Abstract
A cytotoxic factor (CF) toward cultured murine leukemia L1210 cells was induced in mouse serum by intravenous injection of a dehydrogenation polymer of p-coumaric acid (DHP-pCA). When the serum from the treated mice was diluted with ethanol, CF was preserved in its supernatant (EtOH-sup). An EtOH-sup prepared from untreated control mice also showed cytotoxicity, although at much higher concentrations. The CF activity of EtOH-sups from both treated and untreated mice was completely eliminated by acid treatment at pH 2 at 90°C for 30 min but kept intact by alkali treatment. In addition, the CF activity of both EtOH-sups was not affected by digestion with chymotrypsin. CF was recovered in a neutral MeOH-eluate from a DEAE-cellulofine column but not in HCl-MeOH eluate, in which lignified materials including DHP-pCA should have been recovered. These findings strongly suggest that CF is not a metabolite of DHP-pCA but an endogenous component of the normal serum which is augmented by DHP-pCA administration.
