The association between the interleukin-10 cytokine and CC chemokine ligand 5 polymorphisms and mycetoma granuloma formation.

Mycetoma is a progressive and destructive chronic granulomatous subcutaneous inflammatory disease caused by bacteria and fungi. The genetic determinants for susceptibility to and the development of mycetoma are unclear. Polymorphisms in genes encoding for cytokines and chemokines usually influence the efficiency of the immune response to infection and are associated with disease susceptibility and progression. Therefore, we hypothesized that polymorphisms of CC chemokine ligand 5 (CCL5) and interleukin-10 (IL-10) promoter regions might contribute to the initiation, susceptibility, and severity of eumycetoma. This case-control study included 149 mycetoma patients and 206 healthy matched controls. In the study population, three functional single nucleotide polymorphisms (SNPs) in CCL5 and two in IL-10 were genotyped using polymerase chain reaction and restriction fragment length polymorphism (PCR-RFLP). Significant differences in allele distribution were demonstrated for CCL5 -28 C/G (P < 0.0001), CCL5 In1.1 T/C (P < 0.0001) and IL-10 -592 A/C. Since in previous studies it was demonstrated that the genotypes obtained for CCL5 and IL-10 were connected with CCL5 and IL-10 production we measured the serum levels of CCL5 and IL-10 in mycetoma patients and healthy controls. Elevated serum levels for both CCL5 and IL-10 were found in mycetoma patients and we describe that genetic differences in CCL5 and IL-10 are associated with the development of the mycetoma granuloma.