Gail Naughton is president of Advanced Tissue Sciences in La Jolla, Calif., a biotechnology company that is developing skin substitutes and other human tissue products. Here is her reply.
Thanks to the relatively new field of tissue engineering, the creation of human skin, cartilage and even entire organs is either already a reality, or is becoming a realistic possibility. Tissue engineering integrates the sciences of biomaterials, cell biology, biochemistry, biomedical engineering and transplantation to create tissue and organ substitutes.
Starting with a few human cells, tissue engineers simulate the environments that allow cells to develop into viable tissue. The specific procedure varies by company, but it generally involves seeding the selected cells onto some type of matrix, where they are then are provided with, or begin to excrete, the proteins and growth factors necessary for them to grow and multiply. Following the structure of the given matrix--and given the appropriate environment--the cells eventually develop into the desired tissue.
Already, a temporary human skin substitute developed through tissue engineering is available in the U.S. for the treatment of partial or full-thickness burns (commonly known as second- or third-degree burns). Viable, metabolically active human tissue designed to help treat non-healing ulcers (such as those that frequently occur on the feet of people with diabetes and can result in amputations) is also available in some countries, and is currently being reviewed by the U.S. Food and Drug Administration. Our company is also developing small-diameter blood vessels, cartilage and even finger joints.
The primary motivation behind tissue engineering is the ongoing, dire need for available, safe and transplantable organs and tissues. Every year thousands of people die waiting for hearts, livers, lungs and kidneys simply because there aren't enough transplantable organs to go around. Similarly, the need for other human tissues such as skin and cartilage is constant, and the availability (or lack thereof) can make a real difference in the lives of burn and accident victims. Current stand-ins for these tissues--such as cadaver skin or wound dressings--are frequently less than ideal, and result in longer healing times, great expense and time, significant scarring and extensive pain for the patient.
Tissue engineering has the potential to redefine tissue and organ repair and replacement. The future holds endless possibilities. We have successfully grown not only cartilage, bone and skin but urinary tract and liver tissue. Tissue engineering will soon address the tremendous number of problems seen by patients who require replacements of skin, bone and other tissues and organs.