title: A HER-2/neu peptide admixed with PLA microspheres induces a Th1-biased immune response in mice.
abstract: The elimination of cancer cells requires strong cellular immune responses, and these responses are induced by the activation of Th1 lymphocytes. In this work, the possibility of inducing a Th1 type of immune response in vivo by mixing a HER-2/neu synthetic CTL (cytotoxic T lymphocyte) peptide [HER-2/neu (789-797)], with poly-lactide (PLA) microspheres was investigated. Various formulations of the peptide were administered to HLA-A2.1 transgenic (HHD) mice. Cellular experiments, assessing proliferation and cytokine determination in splenocyte culture supernatants, were carried out in order to evaluate the type of immune response to the antigen. The in vivo administration of the peptide antigen admixed with the PLA microspheres induced a potent immune response which was comparable to that induced by the combination of the antigen in complete Freund's adjuvant (CFA). Furthermore, the cytokine profile produced by the T lymphocytes of the immunized animals indicated that the combination of the peptide antigen with the PLA microspheres induced a strong Th1 biased immune response to the antigen. The time of peptide incubation with the microspheres prior to administration did not affect the immune response, which further simplifies the preparation of this type of vaccine. The results justify further investigation of the possibility of inducing effective cellular immune responses against cancer cells overexpressing HER-2/neu molecules by simply mixing appropriate HER-2/neu peptide antigens with PLA microspheres.
authors.affiliation: Mass Spectrometry and Dioxin Analysis Laboratory, IRRP, National Centre for Scientific Research "Demokritos", 15310 Athens, Greece.
authors.forename: Konstantina N
authors.initials: KN
authors.lastname: Nikou
authors.forename: Nikolaos
authors.initials: N
authors.lastname: Stivaktakis
authors.forename: Konstantinos
authors.initials: K
authors.lastname: Avgoustakis
authors.forename: Panagiota A
authors.initials: PA
authors.lastname: Sotiropoulou
authors.forename: Sonia A
authors.initials: SA
authors.lastname: Perez
authors.forename: Constantin N
authors.initials: CN
authors.lastname: Baxevanis
authors.forename: Michael
authors.initials: M
authors.lastname: Papamichail
authors.forename: Leondios
authors.initials: L
authors.lastname: Leondiadis
mesh_terms: D000818:Animals; D020099:Coated Materials, Biocompatible / Q000008:administration & dosage / Q000737:chemistry; D004058:Diffusion; D004337:Drug Carriers / Q000008:administration & dosage / Q000737:chemistry*; D000939:Epitopes / Q000276:immunology; D007114:Immunization / Q000379:methods; D008422:Materials Testing; D051379:Mice; D008863:Microspheres; D010446:Peptide Fragments / Q000008:administration & dosage / Q000737:chemistry / Q000276:immunology; D011091:Polyesters / Q000737:chemistry*; D011485:Protein Binding; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000008:administration & dosage* / Q000737:chemistry / Q000276:immunology*; D018417:Th1 Cells / Q000187:drug effects* / Q000276:immunology*; D014612:Vaccines / Q000276:immunology* / Q000627:therapeutic use
chemical_list: D020099:Coated Materials, Biocompatible; D004337:Drug Carriers; D000939:Epitopes; D010446:Peptide Fragments; D011091:Polyesters; D018719:Erb-b2 Receptor Tyrosine Kinases; D014612:Vaccines; C033616:poly(lactide)