A potential complication of intraperitoneal neoplasms is the occurance of peritoneal metastases. This experiment hypothesizes that resident peritoneal macrophages, activated by muramyl tripeptide (MTP-PE), will destroy peritoneal tumor. MTP-PE is a lipophilic derivative of the myocbacteria cell wall component responsible for induction of cellular immunity and activation of macrophages to a tumoricidal state. A transplantable murine fibrosarcoma, MCA-F was utilized. Murine hosts were challenged intraperitoneally with 5×103 MCA-F cells. Treatment with MTP-PE micelles or liposome-encapsulated MTP-PE was initiated 48 hours prechallenge and on the day of tumor challenge and continued at 72 hour intervals for the subsequent 21 days. Hosts were observed for survival. At 45 days after tumor challenge, all untreated control animals had succumbed to overwhelming neoplastic disease. In contrast, 30% of the mice treated with liposome-encapsulated MTP-PE (P<.05) and 50% of the animals treated with MTP-PE micelles (P<.001) remained alive at 60 days. Followed for 120 days, 20% of MTP-PE micelle treated mice are long-term survivors. These results suggest that control of intraperitoneal seedings may be achieved with MTP-PE when the tumor burden is small.
All Science Journal Classification (ASJC) codes
- Pediatrics, Perinatology, and Child Health