Age-related differences in granulocyte Chemotaxis and degranulation

1. In the present study we have demonstrated that human peripheral blood granulocytes from elderly subjects exhibit reduced chemotaxis and degranulation in response to stimulation with fMet-Leu-Phe.

2. Cyclic AMP levels in non-stimulated cells were not significantly different (mean ± sem): 4.8 ± 0.6 and 3.9 ± 0.4 pmol/10⁷ cells for young and elderly respectively. Stimulation with fMet-Leu-Phe (5 × 10⁻⁷ mol/l) for 30 s induced the production of cyclic AMP: 8.4 ± 0.5 and 6.7 ± 0.3 pmol/10⁷ cells for young and elderly.

3. These findings, together with those previously published by us, suggest that cyclic AMP production and cellular functions which this molecule participates in are reduced in cells from elderly individuals.