Source: Phycotransgenics, L.L.C. submitted to NRP
DEVELOPMENT OF A MICROALGAL-BASED ORAL VACCINE DELIVERY SYSTEM FOR POULTRY
Sponsoring Institution
National Institute of Food and Agriculture
Project Status
COMPLETE
Funding Source
SMALL BUSINESS GRANT
Reporting Frequency
Annual
Accession No.
0196254
Grant No.
2003-33610-13036
Cumulative Award Amt.
(N/A)
Proposal No.
2003-00192
Multistate No.
(N/A)
Project Start Date
May 15, 2003
Project End Date
May 14, 2005
Grant Year
2003
Program Code
[8.3]- (N/A)
Recipient Organization
Phycotransgenics, L.L.C.
(N/A)
Bloomington,IN 47401
Performing Department
(N/A)
Non Technical Summary
The impetus to raise wholesome food products with limited use of antimicrobial agents has provided new challenges to poultry producers. Intensive production is a main feature that contributes to the productivity and efficiency of the poultry industry. A consequence of intensive production is the increased risk of the spread of infectious diseases. Respiratory diseases are a major cause of mortality and approximately 90% of all the condemnations in chickens are due to airsaculitis and septicemia. Producers and poultry health specialists have continually rated respiratory diseases as the most economically significant group of poultry diseases. Infectious bursal disease virus (IBDV) attacks the bursa of Fabricius of young chickens resulting in bursal lymphocytolysis and immunosuppression. Vaccination, is effective but costly, and is the primary means for controlling infectious bursal disease in the poultry industry. We anticipate that our microalgal oral vaccine delivery system will provide an economical method of delivering vaccines in poultry operations. This will result in healthier animals, thus a better and less costly product for the producer and consumer. Our technology will also reduce the amount of antibiotics used thus reducing the potential for developing antibiotic resistance. Completion of this SBIR Phase 1 research will also provide the guidelines for testing vaccines against other poultry pathogens. The net effect will be the development of a novel, efficient and effective tool for the sustainable management of disease in commercial animal operations.
Animal Health Component
100%
Research Effort Categories
Basic
(N/A)
Applied
100%
Developmental
(N/A)
Classification

Knowledge Area (KA)Subject of Investigation (SOI)Field of Science (FOS)Percent
3112150104070%
3113299116030%
Knowledge Area
311 - Animal Diseases;

Subject Of Investigation
3299 - Poultry, general/other; 2150 - Aquatic plants;

Field Of Science
1040 - Molecular biology; 1160 - Pathology;
Goals / Objectives
The goal of this SBIR Phase 1 research proposal is to determine if an immunogen expressed in microalgae delivered to chickens in drinking water and/or feed can elicit an immune response against IBDV. Completion of the research objectives will provide a model for investigating delivery of other vaccines to poultry using the microalgal system.
Project Methods
Our plan is to develop economical oral vaccines for the prevention of diseases in poultry.

Progress 05/15/03 to 05/14/05

Outputs
The specific research objectives of our USDA SBIR Phase 1 Research Program were to: a) Transform the chloroplast and nuclear genomes of Chlamydomonas reinhardtii with the VP2 gene from the classical and variant IBDV pathogen; b) Confirm and quantify the level of expression of the IBDV immunogen in Chlamydomonas, and; c) Demonstrate the induction of an antigen-specific immune response to the classical and variant VP2 in chickens treated orally with the transgenic microalgae. Transgenic algae putatively expressing the IBDV-VP2 gene with and without the FLAG epitope have been confirmed by PCR and western blot analysis. The level of protein expression was approximately 0.2 to 0.6 percent using the anti- FLAG antibody. However we had difficulty detecting the level of protein expression with the VP2 antigen. Putative transgenic algae (expressing VP2 protein of IBDV) did not induce humoral and cellular immunity and did not prevent bursal damage from challenge by IBDV. Priming chickens with one dose of DNA plasmid (carrying large segment gene of IBDV) followed by boosting chickens with transgenic algae could trigger humoral and cellular immune responses and prevent bursal damage by IBDV at 3 days after challenge. We believe these results are significant for the following reasons: 1) High levels of protective immunity are achieved with the IBDV DNA vaccine only when it is administered three times: an initial immunization and two subsequent booster immunizations. We were able to achieve a similar level when a single DNA vaccination was followed by booster immunizations with the transgenic algae putatively expressing the VP2 protein. This demonstrates that the transgenic algae can be used for oral delivery of an antigen to poultry. 2) These results indicate that the transgenic algae oral delivery system has utility for booster immunizations and may be compatible with other delivery systems such as ova injection. 3) The challenge results were conducted with a transgenic algal strain with levels of VP2 protein expression much lower than those reported above.

Impacts
Trangengic microalgae do have potential for delivery of a vaccine to poultry. However, higher levels of expression and a more efficient method of administration are needed to make the vaccines commercially successful. Currently, the use of the transgenic algae for booster vaccinations in combination with other vaccines used for primary vaccinations offers the most potential for commecial application.

Publications

  • No publications reported this period