“We’re removing the doorway that HIV uses to get into cells”

From Time online…

Natural immunity is the most reliable way to protect yourself from viruses, bacteria and parasites. And the best way to acquire such immunity, in most cases, is to expose your immune system to the bug in question—either by getting infected or getting immunized. Until now, such protection was only possible with diseases like chicken pox or polio. But now, scientists at Harvard University say that people might soon arm themselves against HIV in a similar way, but through a different method.

Chad Cowan and Derrick Rossi, both in the department of stem cell and regenerative biology at Harvard University, and their colleagues report in the journal Cell Stem Cell that they have successfully edited the genomes of blood cells to make them impervious to HIV. In order survive, HIV needs to insert its genome into that of a healthy cell, and to infect these cells, HIV latches onto a protein on their surface called CCR5. If CCR5 is mutated, however, it’s as if the locks have been changed and HIV no longer has the right key; it can’t attach itself and the cells are protected from infection. So the scientists tried a new gene editing technique called CRISPR that allows them to precisely snip out parts of a cell’s genome, and they spliced out the CCR5 gene. To their surprise, the technique was relatively efficient, transforming about half of the cells they treated with CRISPR into CCR5-free, or HIV-resistant, cells.

Continue reading on Time.com.