Increased Prostaglandin E2 Production by Concanavalin A-Stimulated Splenocytes of Old Mice

Production of prostaglandin E2 (PGE2) was examined in splenocyte cultures of C57BL/6J mice aged between 1 and 34 months. A significant increase in PGE2 production, in response to polyclonal stimulation by concanavalin A, was found after 24 and 48 h of incubation in all age groups. However, activated splenocytes taken from mice of the oldest group (28–34 months) produced 2- to 3-fold greater amounts of PGE2, as compared with the younger groups, and a trend towards an age-associated increase was apparent from the age of 18 months onwards. No significant age-related difference in PGE2 levels was observed in unstimulated cultures. The results obtained conform to the hypothesis that PGE2 is involved in the age-related changes in lymphocyte functions. Increased PGE2 production in response to mitogenic stimuli may affect the profile of cytokines and may limit cell-mediated immune responses in aging, such as lymphocyte proliferation and natural killer cell activity.