Effect of thymectomy on the induction of skin tumours by 3,4-benzopyrene

Inhibition by germ‐free status of development of liver and lung tumours in mice exposed neonatally to 7,12‐dimethylbenz(A)anthracene: Implications in relation to tests for carcinogenicity

“…Previous studies by ourselves and others have shown that neonatal thymectomy renders mice more susceptible to the development of neoplasms in response to chemical agents or oncogenic viruses (Miller et al, 1963;Vandeputte et al, 1963;Malmgren et al, 1964;Kirschstein et a/., 1964;Law, 1965;Nishizuka et al, 19656;Grant et al, 1966). On the other hand, Rigdon et al (1 967), reported that mice receiving neonatal inoculation of rat thymus antiserum (to induce a state of " immunothymectomy or immunothymic blockade ") developed no higher incidence of gastric neoplasms, pulmonary adenomas or lymphomas than mice given saline, or normal serum, in response to benzo(a)pyrene given mixed with the diet.…”

How the thymus shaped immunology and beyond

“…Most importantly, by 180 days 12% of skin tumors in the NTx mice became malignant in contrast to only 4% in the STx mice. 16 My words in the conclusion of the paper are: "Interference with the cellular immune mechanism may be necessary, in some cases, to allow the full expression of a carcinogenic process." 16 7.…”

“…16 My words in the conclusion of the paper are: "Interference with the cellular immune mechanism may be necessary, in some cases, to allow the full expression of a carcinogenic process." 16 7. Some parotid tumors occurred spontaneously in NTx mice that had been given the Gross virus at birth.…”

Antigen‐specific clone selection in vivo

“…3 He was, at that time, one of the few immunologists convinced of the immune function of the thymus, as was evident in the lecture he later gave in London. 4 The finding that thymus-deficient mice were much more prone than normal mice to develop tumours after treatment with certain carcinogenic chemical agents and oncogenic viruses 5,6 provided some experimental support for Burnet's concept of immunological surveillance. 7 Although T cells can, in some experimental situations, act as killer cells against tumour cells, I believe that if tumour antigens do cross-react with self-antigens that are ectopically expressed in thymus medullary epithelial cells, one will not be able to prime the immune system to these antigens.…”