Immunoglobulin M antiplatelet autoantibodies from mice immunized with rat platelets induce thrombocytopenia and platelet function impairment.
Antiplatelet monoclonal autoantibodies (mAbs) were derived from CBA mice immunized with rat platelets. Two IgM antiplatelet mAbs were further analyzed. L1C43 mAb bound a 150-160 kDa antigen, recognized activated platelets better than resting ones and impaired platelet adhesion, but not clot retraction. L1H31 mAb recognized a ±95 kDa molecule, bound similarly activated and resting platelets and did not modify platelet adhesion, but inhibited clot retraction. Both mAbs induced in vivo thrombocytopenia most likely through phagocytosis of opsonized platelets. These autoreactive antibodies can thus induce both platelet destruction and impairment of their function. They are reflective of autoantibodies found in human patients and may serve for further analysis of antiplatelet autoantibody pathogenicity and mechanisms of autoimmune disease.
The Unit of Experimental Medicine, Christian de Duve Institute, Université catholique de Louvain, Avenue Hippocrate 74, 1200 Brussels, Belgium.
Laurent
L
Detalle
Dan
D
Su
Nico
N
van Rooijen
Jean-Paul
JP
Coutelier
D000818:Animals; D000911:Antibodies, Monoclonal / Q000096:biosynthesis / Q000302:isolation & purification / Q000633:toxicity*; D001323:Autoantibodies / Q000096:biosynthesis / Q000302:isolation & purification*; D001792:Blood Platelets / Q000187:drug effects / Q000276:immunology* / Q000378:metabolism; D004797:Enzyme-Linked Immunosorbent Assay; D007114:Immunization; D007075:Immunoglobulin M / Q000096:biosynthesis / Q000633:toxicity*; D051379:Mice; D008808:Mice, Inbred CBA; D009895:Opsonin Proteins / Q000378:metabolism; D010587:Phagocytosis / Q000187:drug effects; D010976:Platelet Count; D051381:Rats; D011919:Rats, Inbred Strains; D017208:Rats, Wistar; D013921:Thrombocytopenia / Q000139:chemically induced / Q000276:immunology*
D000911:Antibodies, Monoclonal; D001323:Autoantibodies; D007075:Immunoglobulin M; D009895:Opsonin Proteins