title: Identification of tumor associated antigens recognized by IgG from tumor-infiltrating B cells of lung cancer: correlation between Ab titer of the patient's sera and the clinical course.
abstract: We previously demonstrated that TIB recognize tumor antigens and produce antibodies against them. In the present study, we identified three tumor antigens recognized by TIB in lung cancer and evaluated whether changes in the antibody titer against these antigens correlated with the patient's clinical course. A lung cancer cell line, G603L, was established from a primary lung tumor of a patient, G603. Seven months later, adrenal metastasis was detected and surgically resected. The latter tumor was mildly infiltrated with B cells and xenotransplanted into SCID mice to obtain human IgG. A cDNA library was constructed from G603L and SEREX was carried out using TIB-derived IgG. The sero-reactive clones were sequenced and one of these antigens was revealed to be MAGE-B2 whereas the others were novel antigens. In the immuno-monitoring of the patient's sera, high antibody titer against MAGE-B2 was observed before operation and the titer decreased after resection of the primary tumor. It was elevated again at the time of adrenal metastasis, but then decreased after resection. The change in antibody titer against the second antigen was similar to MAGE-B2, and the antibody titer against the third antigen was low before the primary operation but increased at the time of recurrence. Our results suggest that TIB recognized tumor antigens and the antibody titers against these antigens were changed along with the patient's clinical course. Therefore, these antibodies could be used as tumor markers for the patient.
authors.affiliation: Department of Surgery II, School of Medicine, University of Occupational and Environmental Health, Iseigaoka 1-1, Yahatanishi-ku, Kitakyushu 807-8555, Japan. macky@med.uoeh-u.ac.jp
authors.forename: Makiko
authors.initials: M
authors.lastname: Mizukami
authors.forename: Takeshi
authors.initials: T
authors.lastname: Hanagiri
authors.forename: Tetsuro
authors.initials: T
authors.lastname: Baba
authors.forename: Takashi
authors.initials: T
authors.lastname: Fukuyama
authors.forename: Yoshika
authors.initials: Y
authors.lastname: Nagata
authors.forename: Tetsuya
authors.initials: T
authors.lastname: So
authors.forename: Yoshinobu
authors.initials: Y
authors.lastname: Ichiki
authors.forename: Masakazu
authors.initials: M
authors.lastname: Sugaya
authors.forename: Manabu
authors.initials: M
authors.lastname: Yasuda
authors.forename: Mitsuhiro
authors.initials: M
authors.lastname: Takenoyama
authors.forename: Kenji
authors.initials: K
authors.lastname: Sugio
authors.forename: Kosei
authors.initials: K
authors.lastname: Yasumoto
mesh_terms: D000368:Aged; D000818:Animals; D000912:Antibodies, Neoplasm / Q000097:blood; D000951:Antigens, Neoplasm / Q000276:immunology*; D001402:B-Lymphocytes / Q000276:immunology*; D001483:Base Sequence; D045744:Cell Line, Tumor; D017931:DNA Primers; D018450:Disease Progression; D005260:Female; D015723:Gene Library; D006801:Humans; D007074:Immunoglobulin G / Q000276:immunology*; D008175:Lung Neoplasms / Q000097:blood / Q000235:genetics / Q000276:immunology*; D008297:Male; D051379:Mice; D016513:Mice, SCID; D012333:RNA, Messenger / Q000032:analysis / Q000235:genetics; D014183:Transplantation, Heterologous
chemical_list: D000912:Antibodies, Neoplasm; D000951:Antigens, Neoplasm; D017931:DNA Primers; D007074:Immunoglobulin G; D012333:RNA, Messenger