Cytomegalovirus-Specific T Cell Immunity and Clinical Associations in Patients With CMV Anterior Uveitis

The purpose of this study was to investigate T cell immunity in patients with cytomegalovirus anterior uveitis (CMV AU) and examine their correlation with clinical manifestations.

Peripheral blood mononuclear cells were isolated from 31 patients with CMV AU and 32 CMV-seropositive healthy controls. Cells were stimulated in vitro with CMV antigens IE1 and PP65. Flow cytometry was performed to evaluate the expression of cytokines IFN-γ, TNF-α, granzyme B, and PD-1 in CD4 and CD8 T cells. Clinical parameters, including disease duration, the mean deviation (MD) from 24-2 visual field (VF) and corneal endothelial cell density, were collected and analyzed for correlations with immunological findings.

Patients with CMV AU had a median disease duration of 4 years (interquartile range [IQR] = 2-7 years), moderate VF loss (MD = -8.27 decibels [dB], SD = 8.04), and a median corneal endothelial cell density of 2076 cells/mm² (IQR = 1078-2378). Patients with CMV AU exhibited baseline cytokine levels comparable to seropositive controls but showed increased IFN-γ production in CD4 T cells and heightened IFN-γ and TNF-α responses in CD8 T cells following CMV antigen stimulation. In patients with CMV AU, greater CMV-specific IFN-γ and TNF-α responses but not granzyme B or PD-1 expression were linked to longer disease duration after adjusting for age. Greater CMV-specific IFN-γ activity was associated with higher corneal endothelial cell density but more severe glaucomatous VF loss, after adjustment for age and disease duration.

Our study highlights that immune sensitization and CMV-specific IFN-γ T-cell responses may shape the clinical presentation of CMV AU.