RIPK1 and NF-κB signaling in dying cells determines cross-priming of CD8+ T cells

Link to Pubmed [PMID] – 26405229

Science. 2015 Sep 24. pii: aad0395. [Epub ahead of print]

Dying cells initiate adaptive immunity by providing both antigens and inflammatory stimuli for dendritic cells (DCs), which in turn activate CD8⁺ T cells through a process called antigen cross-priming. To define how different forms of programmed cell death influence immunity, we established models of necroptosis and apoptosis, where dying cells are generated by RIPK3 and CASP8 dimerization, respectively. We found that release of inflammatory mediators such as damage-associated molecular patterns (DAMPs) by dying cells was not sufficient for CD8⁺ T cell cross-priming. Instead, robust cross-priming required RIPK1 signaling and NF-κB-induced transcription within dying cells. Decoupling NF-κB signaling from necroptosis or inflammatory apoptosis reduced priming efficiency and tumor immunity. Our results reveal that coordinated inflammatory and cell death signaling pathways within dying cells orchestrate adaptive immunity.