Muriel MOSER, Ph.D
Oberdan LEO, PhD
Fabienne ANDRIS, PhD
Guillaume OLDENHOVE, PhD
There is strong evidence that the immune system can recognize tumour-associated antigens and reject established malignancies in vivo. However, ongoing studies show that induction of effector mechanisms is not sufficient to induce tumour rejection in vivo, and that strategies aimed at circumventing the negative regulatory loops that appear to dampen anti-tumour responses will be required to achieve optimal protection in cancer immunotherapy.
We are presently exploring some fundamental aspects of the anti-tumour responses in vivo, with the aim of identifying the suppressor mechanism(s) counteracting tumour resistance. Our observations suggest that the regulatory cells inhibiting anti-tumour responses represent a heterogeneous set of cells, including naturally and induced regulatory T cells and a subpopulation of cells of the innate immune system including myeloid suppressor cells. In addition, we are trying to identify the effector cells able to eradicate the P815 mastocytoma in vivo. Our results underline the major role of both CD4+ and CD8+ T cells. Their localization, specificity and function are presently under investigation.