by • February 10, 2016 • No Comments
From expanding a full thymus gland within a mouse, to creating a slice of artificial liver tissue, to via ink jet printing innovation to turn it into a human ear, researchers are steadily moving us in the direction of the day when ordering up a new organ may be as tedious as ordering an MRI is in our day. One of the hurdles in creating lab-grown organs, yet, is that the cells in such a structure require a way to obtain nutrients. Researchers at Vanderbilt University (VU) may have just leaped that hurdle via a many unexpected tool – a cotton candy machine.
Leon Bellan, an assistant professor of mechanical engineering at VU, has in fact been tinkering with cotton candy machines for a few time after realizing the machines were ideal at spinning out small threads that resembled human capillaries.
“I went to Target and bought a cotton candy machine for of US$40,” Bellan said. “It turned out that it created threads that were of one tenth the diameter of a human hair – roughly the same dimensions as capillaries – so they may be utilized to manufacture channel structures in other materials.”
The issue, yet, is that if the threads are spun out of sugar, if attempts were created to implant them in a hydrogel that’s utilized to grow organ tissue, they’d just dissolve as soon as the gel touched them. What was requireed was a substance that may hold up against the water-based gel first, and can and so be triggered to dissolve after the gel is in place, leaving behind small channels.
Bellan and his team discovered that a polymer called PNIPAM – or Poly (N-isopropylacrylamide) – was the ideal material for the job as it is just soluble at a lower place 32° C (90° F). To take advantage of this property, the researchers spun out a few PNIPAM threads via a machine quite much like to a cotton candy machine, and so immersed them in gelatin, that was kept warm in an incubator set at 37° C (99° F). Once the gelatin had set, it was cooled to room temperature, that cautilized the threads to dissolve, leaving behind small tubes.
Those tubes were and so pumped full of cells along with the nutrients they requireed to grow. Bellan reported that after a week, 90 percent of the cells in the tubes were alive and functional.
This method has a distinct advantage over another common method of creating capillaries in gels, known as the “bottom-up” process. In such a process, cells are cultured in the gel and some day spontaneously grow their own capillaries. But the process takes time, that means that new layers can’t be placed into the budding tissue preceding the capillaries are created for the reason there’s a accident the cells in the middle of the structure may die off.
Because Bellan’s method, known as a “top-down” approach, can form the capillaries all at once, thicker tissue structures may theoretically be possible.
“Some folks in the field ponder this approach is a little crazy,” said Bellan, “But now we’ve shown we can use this easy technique to manufacture microfluidic networks that mimic the three-dimensional capillary process in the human body in a cell-friendly style. Generally, it is not that complex to manufacture two-dimensional networks, but adding the third dimension is much harder; with this approach, we can manufacture our process as three-dimensional as we like.”
Bellan and his colleagues are now looking into ways to tailor the process to mimic capillaries in different types of types of tissues. “Our goal is to turn it into a basic ‘toolbox’ that can allow other researchers to use this easy, affordable approach to turn it into the artificial vasculature requireed to assist artificial livers, kidneys, bone and other organs,” he said.
And how does a man who’s spent so much time around cotton candy feel of the sticky substance? “People always ask if I like cotton candy,” he says in the video at a lower place. “I ponder it is kind of disgusting.”
The team’s research was published online in the journal Advanced Healthcare Materials on February 4.
Source: Vanderbilt University
by admin • March 5, 2017
by admin • November 28, 2016
by admin • November 28, 2016