Inhibition or acceleration of fibrin polymerization by monoclonal immunoglobulins and immunoglobulin fragments.
A prolongation of the thrombin clotting time by at least 25% was found in the presence of 8 of 26 IgG myeloma proteins, 2 of 5 IgA proteins and 1 of 10 macroglobulins, in a concentration of 10 mg/ml. Normal pooled immunoglobulin in concentrations up to 83 mg/ml were inactive. 2 IgG and 2 IgM monoclonal immunoglobulins caused an acceleration of the thrombin time by at least 20%; this phenomenon has not been reported before. Corresponding results were obtained with these proteins when the polymerization of des-AA and des-AABB fibrin monomers were investigated in a light scattering system. Studies with enzymatically produced Fab, F(ab')2 and Fc fragments from normal and monoclonal immunoglobulin suggested that the polymerization inhibitory activity resides in the Fab portion of the immunoglobulin molecule. While the ability to inhibit fibrin polymerization may be an immunoglobulin specific effect, the acceleration caused by certain other monoclonal immunoglobulins may be an unspecific effect similar to that seen with dextran or albumin.
D000818:Animals; D000911:Antibodies, Monoclonal; D002417:Cattle; D005338:Fibrin Fibrinogen Degradation Products / Q000378:metabolism*; D007128:Immunoglobulin Fragments / Q000378:metabolism*; D007136:Immunoglobulins / Q000378:metabolism*; D008027:Light; D009194:Myeloma Proteins / Q000378:metabolism; D011108:Polymers / Q000378:metabolism; D012542:Scattering, Radiation; D013918:Thrombin Time
D000911:Antibodies, Monoclonal; D005338:Fibrin Fibrinogen Degradation Products; D007128:Immunoglobulin Fragments; D007136:Immunoglobulins; D009194:Myeloma Proteins; D011108:Polymers; C011468:fibrinmonomer; C017551:myeloma immunoglobulins