Immunologic and hematologic properties of antibodies to prothrombin and plasminogen in a mouse model.
Antibodies to prothrombin have been associated with venous and arterial thrombosis, and they cross-react with a structurally closely related protein plasminogen. We immunised 16 mice with human prothrombin and 15 mice with human plasminogen. Mice immunised with prothrombin developed cross-reactive antibodies to plasminogen (12/16), beta2-glycoprotein I (4/16), tissue-type plasminogen activator (6/16) and cardiolipin (11/16). Mice immunised with plasminogen developed cross-reactive antibodies to prothrombin (8/15), tissue-type plasminogen activator (2/12) and cardiolipin (5/12). Functional effects of antibodies were examined. Immunisation with prothrombin induced lupus anticoagulant activity in 9/14 mice. In mice immunised with plasminogen, radial fibrinolysis was inhibited in 8/10 and plasminogen activation in the chromogenic assay was inhibited in 9/11. No cross-functionality was observed. In conclusion, antibodies to prothrombin and plasminogen cross-react in vivo. Antibodies to prothrombin and plasminogen have different functional profiles, immunisation with prothrombin leads to prolonged blood clotting time, and immunisation with plasminogen induces antibodies interfering with fibrinolysis.
Puurunen
M
M
Department of Health and Disability, National Public Health Institute, Helsinki, Finland. marja.puurunen@phks.fi
Palosuo
T
T
Lassila
R
R
Anttila
M
M
Vaarala
O
O
D000818:Animals; D000906:Antibodies / Q000276:immunology*; D000918:Antibody Specificity; D001777:Blood Coagulation; D006801:Humans; D051379:Mice; D008807:Mice, Inbred BALB C; D008810:Mice, Inbred C57BL; D010958:Plasminogen / Q000276:immunology*; D011516:Prothrombin / Q000276:immunology*
D000906:Antibodies; D011516:Prothrombin; D010958:Plasminogen