1. Chapter 7: Animal Biotechnology
Introduction to Biotechnology
Fall 2008

2. Figure 7.2a

3. B1 B2 B3 B4

5. What are some of the animals…
Mice
Rats
Zebrafish (3 month generation time, 200 progeny, complete embryogenesis in 120 hrs)
Dogs (lungs and cardiovascular system)
Cats
Pigs (PPL Therapeutics- delete a gene which causes hyperacute rejection of pig-to-human organ transplantation)
Primates (HIV and AIDs research, geriatric research)

6. Alternatives to Animal Models
(figure 7.5) Cell culture devices
Researchers use cell cultures and computer-generated models whenever possible, but this doesn’t work for looking at an organ or entire animal

7. Figure 7.5

8. Regulation of Animal Research
The “Three Rs”
Reduce the number of higher species (cats, dogs, primates) used
Replace animals with alternative models whenever possible
Refine tests and experiments to ensure the most humane conditions possible

9. Veterinary Medicine as Clinical Trials
Treatments for humans may also be useful for treatments with animals (e.g. the BRCA1 gene found in 65% of human breast tumors is similar to the BRCA1 gene in dogs)
Hyperthermia + radiation = more effective at killing tumors
Stimulation of cytokines for curing skin cancers

10. Bioengineering Mosquitoes to Prevent Malaria
Cloned in a gene that prevents the parasite from traversing the midgut; blocking the continuation of its life cycle
Developed an antibody that prevents the parasite from entering the mosquito’s salivary gland

11. Clones Start with Embryo Twinning (splitting embryos in half)
Cloning (figure 7.7)
Creating Dolly
Limits to Cloning: The donor cell must come from a living organism
An organism is also shaped by its environment
The success rate for cloning is very low
Clones may be old before their time
The future of cloning: preservation of endangered animals, studying the effect of drugs etc on duplicates, improve agricultural production

12. Figure 7.7

13. Transgenic Animals Retrovirus-mediated transgenesis
Pronuclear microinjection (figure 7.8)
Embronyic stem cell method
Sperm-mediated transfer

14. Figure 7.8

15. Improving Agricultural Products with Transgenics
Faster growth rates or leaner growth patterns (improve the product), more product
Increase nutritional content-lactoferrin
Turning the animals into efficient grazers
Transfer antimicrobial genes to farm animals

16. Knock-outs: A Special Case of Transgenesis
A specific gene is disrupted or removed such that it is not expressed (Figure 7.11)
Procedure: DNA is modified, it is added to embryonic stem cells, where it undergoes homologous recombination. The modified ES cells are then introduced into normal embryo. The embryo is implanted in an incubator mother. The offspring is a chimera. It may take several generations of crossbreeding are required to produce animals that are complete knock-outs.
Breast cancer mouse

17. Figure 7.11

19. Transgenic Animals as Bioreactors
Biosteel otherwise known as spider silk, cloned into goat milk (“silkmilk” goats)
Goats reproduce faster than cows and are cheaper than cows
Hens also make good bioreactors in that they are cheap and a lot of eggs are produced at one time

20. Producing Human Antibodies in Animals
1980’s Concept of the “magic bullet”
Figure 7.12: Production of Mabs
Used to treat cancer, heart disease, and transplant rejection
HUMANIZED monoclonal antibodies were developed to prevent the human anti-mouse antibody (HAMA) response

21. Figure 7.12