Functional roles of Phe(12) of deacetyl-thymosin β4 in the impaired blastogenic response of uraemic T-lymphocytes

Phe(12) of deacetyl-thymosin β(4) is one of the structural essentials for restorative effect on the impaired blastogenic response of uraemic T-lymphocytes. In order to evaluate the functional roles of this phenyl group in the restorative effect on impaired T-lymphocytes, two analogues, [1- Nal(12)]deacetyl-thymosin β(4) and [Cha(12)]deacetyl4 thymosin β(4), were synthesized by a solid-phase method and evaluated for restorative effect on the impaired blastogenic response of uraemic T-lymphocytes. The results indicated that [1-Nal(12)]deacetyl-thymosin β(4) which had a bulky naphthyl ring showed a stronger restorative effect than that of deacetyl-thymosin β(4), but it was slightly weaker than that of [Phe(4F)(12)]deacetyl-thymosin β(4). However, [Cha(12)]deacetyl-thymosin β(4) showed no restorative effect on the impaired blastogenic response of uraemic T-lymphocytes.