Over 20 million people in Europe suffer from
osteoarthritis(骨关节炎) which can lead to extensive damage to the knee and
hip1 cartilage(软骨). Stem cells offer a
promising2 way forward but a key challenge has been to design a 'smart material' that is biologically effective for cartilage tissue regeneration. Now researchers have identified a blend of naturally occurring fibres such as cellulose and silk that makes progress towards
affordable3 and effective cell-based therapy for cartilage repair a step closer. The EPSRC-funded study, published in Biomacromolecules and undertaken by University of Bristol researchers, explored the feasibility of using natural fibres such as silk and cellulose as stem cell scaffolds -- the matrix to which stem cells can cling to as they grow.
Both cellulose and silk are commonly used in textiles but the researchers demonstrated an unexpected use for the two natural polymers when mixed with stem cells. The team treated blends of silk and cellulose for use as a tiny scaffold that allows adult connective tissue stem cells to form into preliminary form of
chondrocytes(软骨细胞) -- the cells that make healthy tissue cartilage -- and
secrete4 extracellular matrix similar to natural cartilage.
Dr Wael Kafienah, lead author from the University's School of
Cellular5 and
Molecular6 Medicine, said: "We were surprised with this finding, the blend seems to provide complex chemical and mechanical cues that induce stem cell
differentiation7 into preliminary form of chondrocytes without need for biochemical
induction8 using expensive
soluble9 differentiation factors. This new blend can cut the cost for health providers and makes progress towards effective cell-based therapy for cartilage repair a step closer."
Dr Sameer Rahatekar, lead author from the University's Advanced Composite Centre for Innovation and Science (ACCIS), added: "We used ionic liquids for the first time to produce cellulose and silk scaffolds for stem cells differentiation. These liquids are effective in dissolving biopolymers and are environmentally
benign10 compared to traditional
solvents11 used for processing of cellulose and silk."
The teams are currently working on the fabrication of 3D structures from the blend suitable for implantation in patient
joints12 with future studies focusing on understanding the
peculiar13 interactions between the blend and stem cells towards refining the quality of
regenerated14 cartilage.