title: Membrane-bound TRAIL supplements natural killer cell cytotoxicity against neuroblastoma cells.
abstract: Neuroblastoma cells have been reported to be resistant to death induced by soluble, recombinant forms of tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) (CD253/TNFSF10) because of low or absent expression of caspase-8 and/or TRAIL-receptor 2 (TRAIL-R2/DR5/CD262/TNFRSF10b). However, their sensitivity to membrane-bound TRAIL on natural killer (NK) cells is not known. Comparing microarray gene expression and response to NK cell-mediated cytotoxicity, we observed a correlation between TRAIL-R2 expression and the sensitivity of 14 neuroblastoma cell lines to the cytotoxicity of NK cells activated with interleukin (IL)-2 plus IL-15. Even though most NK cytotoxicity was dependent upon perforin, the cytotoxicity was supplemented by TRAIL in 14 of 17 (82%) neuroblastoma cell lines as demonstrated using an anti-TRAIL neutralizing antibody. Similarly, a recently developed NK cell expansion system employing IL-2 plus lethally irradiated K562 feeder cells constitutively expressing membrane-bound IL-21 (K562 clone 9.mbIL21) resulted in activated NK cells derived from normal healthy donors and neuroblastoma patients that also utilized TRAIL to supplement cytotoxicity. Exogenous interferon-γ upregulated expression of caspase-8 in 3 of 4 neuroblastoma cell lines and increased the contribution of TRAIL to NK cytotoxicity against 2 of the 3 lines; however, relatively little inhibition of cytotoxicity was observed when activated NK cells were treated with an anti-interferon-γ neutralizing antibody. Constraining the binding of anti-TRAIL neutralizing antibody to membrane-bound TRAIL but not soluble TRAIL indicated that membrane-bound TRAIL alone was responsible for essentially all of the supplemental cytotoxicity. Together, these findings support a role for membrane-bound TRAIL in the cytotoxicity of NK cells against neuroblastoma cells.
authors.affiliation: Division of Hematology/Oncology, Children's Hospital Los Angeles, Keck School of Medicine, University of Southern California, Los Angeles, CA 90027, USA. msheard@chla.usc.edu
authors.forename: Michael A
authors.initials: MA
authors.lastname: Sheard
authors.forename: Shahab
authors.initials: S
authors.lastname: Asgharzadeh
authors.forename: Yin
authors.initials: Y
authors.lastname: Liu
authors.forename: Tsen-Yin
authors.initials: TY
authors.lastname: Lin
authors.forename: Hong-Wei
authors.initials: HW
authors.lastname: Wu
authors.forename: Lingyun
authors.initials: L
authors.lastname: Ji
authors.forename: Susan
authors.initials: S
authors.lastname: Groshen
authors.forename: Dean A
authors.initials: DA
authors.lastname: Lee
authors.forename: Robert C
authors.initials: RC
authors.lastname: Seeger
mesh_terms: D019138:Antibodies, Blocking / Q000494:pharmacology; D017209:Apoptosis / Q000187:drug effects; D053181:Caspase 8 / Q000235:genetics / Q000378:metabolism; D048708:Cell Growth Processes / Q000187:drug effects; D016207:Cytokines / Q000276:immunology; D003602:Cytotoxicity, Immunologic / Q000187:drug effects; D015972:Gene Expression Regulation, Neoplastic / Q000187:drug effects; D006801:Humans; D020014:K562 Cells; D007694:Killer Cells, Natural / Q000187:drug effects* / Q000276:immunology; D008213:Lymphocyte Activation / Q000187:drug effects; D008565:Membrane Proteins / Q000276:immunology / Q000378:metabolism*; D046228:Microarray Analysis; D009447:Neuroblastoma / Q000188:drug therapy* / Q000276:immunology; D053220:Receptors, TNF-Related Apoptosis-Inducing Ligand / Q000235:genetics / Q000378:metabolism*; D053221:TNF-Related Apoptosis-Inducing Ligand / Q000276:immunology / Q000378:metabolism*; D059467:Transcriptome
chemical_list: D019138:Antibodies, Blocking; D016207:Cytokines; D008565:Membrane Proteins; D053220:Receptors, TNF-Related Apoptosis-Inducing Ligand; D053221:TNF-Related Apoptosis-Inducing Ligand; D053181:Caspase 8