Instead of moving skin from other parts of the body or operating in prostheses of non-biological material, it is becoming more and more common for plastic surgeons to cultivate the patient’s own cells to make repairs. In burn injuries, for example, derma cells are cultivated from epithelium cells and then grow onto the surface of the wound.
But to go deeper, other methods are called for. The research team at Linköping University has studied various ways to cultivate the cell type needed in a matrix, a “scaffolding,” and then to apply it to the body. The best results were attained using porous spheres of micro format (a few hundredths of a millimeter in diameter) consisting of gelatin-a substance that occurs naturally in the human body.
“These spheres offer multiple advantages. Enormous numbers of cells can be cultivated in the gelatin, and the material can also be injected in the patient,” says Fredrik Huss, a plastic surgeon in training who describes the method in his doctoral dissertation to be defended on September 2.
All types of cells attempted grew extremely well in the gelatin balls: skin cells, connecting tissue cells, cartilage cells, early stages of fat cells, and mammary gland cells. Experiments with transplanting in mice also yielded favorable results. Injection under the skin of spheres containing connecting tissue cells and fat cells led to good regeneration of tissue. But it is not even necessary to cultivate the cells in advance. Empty balls were injected into the upper arm of healthy volunteers. For comparison, saline solution and Resylane®, a commonly used anti-wrinkle substance, were injected. The result was excellent regeneration of tissue inside the spheres, which were then degraded and disappeared, and there were no signs of rejection. On the other hand, Restylane® injection produced no new generation of tissue.
“Our findings open up tremendous potential for the repair of soft body parts. It is a simpler and more dependable method than the fat transplants carried out today,” says Fredrik Huss, who, together with Elof Eriksson, is participating in an international research conference on tissue engineering TERM 2005, arranged by Linköping University. For the program, see http://www.liu.se/forskning/filer/program-term2.pdf.