Monocyte- and cytokine-mediated effects on T immunoregulatory activity in the elderly.
Aged individuals exhibit an impairment of T helper and/or T suppressor activity on B cell function in an antibody-specific induction system. Further evidence is now provided that soluble suppressive factors acting on monocytes play a key role in such deficits. In fact, overnight preincubation of isolated monocytes and supplementation of autologous lymphocytes reverses the immunoregulatory imbalance. The suppressive factors are also responsible for a decreased interleukin 2 (IL-2) synthesis since a similar pretreatment of cell suspensions or exogenous human IL-1 and/or IL-2 supplementation of aged cell cultures leads to a recovery of T regulatory effects on B cell differentiation. Similar effects are observed in the presence of thymopentin, a well known IL-2 inducer. Interferon alpha and gamma addition to cultures gives rise to a restoration of T immunoregulatory effects. These findings suggest that several mechanisms are involved in the depressed T immunoregulatory activity in the elderly.
Antonaci
S
S
Fisiopatologia Medica, University of Bari Medical School, Italy.
Jirillo
E
E
Munno
I
I
Colizzi
M
M
Polignano
A
A
Bonomo
L
L
D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000276:immunology*; D001685:Biological Factors / Q000276:immunology*; D016207:Cytokines; D005260:Female; D006801:Humans; D007372:Interferons / Q000494:pharmacology; D007378:Interleukins / Q000096:biosynthesis*; D008297:Male; D009000:Monocytes / Q000276:immunology*; D013601:T-Lymphocytes / Q000187:drug effects / Q000276:immunology*
D001685:Biological Factors; D016207:Cytokines; D007378:Interleukins; D007372:Interferons