The effect of chemically induced oral carcinomas on peritoneal macrophages.

Peritoneal macrophages derived from normal and 7,12-dimethylbenz(a) anthracene (DMBA) treated, tumor bearing, Syrian hamsters were isolated and characterized. Peritoneal exudate cells from tumor bearing animals as compared to normal controls, showed that there was an increase in the total number of cells in the exudate. Specifically, there was an increase in macrophages as compared to other cell types. In terms of their cytochemical functions, these macrophages demonstrated a reduction in histochemical activity and functional capacity (Fc and C3 receptors), and cytotoxic specific lysis of DMBA squamous cell carcinoma tumor targets. There was also a significant increase in adherence and the number of resident macrophages as opposed to exudate macrophages of the peritoneal macrophages. These results seem to indicate an alteration in functional and cytochemical activity of macrophages derived from a hamster with a growing cheek pouch tumor induced by DMBA.