Leukocytic subset distributions of spleen cells obtained from rats bearing variants of the Dunning prostatic adenocarcinoma.

Employing monoclonal antibodies, the relative frequencies of mononuclear cell types found in spleen cell populations were compared between rats bearing variants of the Dunning prostate adenocarcinoma and a series of non-tumor bearing control animals. The identification and quantitation of such subsets greatly expands our knowledge of immune status and function. The results indicate that the spleen cell populations from animals bearing either the Dunning R3327-H, G or MAT-LyLu sublines have significant decreases in their helper T cell/suppressor T cell ratios when comparisons are made to cells obtained from non-tumor bearing animals. In addition decreases in total T cell content and increases in splenic monocytes were noted. It appears that most of these deviations are the result of general Dunning tumor presence, rather than due to any particular subline characteristic. These changes may be analogous to similar alterations reported in the peripheral blood of humans bearing Stage D prostatic cancer, suggesting that the Dunning tumor may provide an appropriate model for evaluating interactions between the immune response, the tumor and therapy.