Quantitative study of the effect of previous Trichinella spiralis infection on sarcoma 180 ascitic tumor formation in mice.

Tumor development in HaM/ICR mice inoculated intraperitoneally with Sarcoma 180 (S-180) can be easily quantitated by linear regression analysis of non-destructive measurement of total body mass. This procedure readily separated the postinoculation period into incubation and clinical phases. The former was dependent on S-180 dose, while the latter was not. Trichinella spiralis infection 28 days prior to S-180 challenge produced small but statistically significant increases in the length of both the incubation period and survival time, but did not affect the clinical phase. Administration of tumor cells 56 days followoing the helminthic infection had no detectable effect on any parameter of tumor development studied. The results are consistent with the hypothesis that T. spiralis infection temporarily altered the host reaction to S-180, possibly at the level of non-specific macrophage activity.