Association of circulating immune complexes containing bovine proteins and graft-versus-host disease.

Chronic graft-versus-host disease (GVHD) is a complex immunological disease which can appear in up to 30% of survivors of allogeneic bone marrow transplantation. Target organs include skin, mucous membranes and liver; eventual mucosal defects, specifically involving secretory IgA, have been observed. In these studies we show that transplant recipients who develop GVHD are more likely to have higher serum antibody titres to bovine casein and circulating immune complexes containing casein than patients who do not develop this complication. The stage of GVHD may be related to the level of antibody to casein. The biological role of immune complexes in relationship to the evolution of this disease is unknown.