Cytochemical study of human lymphocytes stimulated by PHA in function of donor age.

The 3H-AM binding reflects the structural changes involved in the cellular differentiation. This parameter was studied during blastic transformation of human lymphocytes, in relation to the age of the donor. Although they are individual variations, the 3H-AM binding is higher in the young group than in the aged subjects, as well as the blast transformation score. These results indicate that the weak lymphocyte response to the mitogen lectine (PHA) stimulation could be related to some age-induced structural alterations of the chromatin, resulting in an irreversible blockage in G1, at least in some of the T lymphocytes.