 0.000), but the plasma levels of sHLA-G showed no significant changes after the mobilization (P=0.279). The mean levels of sHLA-G in the BM fluid significantly increased (P=0.002) to a level higher than that in the PBC after G-CSF mobilization (P=0.004). Conclusion HLA-G plays an important role in immune tolerance after hematopoietic stem cell transplantation with G-CSF mobilization.