(2015) for the MULTIBOOST sera or by multiplex immunoassay as published in Van Twillert et al. confidence interval are represented. Statistical analyses were performed, and significant values relative to WT strain are indicated (?? 0.01). Data_Sheet_1.DOCX (1.3M) GUID:?3C7BBCA4-07C2-426A-997E-2EF71D8EC30A FIGURE S2: Determination of antibodies binding onto B1917 (WT) and knock-out variants using convalescent samples. (A,B) Quantification of total IgG binding onto B1917 (WT) and KO variants using the 1st WHO International Standard pertussis antiserum NIBSC 06/140 (A) and 10 MW-150 dihydrochloride dihydrate convalescent (B) samples. The fluorescence intensity was decided from at least two experiments with technical duplicates for panel (A) and at least once for panel (B) and reported relative to those of the WT strain. Geometric means with 95% confidence interval are represented. Statistical analyses were performed, and significant values relative to WT strain are indicated (**** 0.0001, ??? 0.001). Data_Sheet_1.DOCX (1.3M) GUID:?3C7BBCA4-07C2-426A-997E-2EF71D8EC30A FIGURE S3: Serum bactericidal activity of post-aP vaccine samples with B1917 (WT) and KO variants deficient of vaccine candidate antigens. Serum bactericidal titers were assigned as the interpolated serum dilution which gives 50% of bacterial killing when incubating the bacteria with serial dilutions of post-aP vaccine serum and active match. 7 sera were analyzed. The geometric means with 95% confidence interval are represented. Statistical analyses MW-150 dihydrochloride dihydrate were performed for each data point using the corresponding WT data point as a control, and no significant values were decided. Data_Sheet_1.DOCX (1.3M) GUID:?3C7BBCA4-07C2-426A-997E-2EF71D8EC30A TABLE S1: Sequences of the primers used to generate knock-out mutants and pertactin complemented strain in B1917. Data_Sheet_1.DOCX (1.3M) GUID:?3C7BBCA4-07C2-426A-997E-2EF71D8EC30A Data Availability StatementAll datasets presented in this study are included in the article/Supplementary Material. Abstract Despite high vaccination protection, the causative agent of whooping cough is still a health concern worldwide. A resurgence of pertussis cases has been reported, particularly in countries using acellular vaccines with waning immunity and pathogen adaptation thought to be responsible. A better understanding of protective immune responses is needed for the development of improved vaccines. In our study, strain B1917 variants presenting a single gene deletion were generated to analyze MW-150 dihydrochloride dihydrate the role of vaccine components or candidate vaccine antigens as targets for bactericidal antibodies generated after acellular vaccination or natural infection. Our results show that acellular vaccination generates bactericidal antibodies that are only directed against pertactin. Serum bactericidal assay performed with convalescent samples show that disease induces bactericidal antibodies against Prn but against other antigen(s) as well. Four candidate vaccine antigens (CyaA, Vag8, BrkA, and TcfA) have been studied but were not targets for complement-mediated bactericidal antibodies after natural infection. We confirm that Vag8 and BrkA are involved in complement resistance and would be targeted by blocking antibodies. Our study suggests that the emergence and the common blood circulation of Prn-deficient strains is usually driven by acellular vaccination and the generation of bactericidal antibodies targeting Prn. Keywords: vaccines were introduced and considerably reduced the incidence of the disease. wP vaccines were then replaced in many countries by less reactogenic acellular (aP) vaccines, composed of one to five purified and detoxified antigens from your bacterium (pertussis toxin, filamentous hemagglutinin, pertactin and fimbriae 2 and 3) (Gustafsson et al., 1996). In the last two decades, the incidence of pertussis has been increasing in several countries which have high aP vaccine protection (Nieves and Heininger, 2016; Pinto and Merkel, 2017; Esposito et al., 2019). This is likely to be caused by a quantity of factors including a shorter period of Adamts5 protection provided by aP than wP vaccines (Witt et al., 2013; Klein et al., 2016), a greater blood circulation of in aP-vaccinated populations (Althouse and Scarpino, 2015) and development MW-150 dihydrochloride dihydrate of strains with greater fitness (Belcher and Preston, 2015). Mechanisms involved in pathogen adaptation include allelic and antigenic variations, emergence of strains with increased pertussis toxin production or strains deficient in Prn, PTX or FHA (Bart et al., 2014a; Bouchez et al., 2015; Xu et al., 2015; Williams et al., 2016; Weigand.