Comparison of IgG antibody levels, avidity, and subclass distribution against pertussis toxin in children and adolescents after four-dose primary whole-cell (DTwP) or acellular (DTaP) vaccination, each followed by a single DTaP booster.

Vaccination plays a key role in the prevention of pertussis, the infectious disease that is endemic worldwide. Two types of pertussis vaccines are currently in use: whole-cell (wP) and acellular (aP) vaccines. Differences in the duration of immunity have been observed depending on the vaccine type. In this study, the levels of individual IgG subclasses and antibody avidity were assessed in children vaccinated with either aP or wP vaccines. The results revealed no significant differences in the mean IgG antibody levels and avidity between children immunised with wP and those who received aP vaccines. However, in the vaccinated children IgG4 was a dominated IgG subclass, regardless of vaccine used (aP v. wP), whereas in pertussis patients the IgG1 was dominating. These findings need deeper investigation, in terms of a vaccine efficacy and wanning immunity, as typically in response to protein antigens IgG1 is dominating. Moreover, the observation of IgG4 predominance in vaccinated vs. IgG1 predominance in infected individuals might be a valuable parameter in pertussis diagnostics as it enables differentiation between infected and vaccinated but not-infected individuals.