The DOI matches its Crossref record; 21 of the 21 references it cites were found in a registry or an index.
IL-21 Is Required to Control Chronic Viral Infection
Open accessAbstract
Controlling Chronic Viral Infections: Chronic viral infections such as HIV and hepatitis B and C viruses are major public health concerns. T cell—mediated immune responses are critical for controlling viral infections. In contrast to acute infections, chronic viral infections are characterized by “exhausted” cytotoxic CD8 + T cells, cells which exhibit reduced proliferative capacity, cytokine secretion, and cytotoxicity. Treatments that reverse exhaustion result in increased viral control. Despite their exhaustion, these CD8 + T cells eventually help to control chronic infections by killing virally infected cells, and require CD4 + T cell help to do so. How do CD4 + T cells provide help to CD8 + T cells during chronic infection (see the Perspective by Johnson and Jameson )? Elsaesser et al. (p. 1569 , published online 7 May), Yi et al. (p. 1572 , published online 14 May), and Fröhlich et al. (p. 1576 , published online 28 May) now show that the cytokine, interleukin-21 (IL-21), known to be critical for the differentiation of certain CD4 + T cell effector subsets, is an essential factor produced by CD4 + T cells that helps CD8 + T cells to control chronic lymphocytic choriomeningitis virus infection in mice. Acute and chronic infections resulted in differing amounts of IL-21 production by virus-specific CD4 + T cells. CD8 + T cells required IL-21 directly, and when CD8 + T cells were unable to signal through IL-21 or IL-21 was not available, they were reduced in number, exhibited a more exhausted phenotype, and were not able to control the virus. In contrast, the absence of IL-21–dependent signaling did not affect primary CD8 + T cell responses to acute infection or responses to a viral rechallenge, suggesting that differentiation of memory CD8 + T cells is independent of IL-21.
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Cites
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Cited by
Molecular and cellular insights into T cell exhaustion
Wherry, E. J., & Kurachi, M. (2015) · Nature Reviews Immunology · doi:10.1038/nri3862 · Cited by 4,652
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HIV and Tuberculosis: a Deadly Human Syndemic
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Metadata
- Authors
- Elsaesser, H., Sauer, K., & Brooks, D. G.
- Venue
- Science
- Published
- 2009-06-19
- Volume
- 324
- Issue
- 5934
- Pages
- 1569-1572
- ISSN
- 0036-8075 (ISSN-L)
- 1095-9203
- OpenAlex
- W2073449362
- Cited by
- 554
- References
- 21
- FWCI
- 21.38
- Type
- journal article
- Language
- en
- Open access
- green
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