| Research Problem/Issue | The poultry sector plays a pivotal role in the economy of Pakistan, meeting the food demand for the rapidly growing population and providing employment to over 1.5 million people in the country. Current investment in this sector is over 1000 billion rupees. However, the poultry industry is more vulnerable to infectious diseases than any other enterprise in livestock. Infectious bursal disease (IBD) is one such economically important disease which infects chickens at an early stage of life (2-6 weeks). The disease is caused by infectious bursal disease virus (IBDV), and is manifested by diarrhea, trembling, anorexia, ruffled feather, and sudden death of infected birds [3]. The disease was first reported in 1971 in Pakistan, and the disease causes 70% mortality in infected chickens. Currently, IBD is endemic in Pakistan and its multiple outbreaks have been reported in the recent past.
To cope with IBD, one of the viable options is timely vaccination of chickens. However, most of the IBD vaccines such as conventional live vaccines (228E, Bar-706, IBA-VAC, INTERVAC IBD, DS Gumboro VAC), inactivated vaccines (Bigopest, Gamboriffa, Gallimune 204), and a viral vector vaccine (VAXXITEK HVT+IBD) are imported. Currently, a huge foreign exchange (equivalent to 17.8 billion PKR) is spent to procure poultry vaccines. Though, Poultry Research Institute-Karachi and Grand Pharma (Pvt.) Ltd., Islamabad, produce conventional killed and live vaccines for IBD, none of the entrepreneur in Pakistan is involved in production of modern viral vector vaccines, considered to be more effective and safer.
The main objective of the proposed project is to produce and commercialize locally-made modern viral vector vaccines for combating IBD caused by local IBDV strains. Such types of safe and efficacious viral vector vaccines that present antigenic regions from local IBDV isolates to the immune system of the host (chickens) could be developed by engineering viral vectors (such as adenoviruses) using recombinant DNA technology. The proposed research work focuses on the Knowledge Research Area “Biological Sciences”, and addresses an important problem of viral infections in poultry which are currently threatening the growth of the poultry industry in Pakistan.
We have generated a potential modern adenoviral vector vaccine candidate based on the VP2 capsid protein of a local IBDV isolate. The VP2 protein from a local IBDV strain (sequence deposited by our group in NCBI GenBank under accession number: KT281984) was selected to generate the vaccine, since variations in the capsid protein are known to influence virulence of IBDV [6,7]. Our preliminary results reveal that the vaccine candidate generates a strong immune response, and provides better protection against IBD in chickens than the commercial vaccine.
During the proposed work, various parameters (growth parameters, vaccine dose, formulation, time-point of immunization etc.) of the potential vaccine candidate will be optimized, production of the vaccine will be scaled-up, and immunization trials will be conducted at a large scale. In addition, collection of virulent field isolates will be done throughout the life of the project, and if any critical mutation(s) are found in the VP2 gene, new viral vector vaccines will be generated and tested. The research work will be performed in collaboration with NIBGE (Faisalabad), NIAB (Faisalabad), University of Agriculture (Faisalabad), NRLPD-NARC (Islamabad) and industrial counterpart (Grand Pharma (Pvt.), Ltd., Islamabad). In association with the Grand Pharma (Pvt.), Ltd., Islamabad, using the GMP facility, vaccine will be produced at large scale. Patent(s) will be filed and necessary approvals for production and commercialization will be obtained by the research team and industrial counterpart from regulatory authorities. The availability of locally-produced safe and effective IBD vaccines will save foreign exchange, and will contribute towards sustainable development of the poultry industry in Pakistan. The proposed project will also offer opportunities for employment and training of manpower in the field of vaccine development in Pakistan, and will lead to the establishment of a vaccine production platform in Pakistan that can be generalized for the production of viral vector vaccines against other infectious diseases.
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