Insulin-producing mini stomachs promise patient-specific diabetes treatment
Patients with Type 1 diabetes suffer from an absence of pancreatic cells called beta cells, which are responsible for producing insulin. Researchers have been trying to tackle the deficiency for decades, but now it seems that significant progress may have been made – a team of scientists lead by researchers from the Harvard Stem Cell Institute have discovered that it might be possible to engineer tissue from the lower stomach to address patients' insulin needs.
For the new study, the researchersworked with laboratory mice genetically engineered to express threegenes that can, under the right circumstances, turn other cell typesinto beta cells. The team carefully studied the mice, testing eachpart of their anatomy for the most amenable cells for conversion.After much analysis, it was determined that cells from the pylorus region, which connects the stomach to the small intestine, were thebest candidates.
The cells were found to be mostresponsive to high levels of glucose, normalizing the subject's bloodsugar by producing insulin. Their effectiveness was tested when theresearchers intentionally destroyed the creature's pancreatic betacells, effectively forcing the cells to respond if the subject was tosurvive.
The results of the test were verypositive, with the mice surviving for the entire length of the study– some six months – with their reprogrammed pyloric cellsproducing insulin to keep blood sugar levels in check. By contrast,control animals without the reprogrammed tissue died within eightweeks.
Looking towards converting their findingsinto a usable treatment, the researchers took a slightly different approach.As turning on the three genes responsible for the insulin productionisn't a good option for human trials, the team instead extractedstomach tissue from the mice and engineered it in a lab environment,growing the cells into miniature stomachs capable of producinginsulin and replenishing themselves.
These mini-organs were tested in thelaboratory mice, with the researchers implanting them in the membranecovering the inside of the animals' abdominal cavity. The team then destroyed the mice's ability to produce insulin, finding thatthe mini-organs compensated at the expected success rate, with theglucose levels of five out of 22 test animals staying normal.
The team plans to continue its work,and hopes to develop the research into an effective clinical therapy that's tailored to individual patients.
"What is potentially really great aboutthis approach is that one can biopsy from an individual person, growthe cells in vitro and reprogram them to beta cells, and thentransplant them to create a patient-specific therapy," said seniorpaper author Qiao Zhou. "That's what we're working on now. We're veryexcited."
The research was published in thejournal Cell Stem Cell.
Source: Cell Press via Eureka Alert