Cell surface markers and circulating cytokines in graft versus host disease

Graft versus host disease (GVHD) remains the major obstacle to the widespre ad application of allogeneic bone marrow transplantation (BMT) despite impr ovement in drug prophylaxis. T cells in the donor bone marrow recognize and react against host alloantigens and thereby initiate GVHD, but the precise ,mechanisms by which host. tissues are damaged remain unclear. In the curre nt study, we determined the cytokine secretion, cell population distributio n, and cell surface markers expression by ELISA and flow cytometer, to unde rstand further the pathophysiology of GVHD. Our results demonstrated that t here was no significant change in the cell ratio of B-and T- lymphocytes, a nd helper/suppressor cells during GVHD development when compared to the con dition before transplantation. Furthermore, the percentage of natural kille r cells, the interleukin-2 receptor (IL-2R) or the HLA-DR antigen on both C D4 and CD8 positive cells presented no significant difference between pre-t ransplantation and during GVHD. The serum cytokine secretion of IL-I, TNF-a lpha, IL-2, ICAM-1, endothelin, TGF-beta showed no difference before BMT an d during GVHD. However, when patients in the developing of GVHD, there was significant difference in the serum levels of soluble IL-2R (sIL-2R), epide rmal growth factor (EGF), and platelet derived growth factor (PDGF). In add ition, with patients who develop GVHD, the mixed lymphocyte reaction also p resented a significant difference. This study indicated that some serum cyt okines such as sIL-2R, growth factors, and the mixed lymphocyte reaction ma y be used as parameters for the early detection of the development of GVHD.