Correlation of angiogenic growth factors and inflammatory cytokines with the clinical phenotype of ocular tuberculosis

Abstract

Purpose: To determine the correlation of angiogenic growth factors and inflammatory cytokines with the clinical phenotype of ocular tuberculosis (OTB).

Methods: Vitreous fluid was analysed for cytokines in patients with OTB and non-OTB uveitis using multiplex fluorescent bead-based flow cytometric assay. The clinical phenotypes were recorded and correlated with vitreous biomarkers.

Results: Vitreous humour from OTB patients had elevated levels of interleukin-10 (IL-10), IL-17-A, interferon-gamma (IFN-γ), and tumour necrosis factor-alpha (TNF-α). Angiopoietin (Ang-2) levels were higher in the panuveitis phenotype. OTB posterior uveitis phenotype had relatively higher vascular endothelial growth factor (VEGF) levels and lower fibroblast growth factor (FGF) levels. Additionally, eyes with choroiditis and vasculitis had elevated levels of VEGF and Ang-2 with FGF downregulation. Both IFN-γ and IL-10 were upregulated in the choroiditis phenotype of OTB.

Conclusion: Angiogenic growth factors and inflammatory cytokines were altered in the vitreous humour of OTB patients. IFN-γ, VEGF, and IL-10 levels are increased in choroiditis and vasculitis phenotypes. Receiver operating characteristic (ROC) curve analysis further emphasized the importance of the IFN-γ assay in the diagnosis of OTB.

Keywords: Angiopoietin; Growth factors; Inflammatory cytokines; Ocular tuberculosis; Serpiginous like choroiditis; Uveitis.