Phenotypic correction of Age-associated functional decline in murine immune cells by Thymax, a thymic extract.

Background: We have recently demonstrated that Thymax, a gross thymic extract, induces the functional activity of human dendritic cells (DCs) in vitro. In this study, the role of Thymax in phenotypic correction of age-associated functional decline in immune cells in mice was evaluated.

Materials And Methods: C57BL/6 mice (13 months old) were treated with Thymax orally (20% v/v) for 4 weeks. Different splenic cell types, dendritic cells (DCs), B-cells, T-cells and natural killer (NK) cells, were analyzed using flow cytometry.

Results: Treatment with Thymax resulted in: i) a significant increase in the percentages of DCs (1.6-fold), B-cells (7-fold) and T-cells (5-fold) over the control (p<0.05); ii) an increase in the percentages of activation markers (CD25 and CD69) of CD4(+) and CD8(+) T-cells; and iii) an enhancement in NK activity. Thymax showed no adverse side-effects.

Conclusion: Thymax might have a role in reversing immune dysfunction in the elderly.