A rapid method for obtaining specific antibodies to mouse alpha 1-fetoprotein.

Rabbit antiserum to whole mouse amniotic fluid can be made alpha 1-fetoprotein-specific by in vivo absorption into adult mice. The technique is easy to perform, with minimum training, and provides an average of 0.8-1.2 ml of specific antiserum in an absorption time of 5 min. The unfractionated absorbed antiserum, when precipitated with glutaraldehyde, can be used as an immunoabsorbent to purify alpha 1-fetoprotein from whole amniotic fluid, yielding an average of 100 microgram of alpha 1-fetoprotein/ml of immunoabsorbent. The isolated protein appears antigenically pure when analyzed by SDS-PAGE.