The fate of rat tumor cells labeled with sulfanilic-S35 acid in the host.

A method of labeling ra t ascites tumor cells with diazotized sulfanilic-S 35 acid is described. The distr ibution of radioact ivi ty in host ra ts with labeled subcutaneous or ascites tumor implants was studied; radioact ivi ty was found to be present mainly in the tumor, kidneys, spleen, liver, and blood, decreasing in specific act iv i ty in tha t order. In general, the tissue localization of the label derived from the labeled tumor cells in the host ra t resembled the pa t terns observed by Haurowitz et al. (5) following injection of labeled sulfanil-azotyrosine and sulfanil-azoovalbumin and differed from the distribution of free sulfanilic-S 85 acid administered intraperitoneal]y.