In vitro antitumor effect of lymphoid cells from Corynebacterium parvum-treated mice: effect of route of C. parvum administration.

Corynebacterium parvum administration in CBA mice resulted in the stimulation in the peritoneal exudate and other lymphoid organs of cells which nonspecifically inhibited the tumor growth in vitro. The distribution of the antitumor activity in different organs was dependent on the route of C. parvum injection. Both ip and iv treatments stimulated antitumor activity in the peritoneal exudate, whereas the sc route was ineffective. Only iv treatment stimulated the antitumor activity in the blood, and only the sc route produced the antitumor activity in the lymph node. The antitumor activity following the sc treatment was confined mainly to nodes draining the site of C. parvum injection. All routes of treatment provoked some antitumor activity in the spleen, although the degree of the activity varied with the route in the order of ip, iv, and sc. The antitumor activity in all organs peaked between 4 and 14 days after C. parvum injection. This activity in all organs, except the spleen, disappeared by day 42 post treatment. The results are discussed in the light of the in vivo observations on the antitumor effects of C. parvum.