Detection of HIV1 RNA and p24 antigen in HIV1-infected human liver

To investigate the possibility of HIV1 infection of liver cells, liver samples from 17 infected patients were studied. A monoclonal antibody directed against the p24 gag HIV1 protein was used in an immunoperoxidase assay and yielded positive results in 7/17 samples. Staining by anti-p24 antibody was of three types: diffuse in Kupffer cells of most samples, inside granuloma and in some sinusoidal cells the origin of which was difficult to ascertain. In 5 further liver specimens, HIV1 RNA were identified by in situ hybridization in inflammatory mononuclear cells and/or in scattered sinusoidal cells. Attempts to locate the CD4 membrane antigen showed that it was mainly present on endothelial sinusoidal cells. These results indicate that liver cells, including Kupffer cells, might be infected by HIV1.