Preliminary study on the immunogenicity of a newly developed GCC Tdap vaccine and its protection efficacy againstBordetella pertussisin a murine intranasal challenge model

Abstract

Purpose Active reduced dose tetanus-diphtheria-acellular pertussis (Tdap) vaccination for adolescents and adults is necessary because waning immunity after primary diphtheria-tetanus-pertussis vaccination is related to the recent emergence of pertussis. This study was conducted to compare the immunogenicity and protection efficacy against Bordetella pertussis between a new GCC Tdap vaccine and a commercially available Tdap vaccine in a murine model.Materials and MethodsBALB/c mice were immunized with two doses of diphtheria-tetanus-acellular pertussis (DTaP) vaccine for priming and a subsequent Tdap booster vaccination. According to the type of booster vaccine, mice were divided into four groups: commercially available Tdap vaccine in group 1 and GCC Tdap vaccines of different combinations of pertussis antigens in groups 2 to 4. Humoral and cell-mediated immune responses and protection efficacy using a murine intranasal challenge model after booster vaccination were compared among the four groups.ResultsEvery group showed significant increases in antibody titers against pertussis antigens such as pertussis toxin, filamentous hemagglutinin, and pertactin after booster vaccination. Spleen cells showed both Th1 and Th2 cell-mediated immune responses stimulated by pertussis antigens in all groups without any significant difference. In the intranasal B. pertussis infection model, bacteria were eradicated in all groups five days after challenge infection.ConclusionThis preliminary study did not show significantly different immunogenicity or protection efficacy of the new GCC Tdap vaccines compared to the commercially available Tdap vaccine, although a more extensive study is necessary to assess the differing efficacies of the new GCC Tdap vaccines.

Assessment of safety and efficacy against Bordetella pertussis of a new tetanus-reduced dose diphtheria-acellular pertussis vaccine in a murine model

“…In particular, it is essential to determine whether Tdap vaccines containing lower doses of diphtheria toxoid and pertussis antigens compared with DTaP vaccines can induce a boosting effect. We have previously reported preliminary results from a non-clinical study of the new GCC Tdap vaccine using a murine model [8]. In this study, mice received two doses of DTaP vaccine as primary vaccination followed by a single dose of Tdap vaccine as booster vaccination, a method that considered the human vaccination schedule of four doses of DTaP vaccine and one dose of Tdap vaccine [8].…”

“…We have previously reported preliminary results from a non-clinical study of the new GCC Tdap vaccine using a murine model [8]. In this study, mice received two doses of DTaP vaccine as primary vaccination followed by a single dose of Tdap vaccine as booster vaccination, a method that considered the human vaccination schedule of four doses of DTaP vaccine and one dose of Tdap vaccine [8]. Although the new Tdap vaccine showed favorable immunogenicity and protection efficacy against B. pertussis intranasal challenge, antibody titers against pertussis antigens were high even before Tdap booster vaccination, and inoculated B. pertussis was completely eradicated within 5 days of intranasal challenge [8].…”

“…In this study, mice received two doses of DTaP vaccine as primary vaccination followed by a single dose of Tdap vaccine as booster vaccination, a method that considered the human vaccination schedule of four doses of DTaP vaccine and one dose of Tdap vaccine [8]. Although the new Tdap vaccine showed favorable immunogenicity and protection efficacy against B. pertussis intranasal challenge, antibody titers against pertussis antigens were high even before Tdap booster vaccination, and inoculated B. pertussis was completely eradicated within 5 days of intranasal challenge [8]. These results are believed to be a consequence of the prolonged effect of two shots of DTaP vaccination supplementing the boosting effect of Tdap vaccination.…”

“…Such resurgence of pertussis is believed to be a consequence of waning immunity against pertussis acquired by DTaP vaccination, and therefore, a booster vaccination with a tetanus-reduced dose diphtheria-acellular pertussis (Tdap) vaccine during adolescence was introduced [6, 7]. In anticipation of a predicted Tdap vaccine shortage, the Green Cross Corporation (GCC; Yongin, Korea), a pharmaceutical company of Korea, developed a new Tdap vaccine [8]. …”

“…We previously reported the immunogenicity and protection efficacy of the newly developed GCC Tdap vaccine in a murine model in 2015, and demonstrated that the new vaccine showed comparable efficacy with a commercially available Tdap vaccine [8]. However, in the previous study, a robust antibody response was observed after two doses of primary DTaP vaccination, which prevented differentiation of the effects of the Tdap booster vaccine [8]. …”