title: Immunological evaluation of peptide vaccination for patients with gastric cancer based on pre-existing cellular response to peptide.
abstract: There is no standard treatment modality for advanced gastric cancer (GC) at the present time. To develop a new treatment modality, we investigated the immunological responses of advanced GC patients (n = 13, 9 non-scirrhous and 4 scirrhous types) vaccinated with peptides to a regimen under which pre-vaccination peripheral blood mononuclear cells (PBMCs) were screened for their reactivity in vitro to each of 14 peptides on HLA-A24 or 16 peptides on -A2 allele, then only the reactive peptides (maximum: 4) were administered in vivo. This regimen was generally well tolerated, although grade I levels of fever and local skin reactions were observed in several patients. Delayed-type hypersensitivity (DTH) to the vaccinated peptides was observed in 4 patients. Increased cellular and humoral immune responses to the vaccinated peptides were observed in post-vaccination PBMCs from 4 of 8 patients and in post-vaccination sera of 8 of 10 patients tested, respectively. Prolonged survival was observed in patients showing cellular and humoral immune responses to the vaccinated peptides in the post-vaccination samples, including all 4 patients with the scirrhous type. These results encourage further development of peptide-based immunotherapy for GC patients.
authors.affiliation: First Department of Surgery, Hokkaido University School of Medicine, N15 W7 Sapporo, Hokkaido 060-8638, Japan.
authors.forename: Yuji
authors.initials: Y
authors.lastname: Sato
authors.forename: Hiroki
authors.initials: H
authors.lastname: Shomura
authors.forename: Yoshiaki
authors.initials: Y
authors.lastname: Maeda
authors.forename: Takashi
authors.initials: T
authors.lastname: Mine
authors.forename: Yoshie
authors.initials: Y
authors.lastname: Une
authors.forename: Yoshinobu
authors.initials: Y
authors.lastname: Akasaka
authors.forename: Masao
authors.initials: M
authors.lastname: Kondo
authors.forename: Shusaku
authors.initials: S
authors.lastname: Takahashi
authors.forename: Toshiki
authors.initials: T
authors.lastname: Shinohara
authors.forename: Kazuko
authors.initials: K
authors.lastname: Katagiri
authors.forename: Mika
authors.initials: M
authors.lastname: Sato
authors.forename: Shiori
authors.initials: S
authors.lastname: Okada
authors.forename: Kanae
authors.initials: K
authors.lastname: Matsui
authors.forename: Akira
authors.initials: A
authors.lastname: Yamada
authors.forename: Hideaki
authors.initials: H
authors.lastname: Yamana
authors.forename: Kyogo
authors.initials: K
authors.lastname: Itoh
authors.forename: Satoru
authors.initials: S
authors.lastname: Todo
mesh_terms: D000230:Adenocarcinoma / Q000276:immunology / Q000517:prevention & control; D000368:Aged; D019496:Cancer Vaccines / Q000627:therapeutic use*; D003602:Cytotoxicity, Immunologic; D005260:Female; D015234:HLA-A Antigens / Q000276:immunology*; D015789:HLA-A2 Antigen / Q000276:immunology*; D059871:HLA-A24 Antigen; D006801:Humans; D007111:Immunity, Cellular; D008207:Lymphatic Metastasis; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000517:prevention & control; D010446:Peptide Fragments / Q000627:therapeutic use*; D012882:Skin Tests; D013274:Stomach Neoplasms / Q000276:immunology / Q000517:prevention & control*; D013602:T-Lymphocytes, Cytotoxic / Q000276:immunology; D016896:Treatment Outcome; D014611:Vaccination
chemical_list: D019496:Cancer Vaccines; D015234:HLA-A Antigens; D015789:HLA-A2 Antigen; D059871:HLA-A24 Antigen; D010446:Peptide Fragments