The immune microenvironment of human tumors is highly complex and is composed of all populations of lymphoïd and myeloblastic cells. The immune contexture, which takes into account the density, location and functional orientation of immune cells, is a major prognostic factor for patient's survival. In most cancers, a strong infiltration of memory CD8 T cells and a Th1 correlates with longer survival of patients with primary or metastatic cancer. Howewer, the expression of immune check-point molecules, such as PD-1, LAG3, TIM3 on lymphocytes and of their ligands on tumor cells or myeloid cells greatly affect the progostic impact of the anti-tumor immune response. Tertiary Lymphoid Structures, similar to those found in auto-immune inflammed sites, are essential sites for shaping effective, or exhausted, anti-tumor immune reactions.The immune contexture,its buiding and its modulation will be discussed in the light of the exploding use of immune check point modulators in cancer, with consequences on auto-immune and inflammatory diseases.
Disclosure of Interest W. Fridman Consultant for: SERVIER, LFB, SANOFI, PIERRE FABRE MEDICAMENT