Until now, according to Colin Fernandez, a science writer for the UK Daily Mail, scientists have been limited to growing only small pieces of human tissue in the laboratory. Growing large pieces did not succeed because the oxygen supply failed to get to the cells in the center leaving a hole in the middle of the structure.
Researchers at the universities of Bristol and Liverpool have used cartilage tissue engineering as a way of testing a new method of overcoming the oxygen problem. They created a new artificial membrane binding protein, called myoglobin, which they attached to stem cells before they use them to repair cartilage. Each cell thus has its own oxygen reservoir that it can access when oxygen in the scaffold drops to dangerously low levels. Attaching myoglobin, which is commonly found in muscles, meant the stem cells were fully oxygenated during the early stages of the growing process.
Fernandez quoted Adam Perriman, Ph.D., from Bristol’s School of Cellular and Molecular Medicine, as saying, “From our preliminary experiments, we found that we could produce these artificial membrane binding proteins and paint the cells without affecting their biological function. We were surprised and delighted to discover that we could deliver the necessary quantity to the cells to supplement their oxygen requirements. It’s like supplying each cell with its own scuba tank, which it can use to breathe from when there is not enough oxygen in the local environment.”
Called a “breakthrough” by the Daily Mail, the development solved the problem of the hole and should pave the way for the development of a wide range of new biotechnologies.
Professor Anthony Hollander, Ph.D., of the University of Liverpool, said, “We have already shown that stem cells can help create parts of the body that can be successfully transplanted into patients, but we have now found a way of making their success even better. Growing large organs remains a huge challenge but with this technology we have overcome one of the major hurdles.”
“Creating larger pieces of cartilage gives us a possible way of repairing some of the worst damage to human joint tissue, such as the debilitating changes seen in hip or knee osteoarthritis or the severe injuries caused by major trauma….” A description of the process is published in the journal Nature Communications.
