Blood vessels from amniotic stem cells
Stem cells from amniotic fluid helped grow new vessels
In combination with the technology of tissue cultivation on a hydrogel frame, the new technique can become a real breakthrough in regenerative medicine.
An image of artificially grown vascular tissue from amniotic cells under a microscope
(Here and below are photos of Jacot Lab / Rice University).
Lead author of the study, bioengineer Jeffrey Jacot from Rice University and his colleagues published an article in the Journal of Biomedical Materials Research Part A (Benavides et al., In situ vascularization of injectable fibrin/poly(ethylene glycol) hydrogels by human amniotic fluid-derived stem cells). The scientists wrote in it that hydrogel as scaffolding in combination with amniotic stem cells allow "conducting" blood vessels to new tissues of the body and ensure normal blood flow and elimination of unnecessary waste metabolic processes.
As part of their study, Jakot and his team studied the possibility of using amniotic fluid cells of pregnant women to treat children born with congenital heart defects. According to scientists, ASCs are of great value because of their ability to differentiate into many other cell types, including endothelial cells that form blood vessels.
In the image taken using fluorescence microscopy,
blue indicates cell nuclei, red – endothelial cells,
and the green ones are smooth muscle cells.
"The main achievement of our research is that we have grown in the laboratory a tissue created entirely from cells of amniotic fluid. This means that for such experiments, only those stem cells that we get from amniotic fluid are enough," says Jakot in a press release from Rice University Amniotic stem cells demonstrate healing potential.
In their experiment, scientists have created a special type of hydrogel, which in many of its properties surpasses existing analogues. To do this, Jakot used fibrin, a special biopolymer that promotes blood clotting, wound healing and the growth of new vessels in organs and tissues. This substance is already widely used in biomedicine for the construction of skeletons, but it is characterized by low mechanical rigidity and rapid decomposition, which makes it not the best material for growing new biological structures.
"To get around this problem, we decided to add polyethylene glycol to the fibrin and as a result we got a much stronger and more durable hydrogel," says Jakot.
To accelerate the transformation of stem cells into endothelial cells, the researchers used vascular endothelial growth factor. At the same time, fibrin contributed to the penetration of natural vascular tissue from neighboring body systems.
The experiment was conducted on mice. The subjects were divided into two groups, where one – the control group – was injected with a hydrogel consisting exclusively of fibrin, and the other – a hydrogel made of fibrin and polyethylene glycol in combination with amniotic stem cells. In the former, only the growth of fibrillar structures was noticed, while representatives of the main group received a much healthier vascular network.
Jakot and his team hope that in the near future the technology developed in his laboratory will help to create biologically compatible vascular tissue implants for babies born with defects and heart defects. But before that, researchers will have to conduct many more complex experiments.
Portal "Eternal youth" http://vechnayamolodost.ru10.04.2015