Monoclonal autoantibodies with interleukin 3-like activity derived from a MRL/lpr mouse.
Hybridomas that secrete monoclonal antibodies with interleukin 3 (IL-3)-like activity were established from spleen cells of a nonimmunized autoimmune MRL/lpr mouse. Five of the monoclonal antibodies thus obtained bound selectively to IL-3-dependent cells and supported their growth. These monoclonal antibodies inhibited the binding of IL-3 to FDC-P2 cells and vice versa. Thus, these antibodies were probably directed to IL-3 receptor sites, or at least to some cell surface proteins related to the growth of the IL-3-dependent cells. These MRL/lpr-derived monoclonal antibodies reacted strongly with cells from bone marrow, spleen, and lymph node of MRL/lpr mice, but minimally with such cells of MRL/+ or BALB/c mice. The findings were consistent with our earlier suggestion that the IL-3-like activity in MRL/lpr sera is not caused by IL-3 itself but is associated with IgG that is probably an autoantibody directed to the IL-3 receptor.
D000818:Animals; D000911:Antibodies, Monoclonal / Q000502:physiology*; D000937:Antigen-Antibody Reactions; D000941:Antigens / Q000276:immunology; D001323:Autoantibodies / Q000502:physiology*; D001666:Binding Sites, Antibody; D001667:Binding, Competitive; D002460:Cell Line; D005260:Female; D007202:Indicators and Reagents; D007377:Interleukin-3 / Q000276:immunology* / Q000502:physiology; D051379:Mice; D008815:Mice, Inbred Strains / Q000276:immunology*; D013194:Staining and Labeling; D014018:Tissue Distribution
D000911:Antibodies, Monoclonal; D000941:Antigens; D001323:Autoantibodies; D007202:Indicators and Reagents; D007377:Interleukin-3