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

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