IE63-specific T-cell responses associate with control of subclinical varicella zoster virus reactivation in individuals with malignancies

BACKGROUND: Reactivation of the varicella zoster virus (VZV) is more common in patients with malignancies; however, the molecular and cellular mechanisms underlying this susceptibility are unclear. METHODS: Using ex vivo interferon-γ ELISpot assays, we set out to analyse VZV-specific immune responses in a large cohort of patients with malignancies. RESULTS: We observed that patients with malignancies had impaired VZV-specific T-cell responses, particularly in those with haematological malignancies and breast carcinoma. Immediate-early protein 63 (IE63)-specific T-cell responses were significantly impaired in those with subclinical VZV re-activation. CONCLUSIONS: Our results suggest that T-cell responses to IE63 are important in controlling VZV replication.