title: Engrafting costimulator molecules onto tumor cell surfaces with chelator lipids: a potentially convenient approach in cancer vaccine development.
abstract: The genetic modification of cells to develop cell-based vaccines and to modulate immune responses in vivo can be risky and inconvenient to perform in clinical situations. A novel chelator lipid, nitrilotriacetic acid di-tetradecylamine (NTA-DTDA) that, via the NTA group has high affinity for 6His peptide, was used to directly anchor recombinant forms of T cell costimulatory molecules containing a C-terminal 6-His sequence onto tumor cell surfaces. Initial experiments using murine P815 tumor cells established the optimum conditions for incorporating NTA-DTDA onto the membranes of cells. P815 cells with incorporated NTA-DTDAbound hexahistidine-(6His)-tagged forms of the extracellular domains of murine B7.1 and CD40 (B7.1-6H and CD40-6H) at very high levels (fluorescence 200-300-fold above background), and both proteins could be anchored onto the cells simultaneously. Significant loss of the anchored or "engrafted" protein occurred through membrane internalization following culture of the cells under physiological conditions, but P815 cells with engrafted B7.1-6H and/or CD40-6H stimulated the proliferation of allogenic and syngeneic splenic T cells in vitro, and generated cytotoxic T cells when used as vaccines in syngeneic animals. Furthermore, the immunization of syngeneic mice with P815 cells engrafted with B7.1-6H or with B7. 1-6H and CD40-6H induced protection against challenge with the native P815 tumor. The results indicate that the use of chelator lipids like NTD-DTDA to engraft costimulatory and/or other molecules onto cell membranes could provide a convenient alternative to transfection in the development of cell-based vaccines and for modulation of immune function.
authors.affiliation: Division of Biochemistry and Molecular Biology, School of Life Sciences, Faculty of Science, Australian National University, Canberra, Australia.
authors.forename: C L
authors.initials: CL
authors.lastname: van Broekhoven
authors.forename: C R
authors.initials: CR
authors.lastname: Parish
authors.forename: G
authors.initials: G
authors.lastname: Vassiliou
authors.forename: J G
authors.initials: JG
authors.lastname: Altin
mesh_terms: D000588:Amines / Q000378:metabolism; D000818:Animals; D018122:B7-1 Antigen / Q000235:genetics / Q000276:immunology / Q000378:metabolism; D019013:CD40 Antigens / Q000235:genetics / Q000276:immunology / Q000378:metabolism; D019496:Cancer Vaccines / Q000737:chemistry / Q000276:immunology*; D002455:Cell Division / Q000235:genetics / Q000276:immunology; D002462:Cell Membrane / Q000235:genetics / Q000276:immunology / Q000378:metabolism; D002614:Chelating Agents / Q000378:metabolism; D003602:Cytotoxicity, Immunologic / Q000235:genetics; D005260:Female; D006639:Histidine / Q000235:genetics / Q000378:metabolism; D008213:Lymphocyte Activation / Q000235:genetics; D008297:Male; D012515:Mast-Cell Sarcoma / Q000235:genetics / Q000276:immunology* / Q000378:metabolism* / Q000473:pathology; D051379:Mice; D008810:Mice, Inbred C57BL; D008811:Mice, Inbred DBA; D018613:Microscopy, Confocal; D009571:Nitrilotriacetic Acid / Q000031:analogs & derivatives / Q000378:metabolism; D011485:Protein Binding / Q000235:genetics; D013601:T-Lymphocytes / Q000276:immunology / Q000378:metabolism; D014407:Tumor Cells, Cultured
chemical_list: D000588:Amines; D018122:B7-1 Antigen; D019013:CD40 Antigens; D019496:Cancer Vaccines; D002614:Chelating Agents; C405382:nitrilotriacetic acid ditetradecylamine; D006639:Histidine; D009571:Nitrilotriacetic Acid