IgE allotypes in sera of mice with autoimmune diseases and in mice with graft-versus-host disease after transfusion or bone marrow transplantation.

Isotype- and allotype-specific IgE determinations by sandwich ELISA with monoclonal antibodies to Igh-7 (6HD5, HMK-12), Igh-7a (No. 297) and Igh-7b /JKS-6) were used to qualitate antibodies of the IgE class. The sensitivity of the method is 0.1 ng/ml. Serum IgE levels were much higher in mice infected with Nippostrongylus brasiliensis. In sera of BALB/c, AKR and C3H/JCL mice only IgEa, in sera of C57BL/6 and CB-20 only IgEb, in sera of (BALB/c x C57BL/6) F1 mice, both allotypes were detected, as expected. In mice with autoimmune diseases, such as NZB, NZW, (NZB x NZW) F1, MRL/Ipr and MRL/n strains which all belong to the IgEa allotype group, IgE and IgEa were very high. In the sera of BXSB mice, both IgEa and IgEb were detected. Both IgEa and IgEb from donor and host were increased in the sera of mice with graft-versus-host disease after transplantation but only the IgEa (from the donor) was increased in mice with graft-versus-host disease after bone marrow transplantation. In the former, both B cells (from donor and host) secreted IgE, whereas in the latter only the donor cells did. These are the first observations showing the importance of IgE allotype secretion as an indication of graf-versus-host disease.