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.