Collaboration to Advance Vaccine Control of East Coast Fever (Theileria Parva)
Animal Diseases Research
2013 Annual Report
1a.Objectives (from AD-416):
Develop a sustainable, safe and efficacious vaccine for Theileria parva.
1b.Approach (from AD-416):
The goal is to develop an effective vaccine that controls East Coast fever (ECF) in a context suitable to sub-Saharan Africa (SSA). The current five-year project aims to increase the productivity of cattle in SAA through research that leads to the development of modern day vaccines for the control of ECF, a lethal disease of cattle. It directly contributes to meeting the goals of CRP3.7, the CGIAR Research Program (CRP) titled “More meat, milk and fish - by and for the poor” within the sub-component “Dairy value chain in Tanzania”. Two immune responses that contribute to immunity to ECF have been defined; an antibody response directed against T. parva sporozoites (the infective stage of the parasite) and a cytotoxic T lymphocyte (CTL) response restricted by major histocompatibility complex (MHC) class I molecules directed against T. parva schizont infected host cells. The ITM live vaccine induces the latter immunity. Thus, antigens that are the targets of these immune responses form the basis for inclusion in a novel vaccine. A product profile for a subunit vaccine against ECF (1) Recombinant schizont antigen(s) plus-minus sporozoite antigen; (2) Commercially-available delivery/production systems, expression systems, vectors, adjuvants etc.; (3) Stable at 4 degrees centigrade for 2+ years; (4) 95% protection against LD100 challenge in the laboratory; (5) Initial vaccination at one month, and (6) 2 vaccinations plus booster at 1-3 years.
This report documents research conducted under a Specific Cooperative Agreement between ARS and the International Livestock Research Institute, Nairobi. Additional details for the research can be found in the report for the parent project 5348-32000-034-00D, “Pharmacological and Immunologic Interventions against vector-borne bovine and equine babesiosis (theileriosis)”. This work relates to objective 1 of the parent project in supporting efforts to control bovine babesiosis and its tick vector through the identification of novel targets and development of new vaccine strategies. The parasite Theileria parva causes economic devastation to small holder farmers in Africa. This collaboration is to develop a economically stable and environmentally safe vaccine for the disease causes by T. parva, East Coast Fever. These studies also contribute to our efforts to develop sustainable vaccines for cattle parasites which threaten U. S. cattle and Theileria equi, an exotic infection which has re-emerged in the U.S. horses. The collaboration developed an international consortium which applied for a grant to the Bill and Melinda Gates Foundation to extend our efforts. We were recently notified that this grant was funded and will begin 1 October 2013. Also, a veterinarian in our Pathways Program completed the preliminary examination for PhD. The PhD proposal was a major component of the funded Bill and Melinda Gates foundation grant. We also received from APHIS a permit to work on East Coast Fever in our Pullman ARS laboratories. This is the first permit issued to conduct such work in the United States.