The Loss of Ia+ Langerhans' Cells During Graft-Nersus-Host Disease in Rats

The effects of graft-versus-host-disease (GVHD) on different tissues and cells were studied. High and low lymphocyte doses were employed for the induction of GVHD, and the results were compared. It was shown that ear skin was more susceptible to attack than abdominal skin. It is speculated that this could be due to the different vascular networks in the two areas. Weight loss, skin erythema, splenomegaly, histology, and Langerhans' cell density were used to assess GVHD. The Langerhans' cell density was assessed using the Ia antigen cell marker. It is shown that Langerhans' cell density is a sensitive index for confirming GVHD. Weight loss is the least sensitive indicator. The features of GVHD occurred earlier and were more severe in animals receiving the higher dose of lymphocytes, with Ia antigen appearing on the keratinocytes in the later stages of the disease. We conclude that Langerhans' cells are sensitive to the effects of GVHD and that they can provide a diagnostically useful indicator of the disease.