Biomedical Engineering Reference
In-Depth Information
6.1 The triad of cells, scaffolds and signals come together in in situ tissue
engineering to result in tissue regeneration. In this paradigm, the cells necessary
are provided by the recipient in response to exogenous scaffolds and signals.
6.2
In situ tissue engineering
The notion-turned-reality of tissue engineering has more traditionally followed
the thought process of providing cells, scaffolds, and signals in an already
determined, often three-dimensional construct ready for implantation in, or
application on, the patient. The goal is to provide the `right' construct with the
cells still alive and able to properly interface with the host's (patient's) cells and
systems.
In situ tissue engineering is differently described as the idea that some parts
of the tissue engineering triad required for tissue regeneration can somehow be
coaxed out of the recipient's physiology to affect and complete the reparative
processes. Thus, the elegant example of salamander whole limb regeneration
after amputation is perhaps also the ultimate example of in situ tissue engineer-
ing because none of the three components of the triad must be exogenously
applied for total tissue regeneration to occur. In the absence of this ability, a
great deal of time and effort, research and development is spent trying to
determine how the non-cellular components of scaffolds and signals can be
harnessed for healing. Some fundamental questions for in situ tissue engineering
are as follows:
· What is the minimum exogenous stimulus necessary to get the healing
process rolling if stalled or alter the healing process if somehow deemed
aberrant or undesirable?
