Background and aim Despite the mass vaccinations, pertussis has recently caused large epidemics in many industrialised countries. Vaccine-induced immune responses may be impaired due to polymorphisms in genes encoding regulatory cytokines such as IL-10. The aim of this study was to evaluate the role of IL-10 promoter polymorphisms on vaccine responses after acellular pertussis booster vaccinations.

Methods Seventy-five adolescents received diphtheria-tetanus-acellular pertussis (dTap) vaccination in 1997. They were followed at 3, 5 and 10 years after. At year 10, a second booster was administrated. Antibodies (n = 52) and cell mediated immunity (CMI) (n = 38) against pertussis antigens were measured. IL-10 polymorphisms (rs1800890 and rs1800896) were detected using Sequenom iPlex Gold system.

Results After the second booster, rs1800896 was found to affect the geometric mean value (GMV) of proliferation (counts per minute, cpm) and stimulation index (SI) against pertussis antigens; pertussis toxin (PT), filamentous hemagglutinin (FHA), pertactin (PRN) (Table).

Another SNP (rs1800890) affected the CMI against PT and FHA after the booster vaccination. Also, the IgG antibody concentration against PT and PRN differed significantly between the genotypes after the original vaccination, at 3-year follow-up and before the second booster.

Conclusion These preliminary results suggest that IL-10 might play an important role in modulating both antibody and cell mediated immune responses after pertussis vaccination.