DECREASED MATURATION OF T-CELL POPULATIONS IN THE HEALTHY ELDERLY - INFLUENCE OF NUTRITIONAL FACTORS ON THE APPEARANCE OF DOUBLE-NEGATIVE CD4-, CD8-, CD2+ CELLS

Aging is characterized by decreased T-cell functions partly related to increase of T-cell immature subsets. In carefully selected population s we explored influences of decreased nutritional levels and/or diseas es on the appearance of T-cell immaturity in elderly persons. Decrease of nutritional status is associated in healthy elderly fitting the '' SENIEUR'' protocol with decreased mature T-cells (CD3+), (CD8+) and in creased immature double-negative T-cells (CD2+CD4-CD8-). Diseased unde rnourished patients express the same variations in T-cell subsets plus decreased CD4+ and increased double-positive T-cells (CD2+CD4+CD8+). This seems to indicate that aging-associated immature T-cells in perip heral blood are generated at two different, thymic and extra-thymic si tes of maturation.