Complexes of Protein-Free Lipid Thromboplastin and Prothrombin Conversion Factors

Abstract
Protein-free lipid thromboplastin undergoes the cothromboplastin reaction to form the same 3 types of complexes as form with tissue protein thromboplastin, namely, (1) thromboplastin + Ca + stable factor, (2) thromboplastin + labile factor, and (3) thromboplastin + Ca + stable factor + labile factor. The first 2, incomplete complexes are inactive individually or in mixtures. The 3d, a complete complex, exceeds in thromboplastin activity the most active preparation from tissue protein.