[Electron microscopic observation of ATLV (adult T-cell leukemia associated virus)]

The morphological structure and morphogenesis of ATLV produced from MT-1, MT-2 cell lines and short-term cultured cells from peripheral lymphocytes of ATL patients were observed by electronmicroscopy. The average diameter of ATLV particles was approximately 110 nm, and the distribution curve of diameter was wide. The ATLV was produced by budding process but budding was very rare. Most of the ATLV was mature type C-virus particle and immature particle could not be detected. It was observed by indirect immunoelectron microscopy that some human sera with high anti-ATLA titers reacted with both the ATLV and the cell membrane surface of MT-2 cells. From these results, it is suggested that the ATLV is new type C particle which has the antigenicity against the anti-ATLA positive sera.