Evidence for adenosine adenosinedeaminase lymphocyte system impairment in ageing.
Age related immune disfunctions are the result of humoral and cellular changes of the immune system and reflect major alterations of T cell subpopulations which concern cyclic nucleotides and their precursors. There are now many reports showing that adenosine can affect some phenotypic and functional lymphocyte characteristics. We have found that a short preincubation (30') with adenosine can inhibit proliferative responses of peripheral blood lymphocytes to polyclonal mitogen Concanavalin A in young healthy controls (p less than 0.05) but not in aged healthy subjects. These data led us to the hypothesis that an impairment of the adenosine-adenosinedeaminase system could play an important role in the age-associated decline of immune responses. Our results show a highly significant reduction (16.45 +/- 3.56 vs 24.42 +/- 9.5 p less than 0.001) of adenosinedeaminase activity in peripheral lymphocytes of aged humans (mean age 75.5 +/- 6.7 range 23-30). Preliminary studies suggest that this alteration could be responsible to some extent, for the decreased mitogenic response of lymphocytes reported in ageing.
Crosti
F
F
Istituto Scientifico San Raffaele, Università degli Studi di Milano, Italy.
Ciboddo
G F
GF
Barbieri
M C
MC
Inversi
F
F
Pavoni
D
D
Quarenghi
S
S
Navone
P
P
Vezzoni
P
P
Rugarli
C
C
D000241:Adenosine / Q000494:pharmacology*; D000243:Adenosine Deaminase / Q000378:metabolism*; D000368:Aged; D000375:Aging / Q000276:immunology* / Q000378:metabolism; D003208:Concanavalin A; D006801:Humans; D008213:Lymphocyte Activation / Q000187:drug effects*; D008214:Lymphocytes / Q000201:enzymology*; D008875:Middle Aged; D009700:Nucleoside Deaminases / Q000378:metabolism*
D003208:Concanavalin A; D009700:Nucleoside Deaminases; D000243:Adenosine Deaminase; D000241:Adenosine