Developing the captured antigen presentation system as a vaccine against bovine tuberculosis
Bovine tuberculosis is a devastating disease of cattle responsible for major economic losses in Africa and Asia. This disease infects more than 50 million cattle every year, costing US$3 billion annually. The bulk of these losses are in low and middle-income countries. The disease leads to poor agricultural productivity, hinders trade in livestock and livestock products, and can also infect humans who come into contact with unpasteurized products from infected animals. As such, development of an effective vaccine would not only answer to the challenges of constrained livestock production, but it would also protect human life among smallholder farmers and their communities.
There are currently no licensed vaccines against bovine tuberculosis. Attempts to develop vaccines have relied either on using the human live attenuated causative bacteria of a strain known as bacille Calmette Guérin (BCG), which lacks expression of several potential vaccine antigens; or attempts have depended on the discovery of effective mycobacterial antigens for use as subunit vaccines. To date, no tuberculosis vaccines have been reported to possess better protection than that offered by the BCG vaccine for human use.
This project offers an opportunity to develop a new vaccine by using a new vaccination platform developed by the Wyss Institute. It is based on a captured antigen presentation system (CAPS) comprising two technologies: (1) an artificial lymph node containing a self-assembling scaffold matrix of silica with some components that attract and activate host cells to foreign antigens that become trapped in the artificial lymph node matrix; and (2) magnetic opsonin technology, where cell wall components called pathogen associated molecular patterns — derived from bacteria or recombinant antigens — are captured using specially coated magnetic beads. Wyss has demonstrated the efficacy of both technologies in mice with a range of pathogens. The project is a collaboration between Wyss Institute at Harvard University and AgResearch Limited (New Zealand).
This project is funded through the Livestock Vaccine Innovation Fund (LVIF), a partnership between the Bill and Melinda Gates Foundation, Global Affairs Canada, and IDRC. It represents a joint investment of CA$57 million over five years to support the development, production, and commercialization of innovative vaccines against priority livestock diseases in sub-Saharan Africa, South Asia, and Southeast Asia.