A research team from the UCL Tissue Repair and Engineering Centre (TREC), the UCL Eastman Dental Institute and the UCL Institute of Orthopaedics, has pioneered a novel technique for engineering tissues, which has the capacity to greatly reduce the time taken to fabricate implantable human tissue.
Tissue engineering is a method whereby the patient has cells extracted from his or her body and grown under laboratory conditions for a myriad of applications such as cartilage, skin grafts, heart valves and tendons, without the risk of rejection, infection or the ethical dilemma involved in transplanting a donated organ.
Current tissue engineering methods depend on the ability of the cultured cells themselves to grow new tissue around a cell scaffold, which is slow, expensive and has limited success. Professor Brown’s process is cell-independent, the controlled engineering of scaffolds is achieved by rapidly removing fluid from hyper-hydrated collagen gels.
The fluid is removed by employing plastic compression, a process that the team found produces dense, cellular, mechanically strong collagen structures that can be controlled at nano and micro scales and which mimic biochemical processes.
Scanning electron micrograph of spiralled plastic compression constructs.
Macro picture of a ‘ligament’ construct with ‘boney’ end at the top (with hydroxyapatite) and collagen (pink) rod below.
Principal investigator Professor Robert Brown (UCL TREC) said: “The fluid removal dramatically shrinks the collagen by well over 100 times its original volume, which provides the ability to introduce controlled mechanical properties, and tissue-like microlayering, without cell participation. Crucially, this takes minutes instead of the conventional days and weeks without substantial harm to the embedded cells. The rapidity and biomimetic potential of the plastic compression fabrication process opens a new route for the production of biomaterials and patient-customised tissues and represents a new concept in ‘engineered’ tissues.”
A paper describing the process in detail will be published in the October edition of the ‘Advanced Functional Materials’ journal.