title: Virus-like particles induce robust human T-helper cell responses.
abstract: Among synthetic vaccines, virus-like particles (VLPs) are used for their ability to induce strong humoral responses. Very little is reported on VLP-based-vaccine-induced CD4(+)  T-cell responses, despite the requirement of helper T cells for antibody isotype switching. Further knowledge on helper T cells is also needed for optimization of CD8(+)  T-cell vaccination. Here, we analysed human CD4(+)  T-cell responses to vaccination with MelQbG10, which is a Qβ-VLP covalently linked to a long peptide derived from the melanoma self-antigen Melan-A. In all analysed patients, we found strong antibody responses of mainly IgG1 and IgG3 isotypes, and concomitant Th1-biased CD4(+)  T-cell responses specific for Qβ. Although less strong, comparable B- and CD4(+)  T-cell responses were also found specific for the Melan-A cargo peptide. Further optimization is required to shift the response more towards the cargo peptide. Nevertheless, the data demonstrate the high potential of VLPs for inducing humoral and cellular immune responses by mounting powerful CD4(+)  T-cell help.
authors: Ludwig Center for Cancer Research of University of Lausanne, Switzerland.
authors: Marion
authors: M
authors: Braun
authors: Camilla
authors: C
authors: Jandus
authors: Patrik
authors: P
authors: Maurer
authors: Anya
authors: A
authors: Hammann-Haenni
authors: Katrin
authors: K
authors: Schwarz
authors: Martin F
authors: MF
authors: Bachmann
authors: Daniel E
authors: DE
authors: Speiser
authors: Pedro
authors: P
authors: Romero
mesh_terms: D000328:Adult; D000368:Aged; D000917:Antibody Formation; D015704:CD4 Antigens / Q000378:metabolism; D019496:Cancer Vaccines; D002478:Cells, Cultured; D005260:Female; D006801:Humans; D058965:MART-1 Antigen / Q000276:immunology*; D008297:Male; D008545:Melanoma / Q000276:immunology*; D008875:Middle Aged; D009367:Neoplasm Staging; D010446:Peptide Fragments; D012878:Skin Neoplasms / Q000276:immunology*; D006377:T-Lymphocytes, Helper-Inducer / Q000378:metabolism* / Q000473:pathology; D014771:Virion / Q000276:immunology*
chemical_list: D015704:CD4 Antigens; D019496:Cancer Vaccines; D058965:MART-1 Antigen; C548667:MLANA protein, human; D010446:Peptide Fragments