Heterogeneity of macrophage and T cell subpopulations in peripheral nerves from HIV infected individuals: A preliminary study

Goal: To determine the heterogeneity of surface marker expression of macrophages in peripheral nerve of patients who died with AIDS. Background: Peripheral neuropathy occurs in 20%-40% of AIDS patients. There is evidence that activated macrophages may be involved in the neural damage associated with HIV-1 infection. We studied the expression of macrophage surface markers CD14, CD11c, CD68, and HLA-DR and also T cell surface markers CD3, CD4, and CD8 in peripheral nerves of AIDS patients. Methods: Three levels of peripheral nerves (sciatic, tibial, or sural) were examined from a limited number of subjects consisting of 4 HIV-seropositive and 5 HIV-seronegative individuals. Standard immunohistochemical technique utilized alkaline phosphatase conjugate and fuchsin substrate. Results: Surface antigen expression was significantly (p < .0025) increased in HIV-positive tissues compared with HIV-negative controls for CD14 and CD4 in sciatic nerves, CD68 and CD4 in tibial nerves, and CD68 in sural nerves. There were trends for increased expression of HLA-DR, CD3, and CD8 in sciatic nerves, CD11c and CD14 in tibial nerves, and CD14, HLA-DR, and CD4 in sural nerves in HIV- positive tissues compared with HIV-negative controls. Conclusion: During the course of AIDS there may be an involvement of all three levels of peripheral nerves suggesting that HIV-related neuropathy is a multifocal process.