Experimental models for antiphospholipid studies.

Three types of Experimental Animal Models have been used to investigate APA. 1) Passive transfer of APA to nocive mice. Branch et al injected pregnant Balb/c mice with purified IgG APA from patients with recurrent fetal loss. 2) Active immunization with APA. Backimer et al immunized Balb/c mice with a human monoclonal APA carrying the pathogenic idiotypes. 3) Immunization with beta 2 glycoprotein I (beta 2 GPI) (APA cofactor). Using affinity chromatography, we separated two distinct populations of antibodies. One was specific for beta 2GPI without binding to PL. Another population had a dual specificity for PL and beta 2GPI.