However, LYST CRISPR NK92mi cells contained granules that were positive for perforin but negative for LAMP1 or LAMP2 and vice versa, with nearly all the granules positive for CI-MPR and many acquiring low levels of EEA-1, like NK cells from patients with CHS (Fig 1, F). This evidence concerns the gene PRF1 and Chediak-Higashi syndrome.