A radioimmunoassay for mouse alpha-lactalbumin.

alpha-Lactalbumin has been purified from mouse milk by the use of ammonium sulfate precipitation, Bio-Gel P-100 chromatography and DEAE-cellulose chromatography. Mouse alpha-lactalbumin exists as two major charge forms with the same molecular weight. Both charge forms have been used in the development of a radioimmunoassay to mouse alpha-lactalbumin. The assay is specific for mouse alpha-lactalbumin, reacting identically with both forms, and sensitive with a minimal detectable concentration of 0.35 ng. alpha-Lactalbumin induced in mouse mammary gland explants has been measured with the use of the radioimmunoassay and is detectable in both the explants and media of the cultures.