Identification of cynomolgus T lymphocytes by acid alpha-naphthyl acetate esterase staining and spontaneous erythrocyte rosette formation.

Cell surface markers and cytochemical characteristics of cynomolgus lymphocytes were studied. The proportion of lymphocytes with spot-like distribution of acid alpha-naphthyl acetate esterase (ANAE) activity was similar to that of lymphocytes which form spontaneous rosette with sheep erythrocytes (E rosette) in individual monkeys. Fractionation by E rosette formation or passage through nylon wool column selectively enriched ANAE-spot-positive (ANAE) lymphocytes and resulted in twofold increase in blastogenic response when stimulated with phytohemagglutinin (PHA) or concanavalin A (Con A). In contrast, treatment of lymphocytes with rabbit anticynomolgus thymocyte serum (ATS) plus complement resulted not only in the depletion of both E rosette forming and ANAE lymphocytes, but also in the reduction of lymphocyte blastogenic response to PHA or Con A. In cryostat sections of lymphoid tissues. ANAE lymphocytes were found to reside in T dependent areas such as paracortical areas and periarterial lymphatic sheaths but not in T independent areas. ANAE activity was absent, however, in cortical thymocytes and lymphoblasts transformed by phytomitogens, suggesting that immature T lymphocytes are ANAE negative. These findings indicate that the histochemical demonstration of ANAE activity and E rosette formation serve useful markers for T lymphocytes in cynomolgus monkeys as in human.