Impairment of T immunoregulatory activities in the induction of antibody specific response in aged humans.
T helper (Th) and T suppressor (Ts) functions on the induction of specific antibody response have been studied in 80 aged individuals by means of a plaque-forming cell assay. Of the subjects 45.2% exhibited a reduction of Ts activity on Ig production by adding Concanavalin A (Con A) to cultures on day 0, while 35.7% of aged donors showed a decrease of Th functions by supplementation of Con A on day 2. A small number of individuals displayed a combined deficit (Th + Ts). Furthermore, these defects seem to be related to soluble suppressive factors which might adhere to cell surface. In fact, preincubation of peripheral blood mononuclear cells (PBMC) before their addition to cultures and resuspension in fresh medium normalized the immunoregulatory defects. On the other hand, overnight supernatants from old PBMC transferred to young PBMC cultures induced the same deficit observed in the aged cell suspensions. Finally, Zinc chloride supplementation to cultures was able to correct the deficient Th activity only. These data suggest an additional defect of immunoregulation in the elderly.
Antonaci
S
S
Jirillo
E
E
Gallitelli
M
M
Garofalo
A R
AR
Bonomo
L
L
D000293:Adolescent; D000328:Adult; D000368:Aged; D000375:Aging; D002478:Cells, Cultured; D002712:Chlorides; D005260:Female; D006462:Hemolytic Plaque Technique; D006801:Humans; D007213:Indomethacin / Q000494:pharmacology; D008214:Lymphocytes / Q000187:drug effects; D008297:Male; D009000:Monocytes / Q000187:drug effects; D006377:T-Lymphocytes, Helper-Inducer / Q000276:immunology*; D050378:T-Lymphocytes, Regulatory / Q000276:immunology*; D015032:Zinc / Q000494:pharmacology; D017967:Zinc Compounds
D002712:Chlorides; D017967:Zinc Compounds; C016837:zinc chloride; D015032:Zinc; D007213:Indomethacin