SERUM HLA CLASS-I ANTIGEN LEVELS IN ALLOGENEIC BONE-MARROW TRANSPLANTATION - A POSSIBLE MARKER OF ACUTE GVHD

The levels of serum HLA class I antigens were determined at weekly int ervals up to 5 weeks in 46 patients who had undergone allogeneic BMT, In patients with GVHD grade I or with GVHD grade I and fever of unknow n origin (FUO), serum HLA class I antigen levels did not change during the observation period, In patients with GVHD grade II-IV serum HLA c lass I antigen level significantly increased in the week before the on set of GVHD, was maximal at the onset of GVHD and then persisted uncha nged in the following 2 weeks, In patients with GVHD grade I or GVHD g rade II-IV and infections whose onset coincided with that of acute GVH D a significant increase of serum HLA class I antigen level was found 2 weeks after the onset of the infectious episode, An increase of seru m KLA class I antigen level was also found before the onset of repetit ive GVHD grade II-IV episodes as well as during and after infectious e pisodes whose onset occurred after the onset of acute GVHD, The mean /- s.d. concentrations of serum HLA class I antigens during GVHD grade II-TV episodes (9.4 +/- 3.4 mu g/ml) and 2 weeks after the onset of i nfectious episodes (7.1 +/- 1.6 mu g/ml) are significantly (P < 0.01 a nd P < 0.05, respectively) higher than that found 2 weeks before the o nset of GVHD (3.0 +/- 0.5 mu g/ml). The results of the present investi gation suggest that measurement of serum HLA class I antigen level may be a possible marker to detect an acute GVHD following BMT.