[A case of chronic B cell lymphocytic leukemia with expression of CD8 antigen on leukemic cells].

CD8 antigen is present on the surface of cytotoxic-suppressor T cells, NK cells and majority of thymocytes. Expression of CD 8 is associated with CD 3 antigen, which is a part of a T cell receptor. However, CD 8 antigen is undetectable on normal B cells. In sporadic cases of B cell-chronic lymphocytic leukaemia (B-CLL) it was found on leukaemic B cells. We report a case of B-CLL of benign course with CD19+, CD5+, CD40+, CD19+, CD20+, CD19+, CD19+HLADR+ leukaemic cells expressing CD8 antigen on CD19+ leukaemic cells. It seems that original neoplasms source was localized out of bone marrow. We suggest that the origin of the target cell for neoplasms transformation could be CD5+ B cell and CD8+ T cell gamma + delta + CD8+.