ENGR / BRAE 213 – Bioengineering Fundamentals

Biotechnology

Case Study- Duchenne Muscular Dystrophy (DMD)

Dystrophin gene

Case Study- Duchenne Muscular Dystrophy (DMD)M

uscle fiber

Dystrophin gene

Case Study- Duchenne Muscular Dystrophy (DMD)M

uscle fiber

Dystrophin gene

Case Study- Duchenne Muscular Dystrophy (DMD)

Case Study- Duchenne Muscular Dystrophy (DMD)

Genomics

• How do we know patient has mutation?– Sequencing– PCR

Genomics- Background

“expressed gene”

DNA makes up genome

Mutations (single nucleotide polymorphism)

• Different nucleotides in DNA/RNA can lead to different amino acids in protein

Person 1

Person 2

Genomics Technology- PCR

• Polymerase Chain Reaction – amplify DNA

Genomics Technology- PCR

• http://highered.mcgraw-hill.com/olc/dl/120078/micro15.swf

• Produce specificity with primers– 1 primer set for normal DNA– 1 primer set to recognize mutated region

Genomics Technology- PCR

Genomics Technology- Sequencing

• Step 1 – amplify target sequence– dideoxynucleotides (ddNTPs) stop replication by

polymerase

• Step 2- electrophoresis of products

Genomics Technology- Sequencing

Genomics Technology- Sequencing

Genomics

• Sequencing explained:– http://youtu.be/bEFLBf5WEtc

• Using PCR or sequencing- can identify mutations in the patients’ genome and use that information to inform treatment

Pharmacological Therapy

Symptom

Anti-inflammatorysteroidInflammation

Gene Therapy

• Bioengineering as practical application of biological science– Use genes themselves to directly treat

patients

Fiber Death

InflammationFiber Regeneration

Cause

Gene Therapy

• Naked DNA

• Virus containing DNA

• Liposome containing DNA– Lipid bilayer

• Naked DNA + simple, safe, efficient uptake into cell

– poor incorporation into genome, tissue specific

• Virus containing DNA+ efficient uptake & incorporation, specific

– immune rejection, inflammation

• Liposome containing DNA+ efficient uptake

– non-specific, poor incorporation intogenome

Gene Therapy

FIRST U.S. TRIAL OF DMD GENE THERAPY UNDER WAYCOLUMBUS, Ohio, March 29, 2006 — The first U.S. human gene therapy trial directed at Duchenne muscular dystrophy (DMD) was launched yesterday at Columbus (Ohio) Children’s Hospital, the Muscular Dystrophy Association (MDA), Children’s Hospital, and Asklepios Biopharmaceutical Inc. (AskBio) announced today.

DMD research study halted?

Activity

Which delivery method would be preferable for treat the intestine?

A. Naked DNA

B. Virus containing DNA

C. Liposome containing DNA

Which delivery method would be preferable for treat the

intestine?

A. Naked DNA

B. Virus containing DNA

C. Liposome containing DNA

Activity

Which delivery method would be preferable for delivery to the retina?

A. Naked DNA

B. Virus containing DNA

C. Liposome containing DNA

Which delivery method would be preferable for delivery to the

retina?

A. Naked DNA

B. Virus containing DNA

C. Liposome containing DNA

Protein Therapy

Liam Hoekstra – Super Boy? - link

Protein Therapy

• Fiber regeneration ≈ fiber enlargement

Cloned myostatin gene to obtain sequence

Used sequence information to delete myostatin gene from genome in mice

Fiber Death

InflammationFiber Regeneration

Limited

by myostatin

Fiber Death

InflammationFiber Regeneration

Limited

by myostatin

Protein Therapy

• Myostatin antibody to block protein from functioning

Str

engt

h

Protein Therapy

• Myostatin antibody to block protein from functioning

Question:

If you were a DMD patient, what would be your preferred form of treatment?

A. Dystrophin gene therapy

B. Myostatin antibody therapy

C. Prednisone (anti-inflammatory)

D. Physical therapy