Biotechnology 54000, September 8, 2009
Case Studies in rDNA drugs
Biotechnology 54000, September 8, 2009
Case Studies in rDNA drugs
I. Case Studies: How well do your know your Biotechnology Drugs?
Patient 1: Is a 60-year-old woman who has been rushed to the ER, complaining of pain in the center of her chest that is spreading down her shoulders, neck and arms. A team of emergency room physicians determine that the woman is suffering an Acute Myocardial Infarction (AMI; heart attack), most likely due to a blood clot in her coronary arteries. What medication would likely be administered to this woman to restore blood flow to the heart within minutes of injection? Briefly, how does this medication work?
Activase: 5 sec bolus restores blood flow within minutes,
Activase / TNKase converts plasminogen to plasmin; breaks down fibrin in clot
Patient 2: Is a 50-year-old man with Type I diabetes. He visits his physician because he is concerned about a number of small sores on his feet that do not seem to be healing well. He also saw a TV commercial on a new diabetes medicine, Byetta. He wants to discuss trying Byetta alone or in combination with the Humalog mix he currently takes. What is “Humalog Mix” and would you recommend for this patient’s two concerns?
Regranex – rPDGF – diabetic foot ulcers
Byttta – sorry, not for Type I diabetes! DTC advertising
Humalog Mix – combo of a Rapid acting + long acting 'basal' insulin
Patient 3: is undergoing chemotherapy for malignant melanoma. What are two rDNA drug options that drugs might be recommended for this patient? How are they different? Why might Aranesp and Neulasta be prescribed along with the chemotherapy regimen?
Indicated for malignamt melanoma: Proleukin, Intron A
Proleukin (r Interleukin-2 - IL-2): stimulate WBCs, T cell and natural killer (NK) cells
Intron A (r Interferon alpha-2b) Proteins produced naturally by white blood cells and fibroblasts that may work directly on cancer cells to slow their growth, or they may cause cancer cells to change into cells with more normal behavior.
Aranesp – to increase WBCs alleviating anemia associated with chemo
Neulasta – alleviating neutropenia
Patient 4: Is a 35-year old man admitted to the hospital with bacterial pneumonia. Although a course of IV antibiotics is administered, his symptoms suddenly and rapidly worsen, with loss of consciousness, systemic blood clotting, and indications of multiple organ failure presenting within 4 hours of his admittance. Given the rapid deterioration of the patient’s health, what life-threatening condition would you suspect (other than pneumonia!), and what rDNA medication would you recommend?
Severe Sepsis: an overwhelming systemic response to infection - the immune system sets off a chain reaction to fight the infection - 'walling off' toxic LPS - widespread blood clotting. symptoms occur throughout the body. As a result of this systemic response, a patient with sepsis often has a fever, and a faster than normal heart rate and breathing rate. Because “germs” may be found – sometimes refer to the condition as a “blood infection” or “blood poisoning.”
Xigris - .Activated Protein C inhibits blood coagulation, increases fibrinolysis, and controls inflammation Works IN the blood vessel wall.
Patient 5: Is a 12-year-old girl with Turner's syndrome (45,
X0). She is far shorter than her peers, a common feature of Turner's, and her
pediatrician predicts her full height will be 4 feet, 8 inches. Her parents
would like to investigate treatments that might increase the height of their
daughter while she is still growing. What two choices for medication might be
indicated for this girl, and as a pediatrician, what are some benefits and drawbacks
of this type of treatment that you might discuss with this otherwise healthy
young girl - and her concerned parents?
Humatrope: Somatropin rDNA origin - human growth hormone
July 25, 2003: FDA Approves Humatrope for Short Stature: (only the shortest 2-3% of children qualify). * Drug delivery * Cost to patients * Drug side effects * Will it be covered by insurance
Quick diagnosis! What rDNA meds would be indicated for
the following people:
Patient 6: A 50-year old man with chronic plaque psoriasis.
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Amevive (IgG/LFA-3)
Patient 7: A 9th grade girl in Indiana, before she can be allowed to enter
her freshman year in High School, 2007
===
Recombivax HB -state law since 2004
Patient 8:A man with a “central line” (central
venous access catheter) that has become occluded by a blood clot
===Cathflo Activase
Patient 9: A 40-year old patient recently diagnosed with Multiple Sclerosis
===Avonex (1 dose / week) or Betaseron
Patient 10: A healthy, 22-year old woman, not yet sexually active, who visits her physician for her annual Pap smear
===Gardasil
Patient 10b!: A 70-year old female with osteoporosis
===Forteo (rPTH)
Patients 11-16: Hmmm...what are the chances of this happening?
6 patients are all in a waiting room. One patient has been diagnosed with Malignant melanoma, one with Non-Hodgkin's lymphoma, another with Hairy cell leukemia, still another with Kaposi's sarcoma, one with Chronic hepatitis B (HBV), and a final person with Condylomata acuminata (if you don't know, don't ask!). Amazingly, they find that they are all taking the SAME medication, which is... Intron A!!!
II. Human Growth Hormone: cDNA cloning and expression in Bacteria
1. Who authored this paper? (and what does this have to do with the Midnight Raid of Peter Seeburg and Axel Ullrich?)
Martial (--> Belgium) =====$17M
Hallewell
Baxter ===$17M
Goodman (--> Harvard) ===$17M!
Nature. 1979 Oct 18; 281:544-8. Direct expression in Escherichia coli of a DNA sequence coding for human growth hormone. Goeddel DV, ..... , Seeburg PH. [Genentech]
DNA coding for human growth hormone was constructed by using chemically synthesised DNA in conjunction with enzymatically prepared cDNA. This 'hybrid' gene was expressed in Escherichia coli under the control of the lac promoter. A polypeptide was produced having the size and immunological properties characteristic of mature human growth hormone.
(Seeburg UCSF / Genentech Oct 1979 Nature cloning of hGH) Max Planck,
=== $17 M! hmmm, does that seem right!?
$200 M settlement (or "Risk Mitigation Exercise") $50 M building
2. What human tissue was source of the hGH? (and what is acromegaly?)
Fig 1: Human pituitary tumors (acromegalic tumors) = hGH most abundant protein
Fig 2: PolyA mRNA pooled to make ds cDNA = full length or nearly full length hGH cDNA that produces expected digestion products
3. Why was cDNA used rather than genomic DNA? Bacteria don't have introns!
4. Conclusions of Figures 3, 4, 5, and Figure 6?
Fig 3: 26 aa of signal peptide, 191 aas
Fig 4: Codon bias: preference for G C over A U in wobble position
Fig 5: hGH inseted into HindIII site of TrpD = to clone it in frame with TrpD, had to add 1 base - E coli would produce a fusion protein of NH2 terminal region of TrpD, the 5' UTR of hGH (~24 bp) , the 26 aa signal peptide, and ALL 191 aa's of hGH
Fig 6: Was hGH synthesized? trp operon induced - 2 proteins made Trp E and TrpD/hGH (34,000 kD) = which is IPd by hGH antibodies (6a) = 3% of total protien synthesis
III. For Visual Learners ... think fast! :)
| What is the protein product of this drug? This drug is prescribed for what indication? |
How is this drug similar to the one at left? How is is different? |
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| A fairly new drug for what indication? What is the protein product of this drug? |
Who would benefit from this drug..and what are the dangers? |
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| What are these two drugs? How do they differ? | |
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4 million Americans are infected with this disease...and this drug fights it...what disease is it? |
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| June 8, 2006: What did the FDA approve, and what are the protein products? Who will this product help? | Tagline: "Are you ready to start Chemotherapy?" ... "Be Ready" What is this drug and what does it do? |
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What is the protein product of this drug? |
Who would benefit from this drug..and why? |
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| What is the protein product of this drug? Who would receive it, and are there any dangers in this product? | What is the protein product of this drug? How is it new and improved over its older 'sibling'? |
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This drug is indicated for what condition - and what is the protein product? |
Just WHO is the YOU is Lilly taking care of...and how does it differ from the drug at right? |
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What is the protein product of this drug? |
What recombinant protein forms the basis of these 3 drugs? What is their indication? How are they similar and different? |
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| This drug is indicated for what condition - and what is the protein product? | What is the protein product of this drug? |
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IV. Mechanism of Action: A bit more detail on the Mechanism of Action (MOA) of some of the drugs:
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MOA: for the Interferons and T-cell autoimmune diseases
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MOA is unknown, but interferons act by:
*Good
website on the differences between Interferons, Interleukins and other "Biologic
Therapies" that help the immune system work better against disease.
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Abnormal dendritic cells (antigen presenting cells) show a protein called LFA-3 on their surface. The LFA-3 protein binds to the T-cell CD2 receptor, and prompting the T cells to initiate an inflammation pathway as T-cell "memory effector cells". The LFA-3 part of the fusion protein binds to the T-cell CD2 receptor (preventing the dendritic cells from binding), and the IgG1 "tail" signals NK cells to seek and destroy the T-cells...way cool! More info Because Amevive reduces T-cell counts (important for fighting off infections, etc), T-cell levels are monitored closely after treatment MOA |
Proleukin in an Interleukin 2, another immune system modulator:
IL-2 activates the immune system in several ways, but the
major one is to stimulate T cell and natural killer (NK) cell proliferation.
