Fig. (1).

Myeloid cells in a vicious cycle of HIV associated inflammation. Macrophages, monocytes, DCs and neutrophils play an important role in HIV pathogenesis by various mechanisms leading to generalized inflammation. Myeloid cell up regulation of PD-L1 enhances their interaction with CD4 T cells via PD-1 which further results in CD4 T cell depletion and immune dysfunction. Expression of restriction and/or control factors by these cells is circumvented by HIV. Modulation of production of cytokines and other molecules also contributes to the inflammation.