Nonspecific alpha-naphtyl acetate esterase activity of T-lymphocytes: Study in healthy newborns and children, in immune deficiencies and juvenile rheumatoid arthritis

Abstract

The aim of this study was to compare the E rosette-forming cells and nonspecific alpha naphtyl esterase (ANAE)-positive lymphocyte values in normal and pathologic situations. In newborns, the ANAE-positive lymphocytes represented less than 60% of the E rosette population. During the first year of life, E rosette- forming cells (E-RFC) reached normal values as soon as one month whereas only three-fourths of the T cells exhibited an ANAE-positive staining. In adult T cell populations, nearly 90% were ANAE-positive. Our observations of immune deficiencies suggested that the relative proportions of E-RFC and ANAE- positive lymphocytes were generally comparable to normal values. However, in the majority of the patients with very low or absent E-RFC (severe combined immune deficiencies, Di George syndrome, and congenital rubella), some ANAE-positive lymphocytes could be detected. Our immunologic survey shows that the ANAE- positive Iymphotytes were in a normal range 2 years after a bone marrow transplantation in severe combined immune deficiencies patients. One child who exhibited a normal amount of E-RFC and whose lymphocytes failed to respond in vitro to mitogens had practically no ANAE-positive lymphocytes. An elevated amount of ANAE-positive cells in juvenile rheumatoid arthritis may reflect an augmentation of the T helper functions which permanently stimulated in vivo immunoglobulin production. Speculation: The alpha-napthtyl acetate esterase-positive lymphocytes have been shown to belong to the T helper subpopulation. Various proportions of these cells among T-lymphocytes can be expected in normal subjects such as newborns and infants where the immune system is considered as immature and in situations involving immune regulation such as immune deficiencies and chronic hyperimmune diseases. © 1981 International Pediatric Research Foundation, Inc.