Immunological evaluation of vaccination with pre-designated peptides frequently selected as vaccine candidates in an individualized peptide vaccination regimen.
We previously conducted a trial of an 'individualized' regimen, in which cancer patients were vaccinated with peptides after the confirmation of pre-existing peptide-specific cytotoxic T lymphocyte (CTL) precursors. In this study, we performed a new trial of 'pre-designated' regimen, in which cancer patients were vaccinated with peptides that were frequently selected as vaccine candidates in the preceding individualized regimen. Eighteen cancer patients (10 with uterine cervical cancer and 8 with gastric cancer) were enrolled in the new regimen. The pre-designated regimen was well tolerated by all patients. Although peptide-specific CTL precursors and humoral responses increased in the majority of patients with the pre-designated regimen, neither of the responses correlated with clinical outcome. Three patients had long stable disease, and their pre-vaccination peripheral blood mononuclear cells contained peptide-specific CTL precursors reactive to more than 2 of 4 peptides. With the pre-designated regimen, the levels of pre-existing immunoglobulin G reactive to non-vaccinated peptides decreased in 5 of 15 patients with progressive disease, and their time to progression was very short, whereas such a decrease was rarely observed in the preceding individualized regimen. These results suggest that the pre-designated regimen can elicit a primary immune response, but may incidentally suppress pre-existing immune responses.
Mochizuki
Kazuo
K
Department of Gynecology, Kurume University, School of Medicine, Fukuoka 830-0011, Japan.
Sato
Yuji
Y
Tsuda
Naotake
N
Shomura
Hiroki
H
Sakamoto
Masaru
M
Matsuura
Kimio
K
Ushijima
Kimio
K
Maeda
Yoshiaki
Y
Katagiri
Kazuko
K
Yamada
Akira
A
Todo
Satoru
S
Kamura
Toshiharu
T
Harada
Mamoru
M
Itoh
Kyogo
K
D000328:Adult; D000368:Aged; D000917:Antibody Formation; D019496:Cancer Vaccines; D005260:Female; D006801:Humans; D006968:Hypersensitivity, Delayed; D007111:Immunity, Cellular; D008297:Male; D008875:Middle Aged; D010446:Peptide Fragments / Q000276:immunology / Q000627:therapeutic use; D013602:T-Lymphocytes, Cytotoxic / Q000276:immunology; D002583:Uterine Cervical Neoplasms / Q000276:immunology*
D019496:Cancer Vaccines; D010446:Peptide Fragments