Low-dose IL-2 therapy restores imbalance between Th17 and regulatory T cells in patients with the dermatomyositis combined with EBV/CMV viremia.

OBJECTIVE

Dermatomyositis (DM) is closely associated with infection, the levels of peripheral lymphocyte subpopulations are rarely studied in patients with DM combined with Epstein-Barr virus (EBV)/cytomegalovirus (CMV) infection. Here, we aimed to observe the level of lymphocyte subsets, especially Th17, regulatory T (Treg) cells in DM combined with EBV/CMV viremia, and explore the effects of short-term low-dose IL-2.

METHODS

34 DM patients combined with EBV/CMV viremia (DM infection group), 31 DM patients without infection (DM non-infection group) and 20 healthy controls were entrolled in our study. In DM infection group, 13 patients received low-dose IL-2 at 0.50 Million IU/day for a five-day course on the basis of conventional treatment. All subjects had completed the decetion of the absolute numbers of lymphocytes subsets in peripheral blood by flow cytometry.

RESULTS

The infection group had significant decreases levels of total T, total B, NK, CD4 + T cells and CD4 + T subsets (Th1, Th2, Th17, Treg cells). Compare to the healthy controls, Th17 cells was significantly reduced in the infection group, but not in the non-infection group (P < 0.001 vs. P = 0.171). After low-dose IL-2 therapy, the levels of Treg (P = 0.001) cells and Th17 cells were significantly elevated, re-balancing the Th17 and Treg proportions.

CONCLUSIONS

The absolute numbers of Th17 and Treg cells in DM patients with EBV/CMV viremia is further reduced. In addition to Treg cells, a decrease in Th17 cells may be also a crucial feature. Low-dose IL-2 treatment may be beneficial and safe prospect immunomodulatory therapy to restores imbalance between Th17 and Treg cells for these patients. Low-dose IL-2 therapy may be a new prospect field with some challenges such as long-term immunoregulatory utility in various virus infection.