A preliminary study of serum class II levels in healthy individuals and bone-marrow transplant patients

Abstract A double-determinant ELISA has been developed to measure class II major histocompatibility complex molecules in blood from healthy individuals and patients who received either an allogeneic or an autologous bone-marrow transplant. Levels were higher in pre-transplant patients than in healthy individuals, and in the majority of patients, these levels rose even higher at 4 weeks post-transplantation. At later times after transplantation, it was difficult to draw firm conclusions, because the number of values available were too limited. Nevertheless, in the autologous group with no graft-versus-host disease (GVHD), levels were consistently lower at 6 months and one year; in the allogeneic group these long-term levels varied. As class II antigens are expressed on skin and rectal epithelia in GVHD, this study suggests that serial measurement of serum class II levels may be useful for monitoring GVHD in bone-marrow transplantation.