Guilty by Association
Menée à l'aide de modèles murins, cette étude met en évidence une population endogène de lymphocytes Treg spécifiques ayant infiltré les tumeurs de la prostate en développement
Developing tumors face a multifaceted immune response that can ultimately "edit" the tumor by eliminating cells that cannot evade antitumor responses. Consequentially, tumors employ many mechanisms to evade immune responses, including expression of inhibitory chemokines or cytokines and recruitment of immunosuppressive cells such as regulatory T cells (Tregs) (1, 2). Tregs are known for suppressing immune responses and maintaining immune homeostasis, but are also often found in the tumor microenvironment where their presence correlates with poorer patient outcomes. Moreover, acute Treg depletion in transplant models of cancer results in more potent antitumor immune responses. Thus, Tregs are considered important players in tumor development. However, relatively little is known about why Tregs infiltrate tumors or how they are formed. On page 1219 of this issue, Malchow et al. (3) address these questions and discover that developing tumors do not elicit novel Treg responses, but rather they recruit and/or expand Treg populations naturally found within the tissue from which the tumor arises.
Science , commentaire, 2013