Hybridoma autoantibodies to erythrocytes from NZB mice and the induction of hemolytic anemia.

We established two clones of monoclonal hybridoma, from a non-immunized NZB mouse, which produce IgM class hemagglutinating autoantibodies reactive with the exposed murine erythrocyte autoantigens. Absorption studies revealed that one monoclonal antibody exhibits cross-reactivity to chick erythrocytes and mouse liver, and the other antibody to rat erythrocytes and mouse brain. Optimal temperatures for the hemagglutination were 22 degrees C with the former and 4 degrees C with the latter. The specificity and nature of the autoantibodies are apparently distinct from any of the erythrocyte autoantibodies described to date in NZB mice, anti-X, anti-HB, anti-HOL or anti-I antibodies. Implantation of these hybridoma cells in BALB/c mice induced autoimmune hemolytic anemia associated with a marked splenomegaly. These findings provide evidence that the erythrocyte autoantibodies in NZB mice are more heterogenous than generally assumed and suggest that varieties of erythrocyte autoantibodies may be involved in the development of a naturally occurring hemolytic disease in NZB mice.