Production of alpha-fetoprotein by cultured rat ascites hepatoma cells determined in vivo as alpha-fetoprotein-negative.

Three ascites hepatoma cells of the rat, AH-41B, AH-34, and AH-64B, which had been determined in vivo as alpha-fetoprotein-negative, were cultivated in vitro in a medium containing adenosine 3',5'-cyclic monophosphate (cyclic AMP), cyclic dibutyryl-AMP, or theophylline. The concentration of alpha-fetoprotein in culture media was measured by the 125 I-radioimmunoassay. Results demonstrated that the AH-41B cells produced alpha-fetoprotein in vitor, the concentration of which being elevated in the media with three substances, while the remaining AH-34 and AH-64B cells did not. A comment was made on the producibility of alpha-fetoprotein in the so-called alpha-fetoprotein-negative hepatoma cells.