Developmental expression patterns of CCR5 and CXCR4 in the rhesus macaque brain

Emerging data indicate that chemokine receptors on neurons and glia in the central nervous system (CNS) play a role in normal CNS development, intercellular communication, and the neuropathogenesis of AIDS. To further understand chemokine receptors in the brain and explore their potential role in HIV neuropathogenesis, particularly in pediatrics, we examined the regional and cellular distribution of CCR5 and CXCR4 in normal fetal, neonatal, and adult rhesus macaques. CCR5 and CXCR4 were detected by immunohistochemistry and immunofluorescence within the cytoplasm of subpopulations of neurons in the neocortex, hippocampus, basal nuclei, thalamus, brain stem, and cerebellum and by flow cytometry on the surface of neurons and glia. Interestingly, expression of CCR5 and CXCR4 increased significantly (p<0.05) from birth to 9 months of age. We further characterize this dynamic developmental pattern of CCR5 and CXCR4 expression in resident cells of the CNS.