Улога регулаторних Т лимфоцита у модулацији имунског одговора на малигне ћелије

Abstract

Regulatory T cells (Treg) represent a subset of CD4⁺T cells whose function is to suppress immune responses. Treg lymphocytes can be divided into two subsets: natural nTreg lymphocytes that are developed in the thymus and inducible iTreg lymphocytes, which originate from conventional T lymphocytes on the periphery. The majority of Treg lymphocytes express high levels of interleukin-2 (IL-2) receptor α chain (CD25) and transcription factor FoxP3 (critical for the development and suppressor activity of iTreg lymphocytes). Cancer cells can modulate anti-tumor immune response indirectly, through the activation of Treg lymphocytes. It has been shown that the loss of regulatory function by depletion of tumor-induced Treg lymphocytes may enhance effectors response, resulting in tumor rejection, while the increased number of Treg lymphocytes effectively prevents tumor destruction. nTreg lymphocytes express increasingly CTLA-4 and membrane-bound TGF-β, which inhibits cytokine production and responses of effectors lymphocytes. iTreg lymphocytes secrete immunosuppressive cytokines such as IL-10 and TGF-β. Treg lymphocytes represent one of important obstruction in anti-tumor immunity.

Keywords: regulatory T cells; tumors; anti-tumor immune response