Complement C5 Gene Confers Risk for Acute Anterior Uveitis

Area of Science:

• Immunogenetics
• Ophthalmology
• Rheumatology

Background:

• Polymorphisms in complement components C3 and C5 are implicated in various immune-mediated diseases.
• The specific association between C3 and C5 single nucleotide polymorphisms (SNPs) and acute anterior uveitis (AAU) remains unexplored.

Purpose of the Study:

• To investigate the association between C3 and C5 gene polymorphisms and the risk of developing AAU.
• To explore the relationship between specific C5 genotypes and C5 serum concentrations, as well as interleukin-17 (IL-17) production.

Main Methods:

• Genotyping of six C3 SNPs and four C5 SNPs was conducted in 395 AAU patients with ankylosing spondylitis (AS), 397 AAU patients without AS, and 597 healthy controls using PCR-RFLP and TaqMan SNP assays.
• Messenger RNA (mRNA) expression levels were quantified via real-time PCR.
• Cytokine production and total C5 serum concentrations were measured using ELISA.

Main Results:

• The GG genotype of the C5 rs2269067 SNP showed a significantly increased frequency in AAU patients (with and without AS) compared to healthy controls.
• Individuals with the rs2269067 GG genotype exhibited higher C5 mRNA and serum concentrations.
• An elevated production of interleukin-17 was observed in individuals with the rs2269067 GG genotype.

Conclusions:

• The C5 rs2269067 GG genotype represents a risk factor for AAU in the studied Chinese population.
• This genotype is associated with elevated C5 serum levels and increased IL-17 production, suggesting a potential mechanism for AAU development.