New generation of biological scaffolds for tissue transplants
15 July 2010
A new technique for making biological scaffolds developed at
the University of Leeds will pave the way for off- the-shelf tissue
Professor John Fisher and colleague Professor Eileen Ingham have
been working on ways of producing biological scaffolds, derived from
natural human or animal tissues such as vascular patches, meniscus
(knee cartilage), and tendons that will not be rejected by a
patient's immune system and can be repaired and renewed like normal
The research was presented yesterday at the UK National Stem Cell
Network Annual Science Meeting in Nottingham.
The technique developed by the Leeds group removes the cells from
natural tissues to leave a biological scaffold which can be
regenerated by the patient's own cells. Scaffolds derived from human
donor tissue are being developed by the NHS Blood & Transplant
Tissue Services, while scaffolds developed from animal tissues are
being developed and commercialised by Tissue Regenix Group PLC.
Professor Fisher said: "If you take a natural tissue and strip
off all of the donor's cells you're left with a biological scaffold
made mostly of a protein called collagen, which is compatible with
the patient receiving the scaffold.
That scaffold is good from an engineering perspective because
it's strong, flexible and retains the properties of the natural
tissue. It also has the appropriate shape and size, and from a
biological perspective is good because a patient's cells can bind to
it and repopulate it easily."
Because a patient's own cells can populate the new biological
scaffolds, they are accepted by the immune system and can be
repaired like normal tissue. There is a significant advantage from
this technique because of the longevity of the transplant compared
to other previously developed techniques.
Chemically treated and strengthened prosthetic heart valves from
pigs, for example, have been in used in human transplants for more
than a decade, but the chemical process which stops them from being
rejected by the patient's immune system also leaves them lifeless
and inert. Because they cannot be repaired like living tissues,
these prosthetic valves are degraded over time and need to be
Professor Fisher continued: "These new biological scaffolds will
provide off-the-shelf tissues for surgeons for repairing blood
vessels after surgery for blocked arteries, for repairing meniscus
after sporting injuries and cartilage tears, for repairing torn
ligaments or tendons and for heart valve repair or replacement."
This research is being developed in conjunction with the NHS
Blood & Transplant Tissue Services and with Tissue Regenix Group
PLC, a company set up by researchers to bring new biological
scaffolds to market. Funding for the research in this area also came
via the Engineering and Physical Sciences Research Council (EPSRC),
the Biotechnology and Biological Sciences Research Council (BBSRC),
the Children's Heart Surgery Fund, the Department of Health and the