Liposomal formulation of a self lymphoma antigen induces potent protective antitumor immunity.
We developed a liposome carrier for a model nonimmunogenic, self Ag. This carrier reproducibly converted lymphoma Ig into a potent tumor rejection Ag in mice. A single immunization induced protection against challenges representing 20 to 100 times the minimum lethal dose of parental tumor. This protective effect required minimal amounts of incorporated Ag and IL-2 and elicited specific Abs (compared with free Ag or liposomal control Ig which did not elicit any specific Abs); depletion experiments demonstrated a requirement for effector CD4+ and CD8+ T cells. Head-to-head comparisons, indicating superior potency and induction of specific T cell activation, distinguished liposomal from prototype, carrier-conjugated Ag. These results provide a strategy for formulating weak tumor or other clinically important Ags into vaccines.
Kwak
L W
LW
Department of Experimental Transplantation and Immunology, Medicine Branch, Division of Clinical Sciences, National Cancer Institute, Bethesda, MD 20892, USA. kwak@ncifcrf.gov
Pennington
R
R
Boni
L
L
Ochoa
A C
AC
Robb
R J
RJ
Popescu
M C
MC
D000818:Animals; D000951:Antigens, Neoplasm / Q000008:administration & dosage*; D019496:Cancer Vaccines / Q000008:administration & dosage; D005260:Female; D007114:Immunization; D007130:Immunoglobulin Idiotypes / Q000008:administration & dosage; D066298:In Vitro Techniques; D007376:Interleukin-2 / Q000008:administration & dosage; D007519:Isoantigens / Q000008:administration & dosage; D008081:Liposomes; D008213:Lymphocyte Activation; D008212:Lymphocyte Depletion; D008223:Lymphoma / Q000276:immunology* / Q000628:therapy*; D051379:Mice; D008809:Mice, Inbred C3H; D009368:Neoplasm Transplantation; D013601:T-Lymphocytes / Q000276:immunology; D014185:Transplantation, Isogeneic
D000951:Antigens, Neoplasm; D019496:Cancer Vaccines; D007130:Immunoglobulin Idiotypes; D007376:Interleukin-2; D007519:Isoantigens; D008081:Liposomes