The Signature of Serum Modified Nucleosides in Uveitis.

Purpose: This study aims to evaluate the metabolism of serum-modified nucleosides in uveitis by using liquid chromatography-tandem mass spectrometry (LC-MS) and to develop potential diagnostic biomarkers for uveitis.

Methods: Forty-two patients with different subtypes of uveitis (idiopathic uveitis, Vogt-Koyanagi-Harada [VKH] disease, and ankylosing spondylitis [AS]) and 32 healthy controls were recruited in this retrospective case-control study. The concentrations of 23 modified nucleosides in patient serum were quantified by LC-MS. The data was statistically analyzed with SPSS and GraphPad Prism.

Results: The data revealed that 13 out of 23 modified nucleosides (m6A, m1A, m6Am, Cm, ac4C, Gm, m1G, m2G, m2,2G, Um, m3U, m5U, and m5Um) effectively showed quantifiable chromatographic peaks. The statistical results indicated that there were extremely significant differences for m2G, Gm, Cm, and m1G between healthy controls and uveitis patients. The differences for Gm, m6A,and m5U were able to further assort idiopathic uveitis and uveitis with systemic inflammation including VKH and AS. Interestingly, each specific subtype of uveitis is characterized by its signature combination of serum-modified nucleotides comparing with healthy controls.

Conclusions: This study revealed that the metabolism of serum-modified nucleosides in uveitis patients display significant differences from healthy controls. The signature combination of serum modified nucleotides for each subtype of uveitis may be applied for the potential diagnosis of uveitis.