Effect of the chemokine receptor CCR5 in the development of American cutaneous leishmaniasis in a Southern Brazilian population.

American cutaneous leishmaniasis (ACL) shows a wide spectrum of clinical and immunopathological manifestations. The CCR5 chemokine receptor directs the immune response to a Th1 pattern and the mutant allele of this genotype (Δ32/Δ32) results in a less effective response, thus leading to a milder inflammation. The objective of the present study was to investigate the effect of the CCR5 chemokine receptor in the pathogenesis of ACL in a population of Southern Brazil. The frequency of the genotypes and their association with ACL were studied in 111 patients and compared with 218 control subjects. Genotyping was performed using samples amplified by polymerase chain reaction with sequence specific primers (PCR‑SSP). The groups varied in chronological age (P<0.00001), but showed no differences in gender (P=0.0696) or ethnicity (P=0.2944). The frequency of the CCR5/Δ32 genotype did not differ between the patient and control groups (P=0.3009). The Δ32/Δ32 deletion was not observed in any individual involved in the study. The analysis of the genotypes observed no significant difference in the frequency of the CCR5/Δ32 genotype between the ACL and control groups, however the subgroup of patients with a recurrence of the lesion showed a higher frequency of the CCR5/Δ32 mutation (P=0.020), indicating a possible effect of this allele in the pathogenesis of ACL. Nevertheless, more studies are required to elucidate the role of CCR5 in the pathogenesis of ACL.