Background: Interleukin (IL)-8 plays important roles in the recruitment and activation of immune cells during visceral leishmaniasis (VL). Genetic variations in IL-8 modulate the expression of IL-8 protein and may be associated with VL. This study aimed to evaluate polymorphisms at the IL-8 -251 position in VL patients.
Methods: This cross-sectional study was performed on three groups: Leishmania-seropositive patients with clinical symptoms of VL (n = 91), seropositive patients without clinical symptoms (n = 104), and healthy controls (n = 110). Polymorphisms at the IL-8-251 position were analyzed using allele-specific polymerase chain reaction (PCR). Anti-Leishmania antibody titers were assessed by immunofluorescence.
Results: IL-8-251 polymorphism was significantly associated with VL (P<0.002). The IL-8-251 T/T genotype was significantly higher in group 1 than in groups 2 and 3 (P<0.002). The validity of the data was analyzed using Hardy-Weinberg equilibrium and one-way analysis of variance (ANOVA), as well as χ2 tests.
Conclusions: IL-8-251 polymorphism was significantly associated with impaired immune responses in VL and might be considered a risk factor for disease development.
Keywords: IL-8; Polymorphism; Visceral leishmaniasis.