Scientific silver bullets are rare, but the genome-editing technology know as CRISPR definitely qualifies. This technology may even make it too easy to alter genetic information — leading to ethical concerns about its use in what was previously the very difficult task of editing human embryos.
While those concerns are certainly justified, using CRISPR in humans is by no means an inherently bad idea. A group of scientists just published a paper in the journal Proceedings of the National Academy of Sciences, which demonstrates how this powerful technology could be used to fight devastating diseases, by editing cells found in the human immune system called T cells. By manipulating the genes found within these cells, the researchers found that they can make them less susceptible to HIV infection and even cancer.
"This is not a matter of engineering human embryos — that's a line that needs to be respected," said senior study author Alexander Marson of the University of California, San Francisco to Tech Times. "The beauty of this is that we're working with the immune system, and T cells can be isolated from blood."
T cells are key coordinating cells in the immune system. They essentially set the stage for determining how the immune system will respond to infections, and have been found to be central to a lot of different disease processes.
Since T cells are such a critical part of the immune system, scientists – including Marson and his group – have been looking into their genomes for years.
"What we've really needed is a way to go in and either delete or replace parts of the genome in T cells, and then test the effects of specific parts of the genome. And we haven't had the tools to do that," said Marson. "Now, all of a sudden, this application of CRISPR potentially changes that."
CRISPR is cutting-edge technology that scientists borrowed from some of the most ancient organisms on the planet: bacteria. As single-celled organisms, bacteria don't have an immune system composed of a fleet of specialized cells like humans do. Instead, they have CRISPR — an incredibly clever sequence of genetic information that allows the bacterium to recognize and destroy foreign genetic material from viruses to prevent infection.
In the past several years, scientists have figured out a way to turn this ingenious natural system into a powerful tool for genetic engineering. CRISPR, which stands for clustered regularly interspaced short palindromic repeats, allows researchers to can go in and either delete or cut-and-paste pieces of genome within living cells with remarkable precision.
"We have this unprecedented potential to study how the genome is organized, in a way that allows T cells to have these specialized functions," Marson said. "And that could open up a lot of doors for thinking about more precise ways of developing drugs for immune system-related diseases."
For this study, Marson and his colleagues used CRISPR to eliminate a gene that encodes a particular protein on the surface of T cells. The HIV virus uses this protein as a way to gain access to T cells and infect them, so the application may one day be used to fight off this deadly virus. To make sure that their method of applying CRISPR technology to T cells works, they also tested it on a second gene that is involved in tumor development.
This new system will need to undergo further testing to ensure that it is safe to use in humans, but its potential is immense.
"This is something that I think really connects centrally to human health," Marson said.
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