Immunological characterization of type-D retrovirus isolates from human cells

Competition radioimmunoassays for the 27,000 molecular weight(p27) major internal protein and the low-molecular-weight 10,000-12,000 (p10-12) polypeptides of the primate type-D retroviruses, Mason-Pfizer virus(MPV) and langur virus (LV), were established. Type-D isolates from various primate and human tumor cells were examined in both these assays. There were no detectable immunological differences between MPV and two type-D retroviruses previously reported to be isolated from human cell lines (HeLa and AO). Type-D retroviruses isolated from human T9 and J96 cells (cell lines derived from human leukemic cells), however, were clearly distinguishable from both MPV and LV in their respective p10-12 radioimmunoassays. These assays thus demonstrate that type-D retroviruses isolated from some human cells may differ immunologically from morphologically similar viruses isolated from nonhuman primates.