Pre-Existing Immunity to CRISPR Found in 96% of People in Study.
(Cas9 from S. pyogenes is one of the most common DNA-cutting enzymes used in CRISPR R&D, if not the most commonly used.).
The researchers found that 96 percent of the people in the study had T-cell based immunity against Cas9, and 85% had antibodies against it.
Michael Schmueck-Henneresse of Charité University Medicine Berlin, who led today’s study, said that he was initially surprised by the 96% finding.
Intellia Therapeutics says it has been on the lookout for T-cell based immunity against its CRISPR system.
Other researchers have also raised a red flag around another CRISPR effect: unintended edits in off-target spots along the genome. »