Study on Toxicity Reduction and Potency Induction in Whole-cell Pertussis Vaccine by Developing a New Optimal Inactivation Condition Processed on Bordetella pertussis

Abstract

BackgroundWhooping cough is caused by Bordetella pertussis, and it remains a public health concern. Whole-cell pertussis vaccines have been commonly employed for expanded immunization. There is no doubt of the efficacy of whole cell pertussis vaccine, but it is necessary to improve the vaccine to decrease its toxicity.ObjectivesIn this study, an inactivation process of dealing with pertussis bacteria is optimized in order to decrease the bacteria content in human doses of vaccines and reduce the vaccine’s toxicity.Materials and MethodsThe bacterial suspensions of pertussis strains 509 and 134 were divided into 21 sample parts from F1 to F21 and inactivated under different conditions. The inactivated suspensions of both strains were tested for opacity, non-viability, agglutination, purity, and sterility; the same formulation samples that passed quality tests were then pooled together. The pool of inactivated suspensions were analyzed for sterility, agglutination, opacity, specific toxicity, and potency.ResultsThe harvest of both bacterial strains showed purity. The opacity of various samples were lost under different treatment conditions by heat from 8% to 12%, formaldehyde 6% to 8%, glutaraldehyde 6% to 8%, and thimerosal 5% to 8%. Tests on suspensions after inactivation and on pooled suspensions showed inactivation conditions not degraded agglutinins of both strains. The samples of F2, F4, F8, F12, F15, and F17 passed the toxicity test. The potency (ED50) of these samples showed following order F17 > F12 > F8 > F15, F4 > F2, and F17 revealed higher potency compared to other formulations.ConclusionsIt can be concluded that F17 showed desirable outcomes in the toxicity test and good immunogenicity with a low bacterial number content. Consequently, lower adverse effects and good immunogenicity are foreseeable for vaccine preparation with this method.

Evaluating the Compatibility of New Recombinant Protein Antigens (Trivalent NRRV) with a Mock Pentavalent Combination Vaccine Containing Whole-Cell Pertussis: Analytical and Formulation Challenges

“…As summarized in the introduction, traditional wP bulks contain TH, which is added in the process together with heat for the inactivation of wP bacteria [ 41 ]. Since TH is known to negatively affect the antigenicity and immunogenicity of IPV antigens [ 42 ], the production of TH-free wP bulks has been a focus of many DCVMs in order to add IPV antigens to the pentavalent pediatric vaccine [ 43 ]. Although there are currently no WHO-prequalified hexavalent vaccines containing both wP and t-IPV available for global use, a few locally approved hexavalent vaccines (i.e., DTwP-Hib-Hep B-IPV) prepared by Indian manufacturers are available, namely, EasySix TM (Panacea Biotec (New Delhi, India)), Shan6 ® (Sanofi Healthcare), and HEXASIIL ® (Serum Institute of India Pvt.…”

Pertussis vaccines and the role of <I>Bordetella pertussis</I> lipooligosaccharide in the immune response to pertussis infection and vaccination

“…Одна из возможностей понижения реактогенности ЦКВ заключается в уменьшении количества коклюшных клеток в дозе вакцины. С этой целью проводят оптимизацию процесса инактивации бактерий B. pertussis [70]. Ранее Р. П. Чуприниной с соавт.…”