Change in the Capacity of Spontaneous Restoration ofDifferentiation Antigens of T-Lymphocytes in Relation to Age

Overview

Background.
During physiological ageing changes of the immune system take place at several levels. The objectiveof the submitted work was to compare the ability of spontaneous restoration of selected differentiation antigens onlymphocytes in the peripheral blood stream after previous trypsin treatment in a group of healthy elderly and adultsubjects.Methods and Results. Twenty-four adults were examined (19 - 59 years) and 36 elderly subjects (60 - 90 years).Isolated lymphocytes from the peripheral blood stream were treated with trypsin and then incubated in a cultivationmedium. The authors investigated the capacity of restoration of differentiation antigens CD2, CD4, CD8 andCD45RA.Antigen CD2 was not restored in any of the investigated groups to original levels. However the difference betweenits expression on lymphocytes before trypsin treatment and on lymphocytes after 16-hour incubation was higher inthe elderly subjects 16% (p < 0.001) than in the group of adults 7% (p < 0.01). Restoration of antigen CD4 was inboth investigated groups almost equal. The number of CD8+ T-lymphocytes was in elderly people lower (p < 0.05),spontaneous restoration of antigen CD8 did not differ among the investigated groups and reached in both instancesthe baseline value. Antigen CD45RA was restored more slowly in elderly subjects, the difference between groupswas at borderline of statistical significance (p < 0.0595).Conclusion. From the results ensues that during physiological ageing the ability of spontaneous restoration ofantigens CD2 and CD45RA declines but not of antigens CD4 and CD8. So far there is no unequivocal explanationwhy this change occurs, it is probably conditioned by several factors. Investigation of these changes and an attemptto influence them can help to understand age-conditioned immunological dysregulation, its consequences and thepossibility to influence them by treatment.

Key words:
ageing, trypsin, treatment, restoration, CD2, CD4, CD8, CD45RA.