Characterization of the varicella zoster virus (VZV)-specific intra-ocular T-cell response in patients with VZV-induced uveitis

Varicella zoster virus (VZV) is a well-known cause of infectious uveitis. The aim of this study was to characterize the VZV-specific T-cell response in eyes of patients with VZV-induced uveitis. T-cell lines (TCL) were generated by mitogenic stimulation of intra-ocular fluid (IOF) samples obtained from eight patients with VZV-induced uveitis. Two patients with herpes simplex virus (HSV)-induced uveitis were included as disease controls. Characterization of individual T-cells in the TCL was performed by stimulating the TCL with mock, HSV-1 and VZV antigen pulsed autologous B cells and subsequent flow cytometric analyses. Virus specificity and phenotype of the T-cells were identified by simultaneous detection of intracellular gamma interferon and cell surface markers CD4, CD8, CD3 or T-cell receptor (TCR) beta chain variable region (TCRBV) usage. The TCL obtained from patients with HSV-1-induced uveitis contained higher numbers of T-cells reactive to HSV-1 compared to VZV. VZV-specific T-cells were detected in all TCL of the patients diagnosed with VZV-induced uveitis. Four out of six TCL obtained from patients with VZV-induced uveitis that were assayed for both viruses, contained higher numbers of T-cells reactive to VZV compared to HSV-1. Detailed analyses of the TCL of two patients demonstrated that the VZV reactivity within the assayed TCL was dominated by T-cells expressing one specific TCRBV gene. The data implicate that VZV-reactive T-cells infiltrate and participate in the local inflammatory response in eyes of patients with VZV-induced uveitis.