Restoring T-helper 17 cell/regulatory T-cell balance and decreasing disease activity by rapamycin and all-trans retinoic acid in patients with systemic lupus erythematosus.

OBJECTIVE

This study aimed to investigate the effect of rapamycin (RAPA) alone or in combination with all-trans retinoic acid (ATRA) on the T-helper 17 (Th17) cell/regulatory T-cell (Treg) balance in patients with systemic lupus erythematosus (SLE) and to evaluate the clinical efficacy.

METHODS

Seventy patients with SLE were enrolled. They were randomly and equally divided into RAPA and RAPA + ATRA groups. The number of Th17 and Treg cells was measured by flow cytometry before and after treatment for 6, 12 and 24 weeks. The SLE Disease Activity Index (SLEDAI) score and the prednisone dose before and after treatment were used to evaluate the efficacy between the two groups.

RESULTS

In both groups, at different time points after treatment, the number of Th17 cells ( = 0.003) and Th17/Treg ratio ( = 0.044) reduced, while the number of Treg cells ( = 0.574) tended to increase. The SLEDAI score and the dose of prednisone decreased significantly ( < 0.001). There was no significant difference in the number of Th17 cells ( = 0.089), Treg cells ( = 0.059), Th17/Treg ratio ( = 0.580), SLEDAI score ( = 0.127) and the dose of prednisone ( = 0.329) between the two groups.

CONCLUSION

Disease activity in SLE patients reduced with RAPA alone or in conjunction with ATRA, reducing glucocorticoid requirement. One of its mechanisms of action may be regulating the Th17/Treg cell balance, which provides a new model for the pathogenesis and potential treatment of SLE.