In Vitro Effects of Thymosin on T-Cell Subsets in Systemic Lupus Erythematosus

The possible immunomodulatory influence of thymosin on lymphocytes from patients with active systemic lupus erythematosus (SLE) has been evaluated. Such patients have decreased numbers of T-suppressor (Tγ) cells and normal numbers of T-helper (Tμ) cells, resulting in an abnormally low Tγ/Tμ ratio. In vitro incubation of lymphocytes from active SLE patients with thymosin resulted in a normalization of the Tγ/Tμ ratio. This occurred because of a decrease in Ty cells rather than an increase in Tγ cells. The normalization of Tγ/Tμ ratios in vitro in the presence of thymosin is compatible with possible in vivo immunomodulatory effects of these peptides.