A high seroprevalence of antibodies to pertussis toxin among Japanese adults: Qualitative and quantitative analyses

by Takumi Moriuchi, Nao Otsuka, Yukihiro Hiramatsu, Keigo Shibayama, Kazunari Kamachi In 2013, national serosurveillance detected a high seroprevalence of antibodies to pertussis toxin (PT) fromBordetella pertussis among Japanese adults. Thus, we aimed to determine the cause(s) of this high seroprevalence, and analyzed the titers of antibodies to PT and filamentous hemagglutinin (FHA) among adults (35 –44 years old), young children (4–7 years old), and older children (10–14 years old). Our quantitative analyses revealed that adults had higher seroprevalences of anti-PT IgG and PT-neutralizing antibodies, and similar titers of anti-FHA IgG, compared to the young and older children. Positive correlations were observed between the titers of PT-neutralizing antibodies and anti-PT IgG in all age groups (rs values of 0.326 –0.522), although the correlation tended to decrease with age. The ratio of PT-neutralizing antibodies to anti-PT IgG was significantly different when we compared the serum and purified IgG fractions among adults (p = 0.016), although this result was not observed among young and older children. Thus, it appears that some adults had non-IgG immunoglobulins to PT. Our analyses also revealed that adults had high-avidity anti-PT IgG (avidity index: 63.5%, similar results were observed among the children); however, the adults had lower-avidity anti-FHA IgG (37.9%,p
Source: PLoS One - Category: Biomedical Science Authors: Source Type: research