Cooperative interactions between neurotrophin receptors and CXCR4 regulate macrophage phenotype and susceptibility to activation by HIV.

Neural damage due to inflammatory activation of macrophages and microglia is a consequence of HIV infection that leads to cognitive dysfunction. The damage is due, in part, to the release of factors that impair neuronal function but the mechanisms that control their release are poorly understood. Previous studies have shown that mature nerve growth factor (NGF) binding to tropomyosin receptor kinase A (TrkA), and proNGF acting through the p75 neurotrophin receptor (p75) differentially control the phenotype of macrophages in response to HIV.