A MONOCLONAL-ANTIBODY RAISED AGAINST PIG LEUKOCYTES AND PLATELETS RECOGNIZES FIBRINOGEN FROM PIG PLASMA

Monoclonal antibody (mab) JM7E6 was produced through immunization of m ite with porcine peripheral blood mononuclear cells and platelets, Bio chemical characterization of the antigen showed three bands of 48, 55 and 60 kDa approximately, under reducing condition, and a single band greater than 200 kDa, under non-reducing condition. The antigen distri bution among leukocyte subpopulations was reduced, but abundant in pla telets, which suggests the recognition of a platelet antigen. However, immunohistochemical analysis of paraffin-embedded porcine tissues sho wed reactivity on blood vessel plasma, and indicates recognition of a plasma protein. ELISA and immunoblotting techniques, which were perfor med with commercially available porcine fibrinogen, not only confirmed the identification of this antigen, but also localized the epitope re cognized by JM7E6 in the fibrinogen gamma light chain, JM7E6 failed to recognize human, ovine, bovine and dog fibrinogen molecules, thus sho wing species specificity of the epitope recognized by this antibody, S ince JM7E6 is able to precipitate fibrinogen molecules from porcine le ukocytes and platelets, it may be a valuable tool for some interesting clinical applications.