A biological assay for epidermal growth factor/urogastrone and related polypeptides.

A bioassay for epidermal growth factor (EFG) which is rapid, specific, and extremely sensitive is described. As the bioassay detects as little as 25 pg of EGF, this assay is more sensitive than commonly used radioreceptor assays and nearly as sensitive as radioimmunoassays. This bioassay involves only the measurement of the proliferation of cultures of an EGF-requiring cell line and can be carried out in a quantitative manner over a 40-fold range of EGF concentrations.