Abstract
Acid α-naphthyl acetate esterase (ANAE) activity has been found to be a useful enzymocytochemical marker for T lymphocytes in human peripheral blood and lymphoid organs. ANAE staining was carried out in cells from blood smears and tissue sections (lymph node, skin) of various malignant lymphomas. The results were summarized as follows.
1) ANAE staining patterns: The majority of T cells separated by E-rosetting, showed a localized, intense brownish reaction product (T pattern). Some T cells expressed faint, diffuse reaction product (T′ pattern). Monocytes showed diffuse cytoplasmic ANAE activity (M pattern). Most B cells and granulocytes were ANAE negative.
2) T and B cell type in malignant lymphomas: All nodular lymphomas (2 cases) were proved to be of as B cell origin. Of 12 diffuse lymphomas, 11 were T, and 1 was “null” type. One case of Hodgkin’s lymphoma was T cell type.
A high percentage of ANAE-positive lymphoid cells was found in most of the malignant cutaneous lymphomas, including Sézary’s syndrome and mycosis fungoides. Only one case was B cell type. The histochemical demonstration of ANAE activity seems to be a useful method for the identification of T and B cells in lymphoid tissue sections and smears of malignant lymphomas.
