The antitumor effects of Corynebacterium parvum in a @entity19 @entity43 model depend upon a sequential activation of neutrophils and macrophages within the peritoneal cavity. We studied the sequential administration of biological response modifiers that independently activate each phase of the response. Tumor-challenged @entity19 treated by i.p. injection of a @entity4605 -extracted fraction of cell-free @entity5478 (PA-PE, 1400 micrograms) demonstrated prolonged survival in less than 20% of the cases. An i.p. injection of a detoxified Salmonella endotoxin (DSE) preparation (150 micrograms) had no effect on @entity5 outgrowth. However, i.p. treatment with PA-PE (1400 micrograms), followed by 150 micrograms of DSE 1 day later, resulted in long-term survival (greater than 100 days) in 40 to 60% of mice. This antitumor effect was only evident when PA-PE was administered first (before DSE) and optimal when DSE was administered 24 h after PA-PE. The synergistic antitumor effect could be duplicated when @entity5 -challenged @entity19 were first treated i.p. with peritoneal polymorphonuclear leukocytes, elicited by injection of PA-PE, and then treated with DSE 18 h later. These data indicate that appropriately timed injection of biological response modifiers with complementary effects can result in a synergistic prevention of @entity5 growth.

Synergistic effects of combination sequential immunotherapies in a @entity19 XXXX model.

@entity43 :: ('MESH:D010051', 'Disease') :: ['ovarian teratocarcinoma'] @entity4605 :: ('MESH:C023666', 'Chemical') :: ['pyridine'] @entity19 :: ('10090', 'Species') :: ['mice', 'murine'] @entity5 :: ('MESH:D009369', 'Disease') :: ['tumor'] @entity5478 :: ('1747', 'Species') :: ['Propionibacterium acnes']
@entity43 :: (MESH:D010051,Disease) :: ['ovarian cancer']
