Do you know of anyone who has died from organ failure? Do you have a family member who is at risk of heart disease? Is there anyone around you suffering from liver or kidney failure? It would not be surprising if you do. Organ failure is one of the top ten leading causes of death in the United States (National Center for Health Statistics [NCHS], 1997). Every year, around 100,000 people in the U.S. need an organ transplant; sadly, only 25% of them will ever get one (Ball, 2000). As a result, 20,000 Americans die every year as they wait for an organ (Abdullah, 1999). In a recent transplantation tragedy, 17-year-old Jesica Santillan died after receiving heart and lungs from a donor of a different blood type in a botched operation performed at Duke Hospital (Kirkpatrick, 2003). Such tragedies could be avoided if the transplanted organs were instead fabricated from the patient’s cells.

As organ failure claims more and more lives, it is imperative that we find a solution to the lack of donated organs. One obvious solution is to increase the efforts of organ donation campaigns. An alternative solution is organ fabrication. Organ fabrication involves the growth of living cells into entire organs, in an environment outside the human body. However, before fabricated organs can become a standard treatment for organ failure, scientists have to determine how to create an effective scaffold upon which cells can develop into organs. Dr. Chen Guoping and his team at the National Institute of Advanced Interdisciplinary Research (NAIR) have successfully developed a method for the creation of such a scaffold (Chen et al, 2000), which will accelerate the development of organ fabrication.

The scaffold that Dr Chen and his team developed surpasses scaffolds currently used in tissue fabrication (the process by which living cells grow into tissues in an environment outside the human body). Conventional scaffolds used in tissue fabrication fail certain essential criteria that render them ineffective for organ fabrication (Chen et al, 2000). Conventional scaffolds are made of either synthetic polymers or collagen (collagen is the connective tissue found in tendon and cartilage), and these materials have inherent problems that lead to a lower quality of cell growth necessary for organ fabrication. Synthetic polymers are hydrophobic (water-repelling) so that cells, which are composed of 70% water, do not adhere successfully to the synthetic scaffolds (Chen et al, 2000). This is a major obstacle in organ engineering where high rates of cell growth and cell coverage are essential. On the other hand, collagen scaffolds are difficult to process into different shapes and limits the kinds of organs that can be grown (Chen et al, 2000). Collagen also lacks mechanical strength (Chen et al, 2003) and cannot be used in the scaffolding for the growth of bones (Lee, 2001).

Dr Chen and his team at the NAIR combined both synthetic polymers and collagen to create the new hybrid scaffold (Chen et al, 2000). They carried out tests that showed this scaffold to be a better template for the growth of cells and consequently more effective for the growth of organs. Cells were implanted onto both the new hybrid scaffold and the conventional synthetic one (Chen et al, 2000). Twice as many cells adhered to the new scaffold than on the conventional one, and the cells on the new hybrid scaffold developed more uniformly and extensively (Chen et al, 2000). Such high rates of cell adherence and uniform coverage facilitates the growth of organs. This new scaffold also has pore sizes that can be varied and a higher mechanical strength than conventional scaffolds (Chen et al, 2000). In addition, the new hybrid scaffold is easier to manipulate into different shapes than the collagen scaffold. These features contribute to the versatility of the scaffold for the growth of different cells, which will be especially useful when harnessing cells to make an organ.

The creation of this new hybrid scaffold has helped tissue engineers overcome one major obstacle in fabricating organs. Admittedly, the development of the effective hybrid scaffold does not guarantee success in organ fabrication. More research has to be done to surmount other problems in order for it to become a reality. But tissue engineers are at least one step closer to engineering organs and one step closer to saving the 80,530 patients on the organ waiting list who might otherwise die (OPTN, 2003).

Sources:

Ball, P. Nature Science Updates. (2000, March 13). Seeds of Hope. Retrieved January 24, 2003, from http://www.nature.com/nsu/000316/000316-4.html

Adulla, S. Nature Science Updates. (1999, October 11). Printing a Heart. Retrieved January 24, 2003, from
http://www.nature.com/nsu/991014/991014-5.html

Kirkpatrick C.D. The Herald Sun (2003, February 18). Teen Transplant Victim at Duke Fights for Life. Retrieved February 18, 2003, from
http://heraldsun.com/durham/4-321877.html

National Center for Health Statistics (1997). Number of Adults with Kidney Disease, by Sex, Race, Age, and Geographic Region. Retrieved February 1, 2003, from
http://www.cdc.gov/nchs/fastats/pdf/sr10_205t7.pdf

The Organ Procurement and Transplantation Network (2003) Critical Data. Retrieved February 17,2003, from http://www.optn.org

Lee,G. (2001). Creating and Growing Body Parts. Innovation. Retrieved January 24, 2003, from http://www.innovationmagazine.com/innovation/vol02_03/vol02_03.shtml

Chen, G. Ushida, T. Tateishi, T (2000) Hybrid Biomaterials for Tissue Engineering: A Preparative Method for PLA or PLGA-Collagen Hybrid Sponges [Electronic Version] Advanced Materials, 12, 455-457.
-Stable URL link: http://dx.doi.org/ 10.1002/(SICI)1521-4095(200003)12:6<455::AID-ADMA455>3.0.CO;2-C

Chen, G. Ushida, T. Tateishi, T (2000) A biodegradable hybrid sponge nested with collagen microsponges [Electronic Version] Journal of Biomedical Materials Research, 51, 273-279.
-Stable URL link: http://dx.doi.org/ 10.1002/(SICI)1097-4636(200008)51:2<273::AID-JBM16>3.0.CO;2-O