Autophagy promotes T-cell survival through degradation of proteins of the cell death machinery.
Cell Death Differ 2012;
19:144-52. [PMID:
21660048 PMCID:
PMC3252822 DOI:
10.1038/cdd.2011.78]
[Citation(s) in RCA: 165] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2010] [Revised: 04/11/2011] [Accepted: 05/02/2011] [Indexed: 12/14/2022] Open
Abstract
Autophagy is implicated in regulating cell death in activated T cells, but the underlying mechanism is unclear. Here, we show that inhibition of autophagy via Beclin 1 gene deletion in T cells leads to rampant apoptosis in these cells upon TCR stimulation. Beclin 1-deficient mice fail to mount autoreactive T-cell responses and are resistant to experimental autoimmune encephalomyelitis. Compared with Th17 cells, Th1 cells are much more susceptible to cell death upon Beclin 1 deletion. Cell death proteins are highly increased in Beclin 1-deficient T cells and inhibition of caspases and genetic deletion of Bim reverse apoptosis. In addition, p62/sequestosome 1 binds to caspase-8 but does not control levels of procaspase-8 or other cell death-related proteins. These results establish a direct role of autophagy in inhibiting the programmed cell death through degradation of apoptosis proteins in activated T cells.
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