Blood vessel transplant success

Technion Scientists have succeeded for the First Time in Transplanting Engineered Tissue Bearing Major Blood Vessel to Repair Severe Abdominal Muscle Injury

Till now scientists have only successfully transplanted engineered muscle tissue bearing small blood vessels

Technion scientists succeeded for the first time to transplant engineered tissue bearing major blood vessels to repair severe abdominal muscle injury, as published by the prestigious US science journal ‘Proceedings of the National Academy of Sciences’ (PNAS). In the past, researchers were only successful in transplanting engineered muscle tissue with small blood vessels. This medical breakthrough may do away with the need for complex surgeries in the future, and the Technion holds a patent on it.

Professor Shulamit Levenberg from the Technion’s Faculty of Biomedical Engineering and the Russell Berrie Nanotechnology Institute explains that in the current study, researchers fabricated an engineered muscle flap bearing its own functional vascular pedicle for repair of a large soft tissue defect. Technion scientists successfully reconstructed a full-thickness abdominal wall defect using this engineered vascular muscle flap in a mouse.

In tissue reconstruction, two approaches exist to address the clinical challenges involved in the successful restoration of tissue defects: 1) GRAFT where tissue is being transplanted  to the damaged area. The blood vessels in the body penetrate the tissue and nourish it with a blood supply.

2) FLAP – where tissue is being transplanted to the damaged region with its own blood supply. Flaps are used for treating injured areas where there is an absence of blood supply and when postimplantational vascularization is not established, such as in cases of soft tissue defect closure, or exposed bone, cartilage or tendons.

Tissue engineering constructs laboratory-grown tissue for transplantation. In this study, the engineered tissue was a three dimensional engineered tissue constructed of a porous, biodegradable polymer scaffold embedded with endothelial cells, supporting stromal cells (fibroblasts), and muscle cells (myoblasts). The tissue was grown in the lab by Technion researchers and then implanted to the region around the (femoral) artery and veins in the thigh, before being transferred as a flap. The flap is the stage where tissues can be transferred with their own blood supply and are joined to the blood vessels in the region of transplant, to repair large defects, such as in the abdominal wall region.

Grafts are effective for repairing small defects, but ineffective at repairing severe injury. Consequently, this medical breakthrough is very noteworthy.

The study was performed in collaboration with Dr. Yulia Shandalov (who was a doctoral student of Professor Levenberg during the time of the study), and Dr. Dana Egozi, from the Department of Plastic and Reconstructive Surgery at the Rambam Health Care Campus, who was recently appointed Director of the Department of Plastic Surgery  at the of Kaplan Medical Center.

The study is part of a research project led by Professor Shulamit Levenberg, funded by the European Research Council (ERC) in the amount of 1.5 million euros.