Primary cultures from a brain biopsy specimen of a human T-cell lymphotropic virus type III/lymphadenopathy-associated virus (HTLV-III/LAV) seropositive patient with progressive dementia contained small numbers of monocytoid cells and showed reverse transcriptase activity that persisted for as long as 100 days. Electron microscopy of these cells revealed the presence of HTLV-III/LAV virions. Subcultured cells removed from primary cultures by trypsinization were nonspecific esterase negative and did not express virus or show evidence of HTLV-III/LAV proviral sequences, while those remaining in the original flasks were nonspecific esterase positive and continued to produce virus.
View Article and Find Full Text PDFCells with properties characteristic of mononuclear phagocytes were evaluated for infectivity with five different isolates of the AIDS virus, HTLV-III/LAV. Mononuclear phagocytes cultured from brain and lung tissues of AIDS patients harbored the virus. In vitro-infected macrophages from the peripheral blood, bone marrow, or cord blood of healthy donors produced large quantities of virus.
View Article and Find Full Text PDFMouse glial and neuroblastoma cells were infected with the mouse adapted strains C506 and 139A of scrapie agent. Lysates of the in vitro infected cells (from the 3rd to the 16th passage) intracerebrally inoculated into CD-1 mice, caused the development of a neurological disease, with characteristic signs of scrapie. Morphological changes in scrapie-infected neural cells were observed after about fifteen in vitro passages.
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