Effects of Recombinant Human Growth Hormone on the Onset ...
Human Growth Hormone CHEE450 By Leslie Davis. Human Growth Hormone Simulates linear growth in humans...
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Transcript of Human Growth Hormone CHEE450 By Leslie Davis. Human Growth Hormone Simulates linear growth in humans...
Human Growth Hormone
Simulates linear growth in humansEffects on the growth plates of the long
bones Increased cell growth Increased protein, carbohydrate and lipid
metabolism
Human Growth Hormone
Generally used to treat those with GH-deficiencies
Beneficial effects: burns, bone fractures and Turner’s syndrome Shown promise in treating chemotherapy and
AIDSIncreases body mass
Human Growth Hormone
Polypeptide 191 amino acid residuesMW = 22125 daltonsHighly hydrophobic proteins
Historical Perspective
Isolated hGH in human pituitary 1956Proof of effectiveness 1958Obtained from human pituitary gland only
Urgent need to obtain human pituitary glands at autopsy
High cost
Cloned from human gene in 1980s
Recombinant DNA Synthesis of hGH
Cloning of human DNAAdapting of the cloned gene for
expression in Escherichia coli E. coli did not have the biochemical
machinery 84 base pairs of ds DNA synthesized for direct
expression
How it works
Chemical messenger produced by the pituitary gland
Promotes growth during childhood
Plays important metabolic role throughout adulthood
Pituitary Gland
Production Process
Fermentation Highly reproducible Intracellular E. coli W3110 with a pB322-derived plasmid
coding Antibiotic resistance of genetically modified E.
coli strain Typically tetracycline and ampicillin resistant
Production Process
Glucose and mineral salt mediumExponentially growing cells in batch mode
Transferred from seed fermentor to production bioreactor
10% of final volume
High cell density fermentation
Production Process
Fed-batch bioreactor Glucose feed ~ 500-600 g/L May use peptone for amino acid source Temperature – near maximum tolerance of E.
coli Agitation generally ranges 1000-1500 rpm Slightly positive pressure
Production Process
Purification Cell disruption Microfiltration Chromatographic methods
Genentech adapted anion exchange chromatography and gel filtration technology (early 80s)
Production Process
Issues with scale up Mass transfer through high density cells
OxygenGlucose feed
Inhibitory ion formation Acetate and formate
Final Product
White lyophilized powderLow oral bioavailability (<1%)Intended for intravenous, subcutaneous or
intramuscular administrationSold in vials or cartridges containing
4 - 24 mg of somatropin Preservatives Water for injection
Final Product
Approximately 28 day shelf lifeOxygen Sensitive Must be refrigeratedImprove the solubility, sodium dodecyl
sulfate (extremely surface active) or denaturing agents - urea and guanidine hydrochloride
Market
U.S. Manufacturers Genotropin by Pharmacia & Upjohn Company,
Humatrope by Eli Lilly, Norditropin by Novo Nordisk, Saizen and Serostim by Serono Laboratories, Nutropin by Genentech
Market
Costs: $75 to $200 per weekWorld-wide sales of $1.6 billionApproximately 20,000 U.S. children taking
drug Prescribed for non-GH-deficient children if
(U.S.) <3SD below mean for age category <25% growth velocity
Discussion
Psychological issues Cultural “heightism”
Increased metabolism, reduced fat, anti-aging, gain strength
Articles
References
Human Growth Hormone, edited by Salcatore Raiti and Robert A. Tolman, 1986
Human Growth Hormone: Research and Clinical Practice, edited by Roy G. Smith and Michael O. Thorner
Influence of Scale-Up on the Quality of Recombinant Human Growth Hormone, Bylund, Castan, Mikkola, Veide and Larsson
Modelling the effects of Glucose Feeding on a recombinant E. coli Fermentation, Cockshott and Bogle
Further Studies Related to the Scale-up of High Cell Density Escherichia coli Fed-Batch Fermentations: The Additional Effect of a Changing Microenvironment When Using Aqueous Ammonia to Control pH
References
http://pi.lilly.com/us/humatrope-pi.pdf http://www.hghnews.us/p/91.html http://www.hgh-humangrowthhormone.com/
hgh_human_growth_hormone_sitemap/hgh_manufacturer.html
http://www.novonordisk.com/therapy_areas/growth_hormone_therapy/default.asp
http://patft.uspto.gov/netacgi/ http://www.genotropin.com/patients/
growth_disorders/index.asp