Radioimmunoassay of ovine alpha-fetoprotein

Highly purified ovine alpha-fetoprotein (AFP) was used both for radioisotope labelling and as the reference standard in the double antibody radioimmunoassay of ovine AFP. The sensitivity of the assay is 2 ng/ml which is about 8000 times more sensitive than radialimmunodiffusion assay. The assay is of sufficient sensitivity to quantitate AFP in normal adult sheep serum, pregnancy serum, amniotic fluid and fetal lamb serum.