Presence of alpha-naphthyl acetate esterase activity in human haematopoietic cell lines and in fresh biopsy specimens of lymphoma and myeloma.

We have previously shown that non-proliferating human T- but not B-lymphocytes contain demonstrable amounts of acid alpha-naphthyl acetate esterase (ANAE). The usefulness of this histochemical marker for the diagnosis and classification of malignant lymphoid tumors was investigated by use of a panel of established normal and malignant human haematopoietic cell lines and fresh biopsy cells from malignant lymphomas and myelomas. The results showed that not only the T-cell derived acute leukaemia lines, but also histiocytic lymphoma and myeloma lines and some of the lymphoma (Burkitt and lymphocytic) and non-neoplastic lymphoblastoid cell lines with B-cell surface markers expressed strong ANAE reactivity. Some but not all of the immunoglobulin producing myeloma and lymphocytic lymphoma biopsies were ANAE-positive. Inhibition experiments with sodium fluoride and E-600 demonstrated that although the T-lymphocyte specific esterase is predominantly of 'A'-type, the malignant lines contain also non-specific 'B' esterase and pseudocholinesterase. As the presence of the various esterases did not demonstrate any specific distribution pattern among he haematopoietic cell lines of different origin, we concluded that the ANAE marker is no longer T-specific when malignant lymphoid cells are considered, and that the usefulness of this marker in routine diagnostic work therefore is limited.