Comparative Studies of Hageman Factor (Factor XII) in Mammalian Plasmas by Immunological Techniques 1

Abstract

Summary

The HF (factor XII) activity in plasmas of 18 mammalian species has been studied by immunological means and gel filtration. All HFs had the same approximate size as human HF. Primate HF activity was most susceptible to inhibition by antihuman HF serum, ungulate HF activity by antibovine HF serum, and rodent HF activity by anti-rat HF serum. Immunodiffusion studies were consistent with these inhibition studies. These data suggest that mammalian HFs in the same taxonomic order share common antigenic sites.