Abstract
Purpose::
Experimental data has demonstrated a relevant role for IL-10 in the modulation of acute ocular toxoplasmosis in murines. Therefore, we aim to investigate the possible association between IL-10 (-1082G/A) polymorphism and toxoplasmic retinochoroiditis in humans.
Methods::
Cross-sectional study which included one hundred Brazilian patients meeting well-defined criteria for the diagnosis of toxoplasmic retinochoroiditis and fifty age and gender matched control subjects with no signs of ocular toxoplasmosis in whom anti-toxoplasma antibody analysis revealed positive immunoglobulin G titers. Genomic DNA was obtained from oral swabs of all subjects and amplified using the polymerase chain reaction (PCR) with specific primers flanking the locus -1082 of IL10. PCR products were submitted to restriction endonuclease digestion and analyzed by polyacrylamide gel electrophoresis, to distinguish alleles G and A of the IL10 gene, allowing for the determination of the genotypes and detection of the polymorphism.
Results::
There were no statistically significant associations among -1082A allele and the occurrence of toxoplasmic retinochoroiditis (P = 0.80; x² = 0,065). In addition, subgroup analysis considering only patients with a history of more of one year of follow-up demonstrated significant associations among -1082A allele and disease recurrence (defined as 2 or more episodes) toxoplasmic retinochoroiditis ( p = 0.03; x² = 4,602).
Conclusions::
Our data suggest that the polymorphism in the locus -1082 of IL-10 gene may not be associated with occurrence of toxoplasmic retinochoroiditis, but may be associated with the recurrence of the disease in humans.
Keywords: immunomodulation/immunoregulation • chorioretinitis • gene/expression