NK cells switch from granzyme B to death receptor-mediated cytotoxicity during serial killing.

Prager I, Liesche C, van Ooijen H, Urlaub D, Verron Q, Sandström N, Fasbender F, Claus M, Eils R, Beaudouin J, Önfelt B, Watzl C

J. Exp. Med. 216 (9) 2113-2127 [2019-09-02; online 2019-07-03]

NK cells eliminate virus-infected and tumor cells by releasing cytotoxic granules containing granzyme B (GrzB) or by engaging death receptors that initiate caspase cascades. The orchestrated interplay between both cell death pathways remains poorly defined. Here we simultaneously measure the activities of GrzB and caspase-8 in tumor cells upon contact with human NK cells. We observed that NK cells switch from inducing a fast GrzB-mediated cell death in their first killing events to a slow death receptor-mediated killing during subsequent tumor cell encounters. Target cell contact reduced intracellular GrzB and perforin and increased surface-CD95L in NK cells over time, showing how the switch in cytotoxicity pathways is controlled. Without perforin, NK cells were unable to perform GrzB-mediated serial killing and only killed once via death receptors. In contrast, the absence of CD95 on tumor targets did not impair GrzB-mediated serial killing. This demonstrates that GrzB and death receptor-mediated cytotoxicity are differentially regulated during NK cell serial killing.

PubMed 31270246

DOI 10.1084/jem.20181454

Crossref 10.1084/jem.20181454

pmc: PMC6719417
pii: jem.20181454


Publications 9.5.1