Converting skin cells to stem cells creates ‘kidney structures’

first_imgHarvard Stem Cell Institute (HSCI) principal faculty at Brigham and Women’s Hospital (BWH) have established a highly efficient method for making kidney structures from stem cells derived from skin taken from patients. The kidney structures formed could be used to study abnormalities of kidney development, chronic kidney disease, and the effects of toxic drugs, and could be incorporated into bioengineered devices to treat patients with acute and chronic kidney injury. In the longer term, these methods could hasten progress toward replacing a damaged or diseased kidney with tissue derived from a patient’s own cells.The work was published in Nature Biotechnology.“Kidneys are the most commonly transplanted organs, but demand far outweighs supply,” said co-corresponding author Ryuji Morizane, associate biologist in BWH’s Renal Division. Morizane worked in collaboration with HSCI researchers Joseph Bonventre, Albert Lam, and M. Todd Valerius.“We have converted skin cells to stem cells and developed a highly efficient process to convert these stem cells into kidney structures that resemble those found in a normal human kidney,” Morizane said. “We’re hopeful that this finding will pave the way for the future creation of kidney tissues that could function in a patient and eliminate the need for transplantation from a donor.”Chronic kidney disease (CKD) affects 9 to11 percent of the U.S. adult population and is a serious public health problem worldwide. Central to the progression of CKD is the gradual and irreversible loss of nephrons, the individual functional units of the kidney. Patients with end-stage kidney disease benefit from treatments such as dialysis and kidney transplantation, but these approaches have several limitations, including the limited supply of compatible organ donors.While the human kidney does have some capacity to repair itself after injury, it is not able to regenerate new nephrons. In previous studies, researchers have successfully differentiated stem cells into heart, liver, pancreas, or nerve cells by adding certain chemicals, but kidney cells have proven challenging. Using normal kidney development as a roadmap, the investigators developed an efficient method of creating kidney precursor cells that self-assemble into structures that mimic complex structures of the kidney. The research team further tested these organoids — three-dimensional organ structures grown in the lab — and found that they could be used to model kidney development and susceptibility of the kidney tissue to therapeutic drug toxicity. The kidney structures also have the potential to facilitate further studies of how abnormalities occur as the human kidney develops in the uterus and to establish models of disease in which they can be used to test new therapies.“This new finding could hasten progress to model human disease, find new therapeutic agents, identify patient-specific susceptibility to toxicity of drugs, and may one day result in replacement of human kidney tissue in patients with kidney disease from cells derived from that same patient,” said Bonventre, an HSCI principal faculty member. “This approach is especially attractive because the tissues obtained would be ‘personalized’ and, because of their genetic identity to the patient from whom they were derived, this approach may ultimately lead to tissue replacement without the need for suppression of the immune system.”last_img read more


Cohen: In return to field, Sales proves he can be counted on to be consistent weapon for 2012 season

first_img Related Stories ONE TOO MANY: Costly mistakes by Syracuse waste comeback bid in 42-41 lossDominant performance by Nassib still not enough for Syracuse to pull out victoryNorthwestern running back Mark powers rushing attack; Smith, Gulley give Syracuse strong performances out of backfieldCohen: In return to field, Sales proves he can be counted on to be consistent weapon for 2012 seasonSyracuse loses to Northwestern 42-41 There was a sort of mysticism swirling around Marcus Sales, the player whose football career seemed more mythical than anything else.He was the local boy, the former high school All-American and four-star recruit who stayed at home to play for Syracuse, and whose commitment was the crowning jewel for a struggling program.It meant his story was written early, his tale of triumph penned before the ink used to sign his scholarship even dried.But no one foresees the bumps in the road that cause the fairytale to veer off into uncertainty, disaster even. In Sales’ case, those bumps were work ethic problems, poor on-field performances, and an arrest and subsequent suspension that took away his 2011 season.Saturday against Northwestern was Sales’ shot at redemption, and he seized it. The storm was weathered, the suspension served and Sales turned in an outstanding 11-catch, 117-yard, one-touchdown performance in his first football game in more than a year.AdvertisementThis is placeholder textHe cast aside doubts on whether his legendary Pinstripe Bowl performance was a fluke and firmly cemented himself as one of Syracuse’s most dangerous weapons for the 2012 season, even though the Orange eventually fell to the Wildcats 42-41.“I have trusted Marcus since we came here together,” quarterback Ryan Nassib said. “He made my job a lot easier. … I was really happy with how we connected today.”On what was a record-setting day for Nassib, who threw for 470 yards and four touchdowns, Sales was undoubtedly his favorite target. Twenty-five percent of his completions were hauled in by Sales, including the seven-yard touchdown late in the third quarter that ignited the Syracuse comeback.Most impressive, though, was how sharp Sales looked in other aspects of the game beyond simply catching the football, in which his natural abilities could often overshadow rust following his year off.His beautiful block on Northwestern cornerback Nick VanHoose in the second quarter sealed the edge for Jerome Smith on a toss play to the outside that gained six yards. Then, on the very next snap, he caught a play-action pass from Nassib and cut to the outside with a move that caused linebacker Chi Chi Ariguzo’s knee to buckle, forcing him to walk gingerly off the field.“Marcus looked like he had been here before, he wasn’t nervous,” Syracuse defensive end Brandon Sharpe said. “He was ready for the game and came out fired up.”It took until his junior year for Sales to truly burst onto the scene the way SU fans and coaches expected he would after a standout career at Christian Brothers Academy. And, even then, it was only in the final game of the season in which Sales 2.0 was born.Running back Delone Carter took home Pinstripe Bowl Most Valuable Player honors, but it could certainly be argued that Sales stole the show. He caught five passes for 172 yards and three touchdowns in Syracuse’s 36-34 win over Kansas State after hauling in only four touchdowns in the previous two years combined.Nathaniel Hackett, who was the quarterbacks coach at the time and is currently SU’s offensive coordinator, said Sales had finally bought into the system in the month leading up to the Pinstripe Bowl. His practice habits improved, he was putting in the effort and everyone saw the results.So when Sales posted another impressive performance on Saturday — he’s caught 16 passes for 289 yards and four touchdowns over his last two games — it confirmed his new identity and erased the memories of the player whose first catch of the 2010 season didn’t come until week five.Shockingly, both Hackett and Marrone said their budding star is capable of even more production.“I think that Marcus can do a better job. I really do,” Marrone said. “He’s come back; I think he got himself off to a good start. But, each week, we have to get better each day and raise our level.”It’s a fantastic sign considering Syracuse played on Saturday without its most consistent wide receiver in senior Alec Lemon. That means Sales was still able to haul in 10-plus passes, despite the fact that he was the focal point of the Northwestern secondary.Sales said himself that he can’t be satisfied with 11 catches — four more than his previous career high — since Syracuse still wound up on the wrong end of the scoreboard.“Maybe I need to get 13 next time to get the victory,” he quipped.And it certainly seems possible with his recommitment to the game and the suddenly pass-happy SU offense.That he could miss a year but not miss a beat is a testament to his talent, a reflection of the above-average work ethic that once eluded him.It only took one game to show that Sales 2.0 is here to stay, and Syracuse is much better off for it.Myth debunked.Michael Cohen is a staff writer for The Daily Orange, where his column appears occasionally. He can be reached at [email protected] or on Twitter at @Michael_Cohen13. Comments Published on September 2, 2012 at 4:28 pmcenter_img Facebook Twitter Google+last_img read more