Selective chemical functional probes of granzymes A and B reveal granzyme B is a major effector of natural killer cell-mediated lysis of target cells.
The mechanism of target cell lysis in cytotoxic lymphocyte-mediated death is not well understood, and the role of granzymes in this process is unclear. Chemical functional probes were thus prepared for the major granzymes A and B to deconvolute their role in natural killer cell-mediated lysis of target cells. These biotinylated and substrate specificity-based diphenyl phosphonates allowed facile evaluation of selectivity through activity-based profiling in cell lysates and intact cells. Both inhibitors were found to be extremely selective in vitro and in cells. Use of these inhibitors in cell-based assays revealed granzyme A to be a minor effector and granzyme B to be a major effector of target cell lysis by natural killer cells. These studies indicate that the proapoptotic granzyme B functions also as a pronecrotic effector of target cell death.
Mahrus
Sami
S
Chemistry and Chemical Biology Graduate Program, University of California, San Francisco, San Francisco, California 94143, USA.
Craik
Charles S
CS
D017209:Apoptosis; D001360:Avidin / Q000378:metabolism; D016923:Cell Death; D002460:Cell Line; D053804:Granzymes; D006801:Humans; D020014:K562 Cells; D007694:Killer Cells, Natural / Q000201:enzymology*; D009943:Organophosphorus Compounds / Q000138:chemical synthesis / Q000494:pharmacology; D012697:Serine Endopeptidases / Q000378:metabolism*; D015842:Serine Proteinase Inhibitors / Q000138:chemical synthesis / Q000494:pharmacology*
D009943:Organophosphorus Compounds; D015842:Serine Proteinase Inhibitors; D001360:Avidin; C509213:GZMB protein, human; D053804:Granzymes; D012697:Serine Endopeptidases; C509212:GZMA protein, human