Effect of chronic morphine administration on circulating dendritic cells in SIV-infected rhesus macaques

We studied the effect of chronic morphine administration on the circulating dendritic cell population dynamics associated with SW infection using rhesus macaques. Animals were either first infected with SIV and then given chronic morphine, or visa versa. SW infection increased the numbers of myeloid DCs (mDCs), but morphine treatment attenuated this mDC expansion. In contrast, morphine increased the numbers of plasmacytoid DCs (pDCs) in SW-infected animals. Finally, chronic morphine administration (no SW) transiently increased the numbers of circulating pDCs. These results show that chronic morphine induces a significant alteration in the available circulating levels of critical antigen-presenting cells. (C) 2016 Elsevier B.V. All rights reserved.