Effect of thymic hormones on induction of experimental allergic encephalomyelitis in old mice.

This study was aimed at restoring decreased T-cell functions and reduced susceptibility to proteolipid apoprotein (PLP) induced-experimental allergic encephalomyelitis (EAE) in old mice with thymic hormones. Thymosin fraction 5 (TF-5) and serum thymic factor (FTS) had no significant in vitro and in vivo effect on proliferative responses to PLP and concanavalin A (Con A), and on EAE induction in young and old mice. These results suggest that decreased T-cell functions cannot be restored by these thymic hormones tested.