JLE

Hématologie

MENU

Role of invariant NKT cells in allogeneic haematopoietic stem cell transplantation Volume 19, issue 2, Mars-Avril 2013

Figures

See all figures

Author
Département d’hématologie et de thérapie cellulaire, hôpital Saint-Antoine, 75012 Paris, CNRS UMR 8147 Hôpital Necker 75014 Paris

The anti-tumor effect (GVT) of allogeneic haematopoëtic stem cell transplantation (HSCT) is often associated to the occurrence of a life threatening graft-versus host disease (GVHD). These immunologic effects are mediated by alloreactive donor T lymphocytes activated by recipient antigens presented by antigen presenting cells stimulated in the inflammatory context observed after graft conditioning. This immune response can be modulated by regulatory T cells; among those invariant NKT lymphocytes have been recently described. This subtype of lymphocyte is characterized by the expression of a semi-invariant TCR, represents < 1% of total peripheral lymphocytes and is endowed with immunoregulatory properties mediated by the production of high amounts of cytokines after their stimulation. Depending on the context of activation and the cytokines produced, they can either induce an immune tolerance or activate anti-tumor and/or infectious responses. In mice, they can inhibit GVHD without impairing GVT. In humans, recent studies suggest their potential implication, in particular for the CD4 - subset, in the regulation of the allogeneic response. These data encourage the development of new immunotherapy strategies in order to better separate the GVH and GVT effects after allogeneic HSCT.