Scientists have extracted a substance from bacteria that is especially suitable as a biomaterial in tissue therapy, which replaces lost tissue with something grown in a laboratory. A researcher says that the biomaterial is inexpensive, easy to produce and has all the qualities required for a biomaterial for humans.
Tissue therapy is progressing rapidly. Tissue grown in a laboratory is used to replace something the body has lost such as a piece of an organ (lost to cancer) or a section of a muscle (lost in an accident).
This future scenario envisions that the missing tissue can be replaced with something new that researchers and doctors grow outside the body and then insert.
Research has even enabled cells to be bioprinted in layers to mimic the complex layered structure tissue often has.
However, the currently available biomaterials on which the cells grow remain an obstacle in fulfilling these ambitions.
Cultivated cells need to grow on something that does not harm the body and is preferably biodegradable, so that it can be eliminated from the body.
Researchers are currently juggling expensive and complex solutions, but all these might be replaced by a potentially fantastic biomaterial researchers have extracted from Pantoea sp. bacteria, which can produce the biomaterial by the bucketload.
The research has been in published in Bioactive Materials.
“We lack inexpensive and suitable biomaterial we can use for tissue therapy to replace lost tissue. This study not only shows that bacteria can produce such a biomaterial but also that it can be used to replace muscles missing in rats,” explains a researcher behind the study, Alireza Dolatshahi-Pirouz, Group Leader and Associate Professor, Department of Health Technology, Technical University of Denmark, Kongens Lyngby, Denmark.
Bacteria can produce large quantities of biomaterials
Various biomaterials exist; some are synthetic, elastic and robust but not very cell friendly. They are also very expensive to produce.
Others, such as gelatin and other polysaccharides, are cell friendly but not very robust and break down quickly – also inside the body.
Researchers in this field would ideally like to find a cell-friendly material with the same properties as the synthetic versions but simpler and less expensive to produce.
The bioactive polysaccharide derived from the extracellular matrix of Pantoea sp. fits the bill. Alireza Dolatshahi-Pirouz and colleagues discovered this and call it pantoan methacrylate (PAMA).
PAMA is a photo-crosslinkable hydrogel that is elastic, resilient and cell friendly. PAMA is also inexpensive to produce, because bacteria can produce it in large tanks.
“Our experiments have shown that PAMA can readily be printed into complex shapes, that cells can grow on PAMA and differentiate into muscle cells and that PAMA is very elastic. These properties are all together very good for muscle tissue engineering, since muscles are very active. This furthermore gives PAMA great potential for bioprinting of cells and for muscle tissue engineering,” says Alireza Dolatshahi-Pirouz.
Replaced muscles in rats
The researchers further confirmed that PAMA can replace lost tissue in rats that had a piece of thigh muscle removed.
The researchers inserted PAMA into the cavity in the rats’ thighs and enabled it to form new muscle tissue there. PAMA turned out to be very suitable for this.
The rats with the artificial muscle implant formed twice as many muscle fibres as rats not treated with artificial tissue. The treated rats also formed only half as much scar tissue.
Various studies on inflammation and other topics also showed that the body tolerated the implanted PAMA well.
“This indicates that PAMA may be a suitable alternative to synthetically producing biofriendly materials for growing cells for tissue therapy. We have shown that this can have potential in muscle repair, but it might be used in other types of tissue therapy replacing lost tissue with an artificial biomaterial,” concludes Alireza Dolatshahi-Pirouz.
