The imbalance of Th17 and regulatory T cells in pemphigus patients.

Unlabelled: Pemphigus is a complex dermatologic autoimmune bullous disease whose pathogenic mechanism is not fully understood. Anti-desmoglein-1 (Dsg1) and anti- Dsg3 autoantibodies play an important role in the pathogenesis of pemphigus.

Objectives: To investigate the role of T-helper17 (Th17) and regulatory T (Treg) cells in the pathogenesis of pemphigus in fifty-one patients and twenty-six healthy individuals (control group).

Methods: Levels of CD3(+)CD8(-) IL-17 expressing Th cells and CD4(+)CD25(hi)Foxp3(+) Treg cells were determined by FACS in both groups, along with anti-Dsg1 and Dsg3 antibody titers. An analysis of the correlation between Th17 and Treg cells was performed.

Results: Th17 cell numbers were significantly higher in pemphigus patients than in normal controls (P = 0.014), especially in the acute onset and chronic active stages (P = 0.004 and 0.022). Conversely, Treg cells in pemphigus patients were significantly fewer than in the control group (P<0.001). The same trend was observed between the acute onset and the remittent stage patients (P = 0.006). We found a negative correlation between Th17 and Treg cell populations (r = -0.532, P<0.001). Anti-Dsg1 and Dsg3 antibody titers were higher in patients in the active stage than in the remittent stage, with an increased IgG4/IgG1 subclass ratio. There was no statistically significant correlation between Th17/Treg ratios and anti-Dsg1 or Dsg3 antibody titers.

Conclusion: These findings show an imbalance of Th17 and Treg cell populations in pemphigus patients, which might result in the activation and proliferation of effector T cells, further up-regulating B cell activity and antibody production.