| Abstract: |
Receptor-interacting protein kinase 3 (RIP3) and its substrate mixed-lineage kinase domain-like protein (MLKL) are core regulators of programmed necrosis. The elimination of pathogen-infected cells by programmed necrosis acts as an important host defense mechanism. Here, we report that human herpes simplex virus 1 (HSV-1) and HSV-2 had opposite impacts on programmed necrosis in human cells versus their impacts in mouse cells. Similar to HSV-1, HSV-2 infection triggered programmed necrosis in mouse cells. However, neither HSV-1 nor HSV-2 infection was able to induce programmed necrosis in human cells. Moreover, HSV-1 or HSV-2 infection in human cells blocked tumor necrosis factor (TNF)-induced necrosis by preventing the induction of an RIP1/RIP3 necrosome. The HSV ribonucleotide reductase large subunit R1 was sufficient to suppress TNF-induced necrosis, and its RIP homotypic interaction motif (RHIM) domain was required to disrupt the RIP1/RIP3 complex in human cells. Therefore, this study provides evidence that HSV has likely evolved strategies to evade the host defense mechanism of programmed necrosis in human cells. © 2015, American Society for Microbiology. |
