Working on Bone Tissue Engineering
In the field of tissue engineering at present the work on simpler tissues and smaller tissue sections is the closest to widespread commercial realization. Most of the leading lines of research and development involve the use of decellularization, in which donor tissue, which can be from a different species, is stripped of its cells leaving behind the intricate structure of the extracellular matrix. That acts as a scaffold to guide repopulation with cells grown from a patient sample, producing functional tissue ready for transplantation. Here is a short interview with a tissue engineer working on the generation of bone sections:
At the moment, the only way to get bone for grafts is to cut it out of a human. If you need a piece of bone for, say, your ankle, they'll cut it out of your hip. There are several million of these bone-grafting procedures done every year worldwide. The idea is to grow bone from a patient's own cells so they won't need that second surgery and so the implanted bone won't be immunologically rejected. First, we'll take a CT scan to get the 3D structure of a patient's bone and use a high-precision machine to carve a decellularised bovine bone into the required shape. Then we'll take fat tissue from a patient and extract stem cells from it. We combine the stem cells with the piece of carved bone and put it into a bioreactor. That's where the magic happens - after three weeks in the bioreactor we have a piece of bone ready for implantation.We're working in pigs at the moment but will use the same principle for humans. Pigs are a good fit for the bone we're working on. We wanted a strong proof of concept so chose the most difficult bone in the head - the temporomandibular joint for the jaw. Pigs are great because they've got a very similar sized head to humans and use the bone in a similar way, in a kind of circular chewing motion. The science is getting really close. We're about to start a second, larger study in pigs and are doing work in preparation for human clinical trials with the FDA. We are also planning small-scale implantations in humans in the next year and a half. So pretty soon hopefully!
Link: http://www.theguardian.com/technology/2014/dec/07/bones-grown-lab-biotech-grafts