The alloantibody response in the allogeneically pregnant rat. IV. Analysis of the alloantibody specificities with monoclonal antibodies.

We have compared the serum alloantibody population from female rats immunized either by allogeneic pregnancies or by conventional immunizations. The only allogeneic difference in both types of immunization was class I of the MHC. Pregnancy-induced alloantibodies as compared with conventionally raised alloantibodies were more homogeneous with respect to isoelectric point, and were more homogeneous as defined by competition experiments with anti-class I monoclonal antibodies. The genetic control of the pregnancy-induced alloantibody response was also verified.