Article

NK Cell Maturation and Function in C57BL/6 Mice Are Altered by Caloric Restriction

Department of Food Science and Human Nutrition, Michigan State University, East Lansing, MI 48824.
The Journal of Immunology (Impact Factor: 4.92). 12/2012; 190(2). DOI: 10.4049/jimmunol.1201837
Source: PubMed

ABSTRACT

NK cells are a heterogenous population of innate lymphocytes with diverse functional attributes critical for early protection from viral infections. We have previously reported a decrease in influenza-induced NK cell cytotoxicity in 6-mo-old C57BL/6 calorically restricted (CR) mice. In the current study, we extend our findings on the influence of CR on NK cell phenotype and function in the absence of infection. We demonstrate that reduced mature NK cell subsets result in increased frequencies of CD127(+) NK cells in CR mice, skewing the function of the total NK cell pool. NK cells from CR mice produced TNF-α and GM-CSF at a higher level, whereas IFN-γ production was impaired following IL-2 plus IL-12 or anti-NK1.1 stimulation. NK cells from CR mice were highly responsive to stimulation with YAC-1 cells such that CD27(-)CD11b(+) NK cells from CR mice produced granzyme B and degranulated at a higher frequency than CD27(-)CD11b(+) NK cells from ad libitum fed mice. CR has been shown to be a potent dietary intervention, yet the mechanisms by which the CR increases life span have yet to be fully understood. To our knowledge, these findings are the first in-depth analysis of the effects of caloric intake on NK cell phenotype and function and provide important implications regarding potential ways in which CR alters NK cell function prior to infection or cancer.

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Available from: Eleni Beli, Dec 23, 2015
    • "NK cells, the third population of lymphocytes, are also strongly affected by malnutrition. Although not much is known about the metabolic status of NK cells, it has been shown that prolonged caloric restriction in mice results in decreased NK cell numbers and production of IFN and impairs NK-cell dependent responses to influenza virus infection[184,185]. The effects of starvation on leukocyte biology do not appear to be the direct result of a shortage of nutrients, but of an inability to use nutrients in the absence of certain endocrine signals from adipose tissue, in particular leptin. "
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    • "For NK cells, this concept might be expandable to additional immunosuppressive mechanisms. A recent study suggested that calorically restricted mice, which have increased levels of corticosteroids, display increased frequencies of CD127 + NK cells as a consequence of a reduction of mature NK cells (Clinthorne et al., 2013). "
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