Overexpression of IL-15 in vivo enhances Tc1 response, which inhibits allergic inflammation in a murine model of asthma.
IL-15, a pleiotropic cytokine, is involved in the inflammatory responses in various infectious and autoimmune diseases. We have recently constructed IL-15-transgenic (Tg) mice, which have an increased number of memory-type CD8+ T cells in the peripheral lymphoid tissues. In the present study, we found that eosinophilia and Th2-type cytokine production in the airway were severely attenuated in OVA-sensitized IL-15-Tg mice following OVA inhalation. IL-15-Tg mice preferentially developed Tc1 responses mediated by CD8+ T cells after OVA sensitization, and in vivo depletion of CD8+ T cells by anti-CD8 mAb aggravated the allergic airway inflammation in IL-15-Tg mice following OVA inhalation. Adoptive transfer of CD8+ T cells from OVA-sensitized IL-15-Tg mice into normal mice before OVA sensitization suppressed Th2 response to OVA in the normal mice. These results suggest that overexpression of IL-15 in vivo suppresses Th2-mediated-allergic airway response via induction of CD8+ T cell-mediated Tc1 response.
Ishimitsu
R
R
Laboratory of Host Defense and Germfree Life, Research Institute for Disease Mechanism and Control, Nagoya University School of Medicine, Nagoya, Japan.
Nishimura
H
H
Yajima
T
T
Watase
T
T
Kawauchi
H
H
Yoshikai
Y
Y
D019264:Adoptive Transfer; D000485:Allergens / Q000008:administration & dosage / Q000276:immunology*; D000818:Animals; D001249:Asthma / Q000235:genetics / Q000276:immunology / Q000473:pathology / Q000517:prevention & control*; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology* / Q000378:metabolism* / Q000637:transplantation; D004195:Disease Models, Animal; D007108:Immune Tolerance / Q000235:genetics; D007114:Immunization; D007073:Immunoglobulin E / Q000096:biosynthesis; D007249:Inflammation / Q000276:immunology / Q000517:prevention & control; D007274:Injections, Intraperitoneal; D019409:Interleukin-15 / Q000096:biosynthesis* / Q000235:genetics / Q000502:physiology; D008168:Lung / Q000276:immunology / Q000473:pathology*; D008212:Lymphocyte Depletion; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D008822:Mice, Transgenic; D010047:Ovalbumin / Q000008:administration & dosage / Q000276:immunology; D016176:T-Lymphocyte Subsets / Q000276:immunology* / Q000378:metabolism* / Q000637:transplantation
D000485:Allergens; D019409:Interleukin-15; D007073:Immunoglobulin E; D010047:Ovalbumin