title: Role of trans-cellular IL-15 presentation in the activation of NK cell-mediated killing, which leads to enhanced tumor immunosurveillance.
abstract: Interleukin 15 (IL-15) is a critical factor for the proliferation and activation of natural killer (NK) and CD8 T cells. Recently, we demonstrated that IL-15Ralpha expressed on monocytes/dendritic cells captures and presents IL-15 to neighboring cells in trans (trans-presentation of IL-15) through cell-cell contact. In the current study, we provide evidence that the IL-15 presented in trans, but not soluble IL-15 at physiologic concentrations, augments the killing activity mediated by NK cells in vitro. In addition, transfection of IL-15Ralpha into a colon carcinoma cell line (MC38) enabled these cells to present IL-15 in trans to NK cells and augmented their killing activity, resulting in the efficient lysis of MC38 cells by NK cells in vitro. Furthermore, these transfected MC38 cells no longer form fatal pulmonary metastases in mice. It was also shown that NK cells play an important role in the rejection of MC38 cells under these circumstances. These results collectively suggest that the IL-15 trans-presentation mechanism operates in vivo to augment the tumor immune surveillance mechanism. Furthermore, our observation provides the scientific basis for a novel strategy to prevent cancer development/metastasis.
authors.affiliation: Metabolism Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA.
authors.forename: Hisataka
authors.initials: H
authors.lastname: Kobayashi
authors.forename: Sigrid
authors.initials: S
authors.lastname: Dubois
authors.forename: Noriko
authors.initials: N
authors.lastname: Sato
authors.forename: Helen
authors.initials: H
authors.lastname: Sabzevari
authors.forename: Yoshio
authors.initials: Y
authors.lastname: Sakai
authors.forename: Thomas A
authors.initials: TA
authors.lastname: Waldmann
authors.forename: Yutaka
authors.initials: Y
authors.lastname: Tagaya
mesh_terms: D000818:Animals; D017951:Antigen Presentation / Q000276:immunology*; D002455:Cell Division / Q000276:immunology; D045744:Cell Line, Tumor; D003110:Colonic Neoplasms / Q000276:immunology* / Q000473:pathology; D006084:Graft Rejection / Q000276:immunology; D019409:Interleukin-15 / Q000276:immunology* / Q000378:metabolism; D007694:Killer Cells, Natural / Q000276:immunology* / Q000378:metabolism; D008175:Lung Neoplasms / Q000276:immunology / Q000556:secondary; D051379:Mice; D008810:Mice, Inbred C57BL; D008822:Mice, Transgenic; D009368:Neoplasm Transplantation; D053647:Receptors, Interleukin-15; D015375:Receptors, Interleukin-2 / Q000235:genetics; D014162:Transfection
chemical_list: C508025:Il15ra protein, mouse; D019409:Interleukin-15; D053647:Receptors, Interleukin-15; D015375:Receptors, Interleukin-2