Rules to activate CD8+T cells through regulating subunits of opioid receptors by methionine enkephalin (MENK)

Abstract

The goal of this work was to investigate how MENK could regulate the functions of CD8⁺T cells and to explore the relationship between this regulation and opioid receptor expression. Our results showed that the opioid receptors presented on the cell menbrane of CD8⁺T cells were MOR and DOR. MENK promoted the expression of opioid receptors as well as the elevation of the surface molecules such as CD28, PD-1, CTLA-4 and FasL and intracellular granzyme B. Selectively blocking the MOR by CTAP or DOR by NTI could result in inhibition of the corresponding CD8⁺T cells proliferation and the expressions of surface molecules. In addition, non-selectively blocking both MOR and DOR by NTX could further impair the functions and proliferation of CD8⁺T cells. Our currently data indicated that MENK could play a vital role in immune functions via precise regulation to subunits of opioid receptors.

Keywords: CD8(+)T cells; CTAP; Methionine enkephalin (MENK); Naltrexone hydrochloride; Naltrindole hydrochloride; Opioid receptor.