transplants

Japanese scientists have developed tiny liver organoids from stem cells that, transplanted into mice, integrate with the original organ and help repair fibrotic lesions. This scar-like tissue damage is common to many liver diseases, such as fatty liver disease and cirrhosis. According to the authors, who publish their results in the journal Science Translational Medicine, such organoids could offer an alternative to liver transplants in the future.

Currently, when an organ transplant is performed, the patient has to take immunosuppressive drugs to prevent his or her system from rejecting the new organ. These drugs must be taken for life and have numerous side effects. In a phase 1 clinical trial, researchers gave patients receiving a liver transplant regulatory dendritic cells derived from the original donor, with the hypothesis that these cells could 'teach' the recipient's immune system to tolerate the new organ. The research, published in Science Translational Medicine, suggests that this treatment could reduce or even eliminate the need for long-term use of immunosuppressants.

Scientists have successfully developed pig embryos whose kidneys contain 50-60% human cells. Gestation was terminated at 25-28 days, and the organ structure was normal. According to the press release accompanying the article, "this is the first time that a solid humanised organ has been grown inside another species, although previous studies have used similar methods to generate human tissues". The results are published in the journal Cell Stem Cell. 

A clinical team in the US has successfully transferred kidneys from pigs to a brain-dead man. The organs came from animals that had been genetically modified to prevent rejection by the immune system of the patient, who had kidney disease. The transplanted organs were functional - they could make urine and clear creatinine - seven days after the operation, explains a research letter summarising the case in JAMA Surgery. The team says this type of xenotransplantation - from animal to human - could be a solution to the shortage of donor organs. 

Researchers have developed a system capable of restoring some molecular and cellular functions and preserving tissues in pigs when initiated one hour after death. The study is published today in the journal Nature.