Local and systemic effects in the non-specific tumour resistance induced by attenuated Salmonella enteritidis 11RX in mice.

Suppression of growth of a number of different murine tumours, injected subcutaneously or into the foot pad, was induced by prior intraperitoneal or intravenous immunisation with Salmonella enteritidis 11RX. The effect of immunisation on tumour growth was relatively minor, but could be enhanced by addition of 11RX antigen preparations to the suspensions of tumour cells used for challenge. The significance of these findings is discussed.