Topic 8 - Biotechnology in animal & human health

Question 1

Applications of biotechnology towards animal health… advantages…

Answer 1

Monoclonal antibodies for diagnosis

Recombinant vaccines - pros: no organism, large no. of Ag’s, cheap, eliminates other tests, improved stability

Question 2

ab & PCR tests for many diseases…Eg’s in companion animals & livestock

Answer 2

Companion: heartworm, leukaemia
Livestock: brucellosis, swine fever, mastitis, F&M, equine infectious anaemia
Poultry: avian influenza virus, samonellosis

Question 3

What are the 5 diseases worthy of note in animal health & biotech?

Answer 3

• F&M
• Mad cow disease (BSE)/Scrapie (sheep & goats)
• Coccidiosis
• Trypanosomiasis
• Theileriosis

Question 4

A bit about F&M…

Answer 4

• highly contagious
• infects cattle, sheep, goats, pigs, elephants, rodents
• 2001 UK outbreak -> 1000’s animals culled
  50% die (myocarditis)
  NOT ZOONOTIC
  vax not effective (4-6 months)

Question 5

A bit about mad cow (BSE)…

Answer 5

bovine spongiform encephalopathy (BSE)/scrapie (sheep & goats)

• chronic neuro degenerative disease in older cattle due to abnormally folded proteins (prion version of PrP)
• 1986 1st diagnosed UK
• > cows eating self

Question 6

What are prions?

Answer 6

Rogue proteins suspected of causing BSE, Creutzfeldt-Jakob disease and other neuro wasting diseases
Abnormally folded proteins -> touch & convert normal proteins -> abnormal proteins -> brain clogged with abnormal PrP proteins that are not broken down

Question 7

Prion protein molecule (produced by PRNP gene) has how many AAs? Codons?

Answer 7

254 amino acids
4 codons (136, 141, 154, 171)

Question 8

Major determinant of scrapie susceptibility? ratio…

Answer 8

Codon 171 - glutamine, arginine, histidine, lysine

4:4:1

Question 9

A bit about coccidiosis…

Answer 9

9 parisitic protozoan spp.
invades intestinal epithelial cells of cattle, sheep, poultry
- faecal contamination - overcrowding
- 20% die
- metronidazole
- vax's being tested

Question 10

Trypanosomiasis…

Answer 10

African sleeping sickness
- most studied parasites
- 16 million cattle, humans, pigs... susceptible 
- Tsete fly - vector
Continually change surface antigens
prevention via dips
possible vax's

Question 11

Theileriosis…

Answer 11

East Coast Fever
tickborne protozoan parasite…
120 ,illion per annum
death in a month

Question 12

Describe virotherapy… Which types are present?

Answer 12

anticancer treatments
engineered by altering surface proteins -> bind to different cell types (tumour cells)
1. Transduction or targeting infect & kill tumour cells
2. Transcriptional targeting - tumour specific promoter
-> to make tumour cells more susceptible to chemo
-> tagged with fluorescence to diagnose tumours

Question 13

Stem cells…

Answer 13

many cell types
bone marrow, red/white -> liver/kidney cells
Embryonic stem cells
- 32 cell embryo (controversial) Bush halted, Obama repealed ban
- to repair/replace damaged tissue or deliver proteins

Question 14

Stem cell eg.’s

Answer 14

Parkinson’s disease when dopamine neurons die, drugs increase dopamine levels

Question 15

Foetal stem cells…

Answer 15

Foetal stem cells
- brain tissue, dopamine prod.
Umbilical cord blood stem cells
- stored in case in need of stem cells eg. bone marrow transplant
Adult stem cells
- Bone marrow, leukaemia
- kill bone marrow & transplant new marrow

Question 16

SCNT & therapeutic cloning…process…

Answer 16

Somatic cell nuclear transfer
- adult nucleus put into egg with nucleus removed -> nucleus from patient inserted -> fertilised -> morula -> blastocyst -> remove ICM -> pluripotent stem cells -> (skin, nerve, pancreatic cells) -> transplanted back into patient
Controversial, ethically questionable
Vaccines
- many diseases anthrax
- SARS
- Ag only vax's safer (hep B vaccine)

Question 17

Tissue engineering…Pros, cons…

Answer 17

prod. of tissues or organs for replacement
- kidney dialysis
- organ transplant, heart pacemakers
- incentive as replacement organs $$ or not enough AND organ or tissue failure common

Question 18

Xenotransplantation…which animal best hope?

Answer 18

transplanting organs from animals -> humans
pigs best hope to reduce antigenicity, same size as humans
ethical issues chimp heart into human (1984)

Question 19

Humanising pigs…PERV…

Answer 19

Porcine endogenous retrovirus - similar to HIV
Biotech company cloned pig 2000 -> transgenic & KO 2001 -> lacked GP gene (strongly antigenic) -> cloned pigs did not carry PERV