Melbourne: It may soon be possible for men with type 1 diabetes to use stem cells from their testicles to replace their damaged insulin-secreting beta islet cells, say US scientists.
The new research details how the cells, which would normally become sperm, can be coaxed into taking on this new role.
Lead author Associate Professor Ian Gallicano from Georgetown University in Washington DC, says that this is a proof-of-principle study for which they obtained the "spermatagonial" stem cells (SSCs) from the testes of deceased human organ donors.
"From one gram of tissue we were able to obtain more than a million beta islet-like cells that were successfully used to treat diabetic mice," ABC Science quoted him as saying.
It``s a two-step process. First the SSCs are ``de-differentiated`` to become embryonic-like stem cells, meaning they have the potential to form any cell type in the body. This takes two weeks. Then, over the course of the next three weeks, these cells are given specific nutrients to ensure they grow into beta islet-like cells.
While Gallicano`s team were able to decrease blood sugar levels in three mice for up to a week, he explains this is not their most important finding.
"Transplanted beta islet-like cells don`t need to be producing much insulin to ``cure`` a mouse with diabetes - this has been done before, using beta islet-like cells derived from other types of adult stem cells; but these have been reprogrammed using genetic manipulation, which has potential problems. We didn`t need to do any genetic manipulation to get the SSCs to become embryonic-like stem cells," he says.
"One reason that the mouse work hasn`t translated into human benefit is that there are currently no [laboratory-derived] cells that secrete enough insulin to be clinically relevant.
"The target is to have 1-10 percent of protein from a cell as insulin. The best cells I`ve seen are secreting between 0.01 and 0.1 percent, so a 10-100 times increase is needed," he says.
The study has been presented at the 50th annual meeting of the American Society of Cell Biology in Philadelphia.