Kunitz-type protease inhibitor as a vaccine candidate against schistosomiasis mansoni. (January 2018)

• Record Type: Journal Article
• Authors: Ranasinghe, Shiwanthi L.; Duke, Mary; Harvie, Marina; McManus, Donald P.
• Is Part Of: International journal of infectious diseases. Volume 66(2018)
• Page Start: 26
• Page End: 32
• Publication Date: 2018-01
• Subjects: Kunitz protein -- Schistosomiasis mansoni -- SmKI-1 -- ES products; Communicable diseases -- Periodicals; Communicable Diseases -- Periodicals; Communicable diseases; Periodicals; Electronic journals; 616.9
• DOI: 10.1016/j.ijid.2017.10.024
• Languages: English
• ISSNs: 1201-9712

Abstract

Graphical abstract: Highlights: The vaccination of mice with rSmKI-1 resulted in reduced numbers of parasites and eggs. The rSmKI-1 vaccine produced a solid IgG response, with the IgG1 isotype being predominant. The rSmKI-1 vaccine down-regulated the Th2 immune response, reducing disease pathology. SmKI-1 has potential for development as part of a schistosomiasis cocktail vaccine. Abstract: Objective: The aim of this study was to develop a vaccine against schistosomiasis, which is a major challenge due to the complex lifecycle of the causative schistosome parasite. Methods: SmKI-1 is a 16-kDa Kunitz-type protease inhibitor present in the excretory–secretory products and tegument of adult worms and eggs of Schistosoma mansoni . Two independent vaccine trials were performed in mice to determine the efficacy of rSmKI-1 in developing protective immunity. Results: The results obtained showed reductions of 23–33% in adult worms, 28–31% in intestinal eggs, 33–39% in faecal eggs, and 20–43% in liver eggs. Furthermore, rSmKI-1 significantly increased the production of interferon gamma, interleukin (IL)-10, and IL-6 in vaccinated mice, maintaining a Th1/Th2-type balanced protective response. Conclusions: rSmKI-1 generated partial protection against schistosomiasis mansoni in the murine model of infection and could be developed as part of a combination vaccine with other vaccine candidates to provide an even more solid level of protection.