Augmentation of lymphocyte reactivity in guinea pigs, mice, monkeys and humans sensitised to BCG, dinitrochlorobenzene or nitrogen mustard

Abstract

NONSPECIFIC augmentation of tumour immunity has been achieved through the use of Bacillus Calmette-Guérin (BCG), Corynebacterium parvum, Toxoplasma gondii, Besnoitia jellisoni and other intracellular parasites^1–4. Nonliving preparations, such as cell walls from BCG, also cause nonspecific augmentation of tumour immunity⁵. The mechanisms underlying these effects are not clear. It has been postulated that amplification of macrophage or reticuloendothelial function is responsible for the enhancement of tumour immunity by these agents. In the mouse, BCG causes a change in the rate of activation of macrophages, as well as a change in their lysosomal content and bacteriolytic power^6,7. In the guinea pig, there is an initial granulomatous reaction at the BCG inoculation site, followed by a peripheral histocyte-mediated destruction of tumour cells⁸. We have now examined the effect of intradermal BCG on the ‘specific’ and ‘nonspecific’ responsiveness of circulating lymphocytes. We also investigated the ability of two chemical agents to produce similar or additive effects.