IL-2-induced activation-induced cell death is inhibited in IL-15 transgenic mice.
A transgenic (Tg) mouse expressing human IL-15 was generated to define the role of IL-15 in the normal immune response. Overexpression of IL-15 resulted in an increase of NK, CD44(hi)CD8 memory T cells, and gammadelta T cells. Additionally, we observed the emergence of a novel type of NK-T cells with CD8alphaalpha' expression. Due to the expansion and activation of NK cells, the IL-15Tg mouse showed enhanced innate immunity. In adaptive T cell immunity, the roles of IL-15 contrasted with those of IL-2. IL-15 inhibited IL-2-induced T cell death, which plays a role in the maintenance of peripheral self-tolerance. IL-15 thus seems to contribute to enhanced immune memory by selectively propagating memory T cells and by blocking T cell death mediated by IL-2.
Marks-Konczalik
J
J
Metabolism Branch, Division of Clinical Sciences, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA.
Dubois
S
S
Losi
J M
JM
Sabzevari
H
H
Yamada
N
N
Feigenbaum
L
L
Waldmann
T A
TA
Tagaya
Y
Y
D000818:Animals; D015496:CD4-Positive T-Lymphocytes / Q000166:cytology / Q000276:immunology; D018414:CD8-Positive T-Lymphocytes / Q000166:cytology / Q000276:immunology; D002453:Cell Cycle; D016923:Cell Death / Q000502:physiology*; D016207:Cytokines / Q000096:biosynthesis; D006801:Humans; D019409:Interleukin-15 / Q000235:genetics / Q000502:physiology*; D007376:Interleukin-2 / Q000502:physiology*; D007694:Killer Cells, Natural / Q000166:cytology / Q000276:immunology; D018655:Lymphocyte Count; D051379:Mice; D008822:Mice, Transgenic; D019076:Transgenes
D016207:Cytokines; D019409:Interleukin-15; D007376:Interleukin-2