Immunoscreening of a cDNA library from a lung cancer cell line using autologous patient serum: Identification of XAGE-1b as a dominant antigen and its immunogenicity in lung adenocarcinoma.
By serologic identification of antigens by recombinant expression cloning (SEREX) analysis using an autologous lung adenocarcinoma cell line, OU-LU-6, as a cDNA library source, we demonstrated that XAGE-1 was the dominant antigen recognized by serum from a patient. By immunoscreening, we obtained 38 positive cDNA clones consisting of 16 genes designated as OY-LC-1 to -OY-LC-16. OY-LC-1, represented by 18 clones, was identical to XAGE-1. OY-LC-2 to -16, represented by either a single or 2 clones, were identical to known genes shown to be ubiquitously expressed in various normal tissues. RT-PCR analysis showed that of 4 XAGE-1 transcripts-XAGE-1a, b, c and d-XAGE-1b was expressed in OU-LU-6 dominantly. Furthermore, XAGE-1b mRNA was expressed in 4 of 10 lung cancer tissues, whereas no expression was observed in normal tissues. Of 4 XAGE-1b mRNA positive cancer tissues, 3 were adenocarcinoma and one was poorly differentiated squamous cell carcinoma. Of 32 sera from lung cancer patients, 8 sera were reactive with the XAGE-1b product. Those 8 sera were from patients with adenocarcinoma. These findings indicated strong immunogenicity of XAGE-1b in lung adenocarcinoma and suggested its potential use as a target for vaccine-based immunotherapies.
Ali Eldib
Ali Mohamed
AM
Department of Immunology, Okayama University Graduate School of Medicine and Dentistry, Okayama, Japan.
Ono
Toshiro
T
Shimono
Michihide
M
Kaneko
Miho
M
Nakagawa
Kazuhiko
K
Tanaka
Ryo
R
Noguchi
Yuji
Y
Nakayama
Eiichi
E
D000230:Adenocarcinoma / Q000097:blood* / Q000235:genetics / Q000276:immunology; D000328:Adult; D017398:Alternative Splicing; D000951:Antigens, Neoplasm / Q000235:genetics* / Q000276:immunology*; D003001:Cloning, Molecular; D015972:Gene Expression Regulation, Neoplastic; D015723:Gene Library; D006801:Humans; D016056:Immunodominant Epitopes / Q000276:immunology*; D008175:Lung Neoplasms / Q000097:blood* / Q000235:genetics / Q000276:immunology; D008297:Male; D020033:Protein Isoforms; D012333:RNA, Messenger / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D017422:Sequence Analysis, DNA; D014407:Tumor Cells, Cultured
D000951:Antigens, Neoplasm; D016056:Immunodominant Epitopes; D020033:Protein Isoforms; D012333:RNA, Messenger; C413656:XAGE1A protein, human