Subcutaneous administration of a fusion protein composed of pertussis toxin and filamentous hemagglutinin from Bordetella pertussis induces mucosal and systemic immune responses

Objective(s): After decades of containment, pertussis disease, caused by Bordetella pertussis seems to be re-emerging and still remains a major cause of reported vaccine-preventable deaths worldwide. The current licensed whole-cell vaccines display reactogenicity while acellular vaccines are expensive and do not induce Th۱-type immune responses that are required for optimum protection against the disease. Thus, there is an urgent need to develop new vaccines and the recombinant technology seems to be the method of choice for this purpose. The present study was an attempt to develop a new, simplified, cost-effective and well-defined vaccine against Bordetella pertussis, with capacity to induce a Th۱ response. Materials and Methods: A fusion DNA fragment encoding the N-terminal region of pertussis toxin S۱ subunit and filamentous hemagglutinin type ۱ immunodominant domain was constructed and the corresponding fusion protein (F۱S۱) was produced in Escherichia coli. F۱S۱ in conjunction with imiquimod was administered by subcutaneous (SC) and intranasal (IN) routes to BALB/c mice. Results: This vaccine formulation could elicit high levels of IFN-γ, serum IgG (with higher IgG۲a/IgG۱ ratio) and lung IgA after the SC and, to a lesser extent, following the IN administration.  Conclusion: Our results indicate that the above-mentioned important proteins of B. pertussis could be successfully produced in E. coli as a single fusion protein. Furthermore, this protein could induce proper systemic and mucosal immune responses after administration via SC or IN routes.

کلیدواژه ها:

Bordetella ، Filamentous hemagglutinin ، Imiquimod ، Pertussis ، Pertussis toxin ، Recombinant