Purification of mouse alpha1-fetoprotein and preparation of specific peroxidase conjugates for its cellular localization.

Mouse alpha1-fetoprotein (AFP) was isolated from amniotic fluid by immunoadsorbent columns and preparative electrophoresis. Specific antibodies were isolated from monospecific hyperimmunsera by use of immunoadsorbents, and subsequently coupled with horseradish peroxidase. At the light microscopical level, purified antibody-peroxidase conjugates were used for the cellular localization of AFP in fetal liver by direct and indirect staining methods. Fixatives containing ethanol or aldehydes were tried for antigen staining. Prior to immunocytological reactions, endogenous peroxidases were inhibited by hydrogen peroxide.