Ribosome-lamella complexes observed in an Epstein-Barr virus-producing B-cell line, infected with human...

Co-cultivation of peripheral blood mononuclear cells, from a 4-year-old boy with infectious mononucleosis, with a human T lymphotrophic virus type I (HTLV-I)-producing T-cell line resulted in the establishment of an HTLV-I infected Epstein-Barr virus (EBV)-producing B-cell line. Ultrastructural examination revealed the presence of ribosome-lamella complexes (RLCs), in a small proportion of long-term cultured cells. Evidence is presented of continuity between RLC and the rough endoplasmic reticulum, and in some instances there was also an intimate relationship with tubuloreticular structures. The findings support the view that RLC is derived from the rough endoplasmic reticulum and also provide further evidence of the non-specific nature of RLC in relation to cell type.