Competition for cytotoxic immune capacity against A ‘syngeneic’ mouse tumour distributed at two sites

Abstract

Normal C3H mice will develop fatal ascites after the intraperitoneal injection of as few as 100 BP8 cells. However, mice can be immunized so that they can specifically reject an intraperitoneal challenge of 10(7) of these C3H-derived tumour cells. This paper investigates a phenomenon in which the capacity of immunized mice to reject an intraperitoneal challenge of tumour cells is lost between two to seven days after tumour cells have been given subcutaneously. Investigation of this temporary loss of capacity to reject the intraperitoneal challenge of tumour suggests that this might be due to the attraction of cytotoxic immunity to the site of subcutaneous injection. The possibility that this phenomenon is due to blocking factors, tumour overload, suppressor cells or enhancing antibody has been investigated but experimental results are given which do not favour these explanations.

Tumour-induced changes in murine lymphocyte profiles

“…Lymphocytes capable of lysing tumour targets in vitro can be detected within a week of intradermal injection of tumour cells, but become undetectable after a further 1-2 weeks (Takei et al, 1977). An immunogenic tumour growing in its syngeneic host also generates a concomitant anti-tumour immunity, such that the host can specifically suppress the growth of the same tumour implanted at a distant site (Chassoux et al, 1977). This type of immunity declines as the primary tumour burden increases (Berendt & North, 1980).…”

Analysis of synergy between cyclophosphamide Therapy and Immunity Against a Mouse Tumour

“…There are several the combined effects of anti-tumour im-ways in which synergy between drug munity and cytotoxic drugs (Mihich, treatment Fisher et at., 1975). However, in tumour cells; (2) drugs may actually some instances it has been difficult to potentiate cytotoxic immunity by indistinguish the cytotoxic effect of the terfering with regulatory mechanisms drug on the tumour from the effect of (Askenase et al, 1975;Otterness and Chang, 1976) (Porteous and Munro, 1972;Chassoux et al, 1977 Heparinized Minimum Essential Medium (MEM) was injected i.p. The cell-containing medium was recovered through an abdominal incision with a Pasteur pipette.…”