Patients could grow their own transplant organs or implants

Plastic surgery might soon involve transplants of skin and tissue reconstructed from bone marrow cells taken from a patient and grown artificially in the laboratory.

Scientists told the conference they have taken stem cells from a human donor and stimulated them to develop into the fatty tissue of the skin, a development that could allow patients to grow their own replacement organs for transplant surgery. Female cancer patients undergoing a mastectomy may have their breast replacements grown artificially for reconstructive surgery, said Jeremy Mao, professor of tissue engineering at the University of Illinois in Chicago.

And now key stem cells in bone marrow can be isolated, cultured in the laboratory to develop into the fatty or adipose tissue of the skin and built around a "hydrogel scaffold" to the desired shape, Professor Mao said. Hydrogel is a lightweight material already licensed for use in medicine.

The scientists implanted the hydrogel scaffolds containing the living fat cells into laboratory mice lacking immune systems, which meant they did not reject the human tissue implants. "After four weeks we found the implant was indeed generating adipose tissue from stem cells, and that its shape and dimensions were well retained," Professor Mao said.

"What we foresee for humans is that, say Jennifer Smith is unfortunate enough to have breast cancer surgery, and needs breast reconstruction; you can take adipose stem cells from her and do the same procedure. You would mould them into the shape of the other normal breast, or the missing portion of breast, and instead of implanting silicone or saline structures, we would use the stem cell-derived adipose implant."

About 6.2 million people in America alone need plastic surgery for medical reasons, 70 per cent of them because of the removal of a tumour. About as many again have plastic surgery for cosmetic reasons.

Professor Mao said growing replacement tissue from a patient's own stem cells would overcome the problems of tissue rejection that arose from tissue derived from a donor.

"The technique is also applicable for other soft tissue, facial tissue such as the lips and so on. The great thing about the stem cell-derived implant is that its shape and dimensions were retained," he said. "You could do a liposuction, harvest the stem cells, and use them for regeneration of the other structure. It could certainly be combined with other techniques.

"Patients will have a choice, a stem cell-grown structure or an artificial implant," Professor Mao added. "It will be a similar situation to other elective surgery compared to otherwise medically necessary surgery. It would be up to the patient. A lot would depend on how things were presented to the patient."

"Much of how fast this [type of treatment] will progress is a matter of regulatory issues that are hard to predict," he added. "[We believe that] the technology should be mature within a decade."