Varicella-zoster virus-specific cell-mediated immunity in subjects with herpes zoster

Though cell-mediated immunity (CMI) against varicella-zoster virus (VZV) is critical for prevention of the onset of herpes zoster (HZ), clinicians currently lack a simplified procedure to monitor CMI. We have recently developed an assay, called the IFN-γ release assay, and showed that it is a simple and reliable method to determine VZV-specific CMI. In the present study, we applied an IR assay to measure the VZV-specific CMI of patients with HZ. VZV-specific CMI levels were significantly high at the onset of the disease, but were decreased several weeks later. In contrast, CMI VZV-specific antibody titers increased in convalescent phase compared to those in acute phase. Thus, this technology is likely to be very useful in monitoring ongoing VZV-specific immune status.