title: Analysis of naïve and memory CD4 and CD8 T cell populations in breast cancer patients receiving a HER2/neu peptide (E75) and GM-CSF vaccine.
abstract: We are conducting clinical trials of the E75 peptide as a vaccine in breast cancer (BrCa) patients. We assessed T cell subpopulations in BrCa patients before and after E75 vaccination and compared them to healthy controls. We obtained 17 samples of blood from ten healthy individuals and samples from 22 BrCa patients prior to vaccination. We also obtained pre- and post-vaccination samples of blood from seven BrCa patients who received the E75/GM-CSF vaccine. CD4, CD8, CD45RA, CD45RO, and CCR7 antibodies were used to analyze the CD4+ and CD8+ T cells by four-color flow cytometry. Compared to healthy individuals, BrCa patients have significantly more memory and less naïve T cells and more effector-memory CD8+ and less effector CD4+ T cells. Phenotypic differences in defined circulating CD4+ and CD8+ T cell subpopulations suggest remnants of an active immune response to tumor distinguished by a predominant memory T cell response and by untapped recruitment of naïve helper and cytotoxic T cells. E75 vaccination induced recruitment of both CD4+ and CD8+ naïve T cells while memory response remained stable. Additionally, vaccination induced global activation of all T cells, with specific enhancement of effector CD4+ T cells. E75 vaccination causes activation of both memory and naïve CD4+ and CD8+ T cells, while recruiting additional naïve CD4+ and CD8+ T cells to the overall immune response.
authors.affiliation: Clinical Breast Care Project, Department of Surgery, Walter Reed Army Medical Center, Washington, DC 20307, USA.
authors.forename: Matthew T
authors.initials: MT
authors.lastname: Hueman
authors.forename: Alexander
authors.initials: A
authors.lastname: Stojadinovic
authors.forename: Catherine E
authors.initials: CE
authors.lastname: Storrer
authors.forename: Zia A
authors.initials: ZA
authors.lastname: Dehqanzada
authors.forename: Jennifer M
authors.initials: JM
authors.lastname: Gurney
authors.forename: Craig D
authors.initials: CD
authors.lastname: Shriver
authors.forename: Sathibalan
authors.initials: S
authors.lastname: Ponniah
authors.forename: George E
authors.initials: GE
authors.lastname: Peoples
mesh_terms: D015703:Antigens, CD / Q000276:immunology; D001943:Breast Neoplasms / Q000276:immunology* / Q000628:therapy; D015496:CD4-Positive T-Lymphocytes / Q000187:drug effects / Q000276:immunology*; D018414:CD8-Positive T-Lymphocytes / Q000187:drug effects / Q000276:immunology*; D019496:Cancer Vaccines / Q000276:immunology* / Q000627:therapeutic use; D005260:Female; D005434:Flow Cytometry; D005455:Fluorescent Antibody Technique; D016178:Granulocyte-Macrophage Colony-Stimulating Factor / Q000276:immunology* / Q000627:therapeutic use; D006801:Humans; D007156:Immunologic Memory; D016130:Immunophenotyping; D008213:Lymphocyte Activation; D010446:Peptide Fragments / Q000276:immunology* / Q000627:therapeutic use
chemical_list: D015703:Antigens, CD; D019496:Cancer Vaccines; C474513:HER-2 peptide E75 (369-377), human; D010446:Peptide Fragments; D016178:Granulocyte-Macrophage Colony-Stimulating Factor