title: Protein transfer of the costimulatory molecule, B7-2 (CD86), into tumor membrane liposomes as a novel cell-free vaccine.
abstract: Several approaches have been taken to enhance the immunogenicity of tumors. Genetically-modified tumors expressing various cytokines, major histocompatibility complex (MHC) molecules, or costimulatory molecules such as B7-1 (CD80) or B7-2 (CD86) can induce tumor-specific immune responses. In the present study, an alternative approach was explored based on direct protein transfer of purified recombinant B7-2 into tumor cell membranes. B7-2 was purified from recombinant baculovirus infected insect cells. Although differentially glycosolyated, the recombinant B7-2 retained the function to costimulate T-cell proliferation. Purified B7-2 was readily incorporated into tumor membranes using a detergent dialysis technique to form unilameller liposomes. The immunogenicity of tumor membrane proteoliposomes was significantly increased by incorporation of B7-2. These findings suggest an alternative method for the introduction of immunostimulatory molecules into tumor membranes to create novel tumor vaccines.
authors.affiliation: Department of Pathology and Laboratory Medicine, 7309 WMRB, Emory University School of Medicine, Atlanta, GA, USA.
authors.forename: L E
authors.initials: LE
authors.lastname: Westerman
authors.forename: P E
authors.initials: PE
authors.lastname: Jensen
mesh_terms: D000276:Adjuvants, Immunologic / Q000008:administration & dosage / Q000302:isolation & purification; D000818:Animals; D015703:Antigens, CD / Q000008:administration & dosage* / Q000302:isolation & purification; D051940:B7-2 Antigen; D016367:Baculoviridae / Q000235:genetics; D016466:CHO Cells; D019496:Cancer Vaccines / Q000008:administration & dosage* / Q000302:isolation & purification; D002460:Cell Line; D006224:Cricetinae; D007114:Immunization; D007313:Insecta; D008081:Liposomes; D008562:Membrane Glycoproteins / Q000008:administration & dosage* / Q000302:isolation & purification; D051379:Mice; D008807:Mice, Inbred BALB C; D011994:Recombinant Proteins / Q000008:administration & dosage / Q000302:isolation & purification; D014162:Transfection; D014407:Tumor Cells, Cultured
chemical_list: D000276:Adjuvants, Immunologic; D015703:Antigens, CD; D051940:B7-2 Antigen; D019496:Cancer Vaccines; C497965:Cd86 protein, mouse; D008081:Liposomes; D008562:Membrane Glycoproteins; D011994:Recombinant Proteins