Through decellularization

Jan 14, 2008 07:50 GMT  ·  By

Broken feelings may not be repaired through engineering, but broken hearts can be. In fact, heart attack kills annually 50,000 people, only in US, and it is experienced by 550,000. A new research published in "Nature Medicine" and carried on at the University of Minnesota is the first ever to have built a beating heart tissue in the lab, through the process of decellularization, using dead rat and pig hearts.

"The idea would be to develop transplantable blood vessels or whole organs that are made from your own cells", said lead researcher Dr. Doris Taylor, director of the Center for Cardiovascular Repair, Medtronic Bakken professor of medicine and physiology.

"While there have been advances in generating heart tissue in the lab, creating an entire 3-dimensional scaffold that mimics the complex cardiac architecture and intricacies, has always been a mystery. It seems decellularization may be a solution - essentially using nature's platform to create a bioartifical heart", said Taylor.

Through decellularization all the cells from an organ (like the heart) are removed, leaving only the extracellular matrix (the inter-cell framework) untouched. Following the removal of the cells, the hearts were injected with a mix of progenitor cells from neonatal or newborn rat hearts and let to grow in a sterile setting.

"Four days after seeding the decellularized heart scaffolds with the heart cells, contractions were observed. Eight days later, the hearts were pumping. Take a section of this 'new heart' and slice it, and cells are back in there. The cells have many of the markers we associate with the heart and seem to know how to behave like heart tissue", said Taylor.

"We just took nature's own building blocks to build a new organ", said co-researcher Dr. Harald C. Ott, research associate in the center for cardiovascular repair.

"In general, the supply of donor organs is limited and once a heart is transplanted, individuals face life-long immunosuppression, often trading heart failure for high blood pressure, diabetes, and kidney failure", said Taylor. As through decellularization new donor organs are filled with the recipient's cells, this could decrease the likelihood of rejection.

"We used immature heart cells in this version, as a proof of concept. Going forward, our goal is to use a patient's stem cells to build a new heart. Although heart repair was the first goal during research, decellularization shows promising potential to change how scientists think about engineering organs. It opens a door to this notion that you can make any organ: kidney, liver, lung, pancreas", said Taylor.