Relationship Between The Expression Of ICOS On Peripheral Blood CD4～+ And CD8～+T Cells And Acute Graft-versus-host Disease After Allogeneic Hematopoietic Stem Cell Transplantation

Objective To investigate relationship between the expression of Inducible costimulator(ICOS) and acute graft-versus-host disease(aGVHD) after allogeneic peripheral blood stem cell transplantation. Methods A total of 23 patients undergoing allogeneic peripheral blood stem cell transplantation(allo-PBSCT) were included in this study. The quantity of ICOS expressed on T lymphocytes from peripheral blood was measured using FACSCalibur at different time after allo-PBSCT. The results were compared between those with aGVHD and those without aGVHD. Result All patients achieved engraftment with 8 patients developed aGVHD including 2 patientswith I° aGVHD and 6 patients with II° —III° aGVHD. The quantity of ICOS expressed on T lymphocytes from peripheral blood of patients with aGVHD is significantly higher than those without aGVHD. Conclusion The costimulator ICOS plays an important role in the development of human aGVHD. The quantity of ICOS expressed on T-lymphocyte is positively correlated to the development of human aGVHD.