Biological Response Modifiers

Abstract

In 1906 Paul Ehrlich observed that when a cancer was transplanted from one animal to another of the same species, it failed to grow, and was apparently destroyed by the new host. This was interpreted as evdence that immune mechanisms could lead to tumour rejection. The animals studied were not, however, genetically similar and thus what Ehrlich had recorded was the general phenomenon of transplant rejection rather than a specific antitumour effect. Despite this setback the possibility of stimulating the host’s own defences to recognise malignant tissue as foreign and bring about its destruction has been vigorously pursued over the years.