A Study of the Changes of T Helper 17 Cells and Regulatory T Cells in Herpes Zoster

BACKGROUND Immunosuppression and age-related deficiencies in cell-mediated immunity are important factors for the reactivation of latent varicella-zoster virus (VZV). CD4+CD25+Foxp3+ regulatory T (Treg) cells and T helper 17 (Th17) cells are closely associated with various viral infections. OBJECTIVE We analyzed Treg cells and Th17 cells in patients with herpes zoster and investigated their relationship with the reactivation of latent VZV. METHODS Treg and Th17 cells in peripheral blood and the ratio of Th17 to Treg cells were examined in patients with herpes zoster and healthy controls. Changes between pre-treatment and post-treatment estimates of Treg and Th17 cells and clinical parameters in patients with herpes zoster were also analyzed. RESULTS The proportion of circulating Th17 cells and the Th17/Treg cell ratio were significantly higher in patients with herpes zoster than controls (p=0.012, 0.013), but there was no significant difference in the proportion of Treg cells between groups. There was no significant difference in the proportions of Treg and Th17 cells and the Th17/Treg cell ratio before and after treatment and between the non-postherpetic neuralgia and postherpetic neuralgia groups. Changes in Treg and Th17 cells and the Th17/Treg cell ratio were not significantly correlated with changes in the visual analog scale. Body surface area was significantly correlated with Treg cells, Th17 cells, and the Th17/Treg cell ratio (p=0.022, 0.002, 0.004). CONCLUSION An imbalance between Th17 and Treg cells is associated with the reactivation of VZV, which may contribute to pathogenesis of herpes zoster.