NK cells controlling virus-specific T cells: Rheostats for acute vs. persistent infections

Department of Pathology and Program for Immunology and Virology, University of Massachusetts Medical School, 55 Lake Avenue North, Worcester, MA 01655, USA. Electronic address: .
Virology (Impact Factor: 3.32). 01/2013; 435(1):37-45. DOI: 10.1016/j.virol.2012.10.005
Source: PubMed


Viral infections characteristically induce a cytokine-driven activated natural killer (NK) cell response that precedes an antigen-driven T cell response. These NK cells can restrain some but not all viral infections by attacking virus-infected cells and can thereby provide time for an effective T cell response to mobilize. Recent studies have revealed an additional immunoregulatory role for the NK cells, where they inhibit the size and functionality of the T cell response, regardless of whether the viruses are themselves sensitive to NK cells. This subsequent change in T cell dynamics can alter patterns of immunopathology and persistence and implicates NK cells as rheostat-like regulators of persistent infections.


Available from: Stephen N Waggoner
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    • "The priming of Th1 cells is crucial for the generation and expansion of cytotoxic T lymphocytes (CTLs) and survival of CD8 + memory T cells, which are in turn able to kill infected or cancer cells (Kennedy and Celis 2008). NK cells also serve an important role in regulating DCmediated adaptive immune responses (Kalinski and others 2005a; Marcenaro and others 2006; Welsh and Waggoner 2013). Classically, NK cells are not only involved in the direct early control of viral infections and tumor immunosurveillance (Smyth and others 2002; Andrews and others 2003; Lee and others 2007) but NK cells also indirectly provide help by interacting with DCs at the site of inflammation or in the lymph nodes (Moretta 2002). "
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    • "Natural killer (NK) cells are a subset of innate lymphoid cells that function as early controllers of viral infections (Welsh and Waggoner, 2013). Recently the roles of NK cells in restricting the induction of adaptive anti-viral T cell responses and abetting the development of exhaustion have been highlighted (Fig. 2). "
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    Virology 01/2015; 361. DOI:10.1016/j.virol.2014.12.033 · 3.32 Impact Factor
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