Importantly, our studies of chemokine induction in monocytes from HIV+ donors represent only a small number of subjects and we have only anecdotally examined responses in viraemic and aviraemic subjects. From our previous studies of CD80 induction Dorsomorphin cell line by hBD-3, viraemia does not seem to play a major role in diminished hBD-3 responsiveness; however, this may depend on the functional read-out being investigated.
Assessment of monocyte responses to antimicrobial peptide-mediated stimulation and discernment of the mechanism(s) responsible for monocyte dysfunction may provide new insights into immune deficiencies in HIV-infected persons, including those persons receiving anti-retroviral therapy. This work was supported by a National Institutes of Health grant (DE17335), by the Center for AIDS Research at Case this website Western Reserve University (AI-36219) and by a grant from the James B. Pendleton Charitable Trust. The authors have no competing interests. “
“M.tb is an intracellular pathogen which survives within the phagosomes
of host macrophages by inhibiting their fusion with lysosomes. Here, it has been demonstrated that a lysosomal glycoprotein, CD63, is recruited to the majority of M.tb phagosomes, while RILP shows limited localization. This is consistent with the author’s findings that CD63, but not RILP, is recruited to the phagosomes in macrophages expressing Paclitaxel purchase the dominant negative form of Rab7. These results suggest that M.tb phagosomes
selectively fuse with endosomes and lysosomes to escape killing activity while acquiring nutrients. Phagocytosis of infected pathogens by macrophages plays an important role in the early stages of innate immunity. Phagocytosed pathogens are incorporated into phagosomal vacuoles. These phagosomes then interact with endosomal and lysosomal vesicles in a process referred to as phagolysosome biogenesis. During phagolysosome biogenesis, phagosomes acquire degradative and microbicidal properties, leading phagocytosed pathogens to be killed and degraded. M.tb, the causative bacterium of tuberculosis, infects more than one-third of the human population. M.tb is able to survive and proliferate within phagosomes of the host’s macrophages by inhibiting phagolysosome biogenesis (1, 2). However, the exact process by which M.tb blocks phagolysosome biogenesis is not fully understood. Recently, it was reported that phagosomes containing M.tb (M.tb phagosomes) within dendritic cells are associated with lysosomes in the early stages of infection (3). In addition, we have previously demonstrated that LAMP-2, but not cathepsin D, is recruited to M.tb phagosomes in macrophages (4). These results suggest that M.tb phagosomes selectively fuse with lysosomal vesicles which have distinct characteristics.