Enhancement of the reponse of ageing mouse lymphocytes by In vitro treatment with lecithin

The effect of treatment with phosphatidylcholine (lecithin) has been examined on splenocytes from young (6 months) and aged (>20 months) (C3H/eB × C57BL/6)F1 male mice, by probing their responsiveness to proliferative signals of mitogens and mixed lymphocyte reaction. This study was initiated since old mice have been known to manifest an increased ratio of cholestrol: phospholipids (C/PL) in their plasa membranes. Unlike the case in young mice, enhancement in proliferative responses was demonstrated on cells from the old after incubation with lecithin. This enhanceent was achieved using a variety of methods by which lymphocytes were exposed to the lipids, and which were all designed to reduce the C/PL ratio in the plasma membrane. The observed differences in response to lecithin treatment between young and old did not stem from different extents of lipid incorporation, and seems unlikely to be a result of modified binding of the mitogens after treament with the lipid. The data suggest that the normal functional performance of specific reactions, which decline with age, may be restored artificially at an appropriate age, if other complementary functions have not been damaged.