Artificial Tissue and Organ Generation

Valerie FortinBME 281

Organ Transplants Autografts

Transplanted within a patient Surplus, nonvital, or regenerating tissue e.g. skin grafts

Allografts Transplanted from a separate living or

deceased donor Isographs

Transplant from genetically identical individual e.g. twins

Types of Donations

Organs Heart Liver Kidneys Lungs Pancreas Intestines

Tissues Cornea Skin Heart Valves Tendons

Problems

Availability In 2012, 28,051 people received organs On average, 79 people receive organs daily,

but 18 people die due to shortage Rejection

In allografts, donor tissue differs genetically Triggers an immune response

Ethical Concerns

Organ donation has caused some controversy WHO has released guiding principles

May only harvest from deceased persons with legal permission OR “ there is no reason to believe that the deceased person objected to such removal”

Opt Out system

“In general living donors should be genetically, legally or emotionally related to their recipients.“

Donors cannot be monetarily compensated Concerns of trafficking and profiteering

Organs or tissues which were obtained through coercion or exploitation should not be used

Regenerative Medicine

Uses a patient's own cells to restore Includes use of stem cells Can grow tissues and organs on sterile

scaffold

Scaffolds

Artificial structure Cells are “seeded” onto it Which then grow to form the desired tissue

Materials Biodegradable preferred Collagen, polyesters Polylactic acid

Degrades into lactic acid Polyglycolic and polycaprolactone for differing

degradation speeds

Scaffolds (cont.)

Can also decellularize extracted tissue samples

Sterilized cellular matrices act as scaffold

Vascular graft

Scaffolds (cont.)

Rat heart grown around a decellularized scaffold

Benefits

All genetic material supplied by patient Eliminates potential for rejection Bypasses need for donor

No wait list No compatibility issues No moral qualms

Drawbacks

Currently limited Can only produce simple hollow structures

Few cell layers Stomach, bladder, blood vessels Solid organs are more complex

New procedure Doubts that grown organs are as durable or

effective as donated ones Will be expensive

Future

Practice will become more widespread, commonplace

Be able to better assess quality of grown organs

Develop means of synthesizing more complex structures

Citation Heike Mertsching, Thorsten Walles, Michael Hofmann, Johanna Schanz, Wolfram H. Knapp, Engineering of a

vascularized scaffold for artificial tissue and organ generation, Biomaterials, Volume 26, Issue 33, November 2005, Pages 6610-6617, ISSN 0142-9612, http://dx.doi.org/10.1016/j.biomaterials.2005.04.048. <http://www.sciencedirect.com/science/article/pii/S0142961205003169>

"All About Donation." What Organs Can Be Donated. New York Organ Donor Network, n.d. Web. 27 Oct. 2013. <http://www.donatelifeny.org/about-donation/what-can-be-donated/>.

"Human Cell and Tissue Transplantation." WHO. World Health Organization, n.d. Web. 27 Oct. 2013. <http://www.who.int/transplantation/cell_tissue/en/>.

“Human organ and tissue transplantation.” World Health Organization 26 Mar. 2009. <http://apps.who.int/gb/ebwha/pdf_files/A62/A62_15-en.pdf>

Neck, Haddam. "Doctors Grow Organs from Patients' Own Cells." CNN. Cable News Network, n.d. Web. 24 Oct. 2013. <http://edition.cnn.com/2006/HEALTH/conditions/04/03/engineered.organs/index.html>.

"The Need Is Real: Data." Organdonor.gov. Division of Transplantation, n.d. Web. 24 Oct. 2013. <http://www.organdonor.gov/about/data.html>.

NOONAN, DR. JESSICA. "Lab-Grown 'Custom' Organs May Be Future of Medicine." ABC News. ABC News Network, n.d. Web. 27 Oct. 2013. <http://abcnews.go.com/Health/lab-grown-custom-organs-future-medicine/story?id=16631764>.