Electron Microscopic Study of Cell Lines Established from Adult T-Cell Leukemia--Coexistence of Adult T-Cell Leukemia Virus and Epstein-Barr Virus

Six cell lines established from five patients with adult T-cellleukemia (ATL) were studied by electron microscopy. From onepatient two cell lines were established, an interleukin 2-dependentline and a nondependent line. The interleukin 2-dependent T-cellline had only ATL virus (ATLV) particles. The interleukin 2-nondependentB-cell line had both ATLV particles and Epstein-Barr virus (EBV)particles. In two other B-cell lines and one undetermined cellline, both ATLV particles and EBV particies were seen. In oneB-cell line only a few EBV particles were seen. These findingssuggest that (I) interleukin 2 is necessary for the growth ofleukemic T-cells from ATL tissue samples, and (2) ATLV can infectnot only T-cells but also B-cells.