Cloning of a Tumor Antigen-related Gene in Small Cell Lung Carcinoma.
The Small Cell lung Carcinoma cell line NCI-H128 cDNA library constructed in Lambda gtll was screened by tumor associated antigen specific monoclonal antibody 2F7. The No.4 positive clone was further investigated. The lysogen of the No.4 clone could be induced at 42 degrees to produce 165 kD fusion protein by IPTG. This fusion protein can be detected by both the monoclonal antibody 2F7 and the anti-beta-galactosidase monoclonal antibody. Antigen Competitive Assay showed that the fusion protein purified by PAGE could compete with the natural tumor associated antigen on the membrane and combine with the monoclonal antibody 2F7. PCR reaction showed the inserted DNA fragment of No.4 Clone to be about 1.3 kb. The DNA inserted fragment was sub-cloned into the plasmid vector Bluescript-sk. Northern blot showed that it was specific for H128 cell line. These results showed that the gene of the tumor associated antigen which specifically reacted with the monoclonal antibody 2F7 was cloned.
Cao
Xiao-Bo
XB
Department of Immunology and Cell Biology, Shanghai Cancer Institute, Shanghai 200032, China.
Li
Si-De
SD
Wang
Bing
B
Liu
Jian
J
Mo
Zhong-Geng
ZG
Cao
Xian-Yun
XY