Development of a novel vaccine for contagious caprine pleuropneumonia based on a fast-growing Mycoplasma feriruminatoris chassis

Contagious caprine pleuropneumonia (CCPP) is a severe respiratory disease of goats and sheep caused by the bacterium mycoplasma capricolum subsp capripneumoniae (Mccp). Clinical CCPP occurrence has been reported in 40 countries in Africa and Asia and mortality and morbidity can reach 70% and 100% respectively within 7-10 days. Goats and sheep are an important source of income for women and CCPP severely affects their ability to provide for their families. The Global Alliance for Livestock Veterinary Medicines estimates that every year, CCPP causes economic losses of up to USD$507 million (approximately CA$484 million) in endemic areas.

Vaccination remains the most effective and affordable method to control CCPP, because antibiotic treatment does not eliminate the bacterium and sanitary measures are not feasible in smallholder settings. The current CCPP vaccine is safe but its protection is short-lived (less than one year). It is also expensive to produce because the bacterium grows slowly and results in low yields.

The objective of this project is to develop a novel CCPP vaccine based on the fastest-growing mycoplasma species to date, mycoplasma feriruminatoris (M.feri). M. feri was isolated from wild goats and has a generation time of less than 30 minutes. M. feri genes encoding virulent factors will be deleted, creating space for insertion of Mccp genes that encode known and predicted vaccine candidate antigens. Goats will be vaccinated with the inactivated or live new recombinant vaccine, then experimentally infected with Mccp to determine whether the vaccine is protective. This project will use cutting-edge synthetic biology tools to construct a vaccine for CCPP that will grow efficiently, express protective Mccp antigens, and be used either as a live or inactivated vaccine.

This 24-month project is a collaboration between the University of Bern in Switzerland, the Institut national de la recherche agronomique at the University of Bordeaux, France, and the J. Craig Venter Institute in the USA.