title: Liposomes containing muramyl tripeptide phosphatidylethanolamine (MTP-PE) are excellent adjuvants for induction of an immune response to protein and tumor antigens.
abstract: Liposomes containing the synthetic lipophilic analog of muramyl dipeptide, muramyl tripeptide phosphatidylethanolamine (MTP-PE), were used as adjuvants for the induction of humoral and cellular immune responses following immunization with protein or tumor antigens. Cellular immune reactions, including delayed-type hypersensitivity and lymphoproliferation in vitro, were observed following immunization of mice with a mixture of antigen and liposome-MTP-PE. Immunization with murine melanoma K1735 cells, admixed with liposomal MTP-PE, induced a protective immune response as demonstrated by the rejection of transplanted tumor cells. Antibody production was also induced following immunization with protein antigens admixed with liposome-MTP-PE. The efficacy of adjuvant activity following immunization with antigens admixed with liposome-MTP-PE was equal to or better than that of complete Freund's adjuvant (CFA). Moreover, liposome-MTP-PE did not have the toxic side effects associated with CFA. These data suggest that phospholipid liposomes containing MTP-PE are superior adjuvants and should receive consideration for vaccine therapy.
authors.affiliation: Department of Immunology, University of Texas M.D. Anderson Cancer Center, Houston 77030.
authors.forename: S E
authors.initials: SE
authors.lastname: Ullrich
authors.forename: I J
authors.initials: IJ
authors.lastname: Fidler
mesh_terms: D000119:Acetylmuramyl-Alanyl-Isoglutamine / Q000031:analogs & derivatives* / Q000276:immunology; D000276:Adjuvants, Immunologic; D000917:Antibody Formation; D000951:Antigens, Neoplasm / Q000276:immunology; D006433:Hemocyanins / Q000276:immunology; D006801:Humans; D006968:Hypersensitivity, Delayed / Q000276:immunology; D007111:Immunity, Cellular; D008081:Liposomes / Q000276:immunology*; D008213:Lymphocyte Activation; D009113:Muramidase / Q000276:immunology; D010714:Phosphatidylethanolamines / Q000276:immunology*
chemical_list: D000276:Adjuvants, Immunologic; D000951:Antigens, Neoplasm; D008081:Liposomes; D010714:Phosphatidylethanolamines; C037144:mifamurtide; D000119:Acetylmuramyl-Alanyl-Isoglutamine; D006433:Hemocyanins; D009113:Muramidase