RESUMO
Abstract Background: Leprosy represents a long-term communicable disease resulting from Mycobacterium leprae infection. IL-17A is one of the pro-inflammatory cytokines that protects humans against many fungal and bacterial pathogens. Objective: To investigate IL-17A (rs2275913) gene polymorphism and its circulating level in leprosy patients, and to correlate the detected results with different clinical aspects of leprosy in the investigated patients. Methods: 60 patients with leprosy, and 29 age and sex-matched volunteers were investigated for IL-17A serum level and IL-17A single nucleotide polymorphism (SNP) by ELISA and RFLP-PCR respectively. Results: IL-17A serum level was significantly higher in leprosy patients than in controls (p = 0.034), and in TL than LL (p = 0.017). IL-17A (rs2275913 A/G) G allele and GG genotype were associated significantly with LL (p = 0.005and 0.001 respectively). IL-17A (rs2275913 A/G) AG genotype carriers demonstrated the highest IL-17A serum levels; however, its lowest levels were found in IL-17A (rs2275913 A/G) AA genotype carriers (p = 0.005). Grade 2 disability (p = 0.030) and positive slit skin smear (SSS) (p = 0.005) were significantly associated with IL-17A (rs2275913 A/G) GG genotype. Study limitations: The small number of studied subjects. Conclusions: IL -17A may have a pivotal role in leprosy pathogenesis. IL-17A (rs2275913) GG genotype plus G allele might be related to the development of LL in the Egyptian population.