[Screening and characterization of human phage Fab antibody gene to prostate specific membrane antigen].
OBJECTIVE
To screen and characterize the variable region gene about prostate specific membrane antigen (PSMA) of the Chinese Fab fragment, and to establish a new approach to researches on PSMA and prostate gene therapy.


METHODS
We used purified PSMA protein as antigen, stuck it on the ELISA plate and scanned the phage Fab fragment antibody library by phage display technology. After five cycles of "absorbing-elution-amplification", we got the Fab fragment phage antibody of PSMA with high antigen binding ability and specificity, and tested it with immunodetection and sequencing.


RESULTS
The sequence of Fd fragment was 696 base pairs encoding 232 amino-acid residues, with 98% homological similarity to the human immunoglobulin gamma chain, while the light chain was constructed by 630 base pairs encoding 210 amino-acid residues, with 93% homological similarity to kappa chain.


CONCLUSIONS
Using phage display technology, we obtained the gene sequence of Fab antibody fragment specific to PSMA, and the antibody gene has the classic structural features of immunoglobulin light chain and heavy chain. The coding output of the antibody gene has the specificity and immunological competence to PSMA.
Huang
Hai
H
Department of Urology, Second Affiliated Hospital of Sun Yat-sen University, Guangzhou, Guangdong 510120, China. huanghai257@126.com
Huang
Jian
J
Lin
Tian-Xin
TX
Xu
Ke-Wei
KW
Guo
Zheng-Hui
ZH
Jiang
Chun
C
Han
Jin-Li
JL
D003001:Cloning, Molecular; D004797:Enzyme-Linked Immunosorbent Assay; D005815:Genetic Code; D006801:Humans; D007140:Immunoglobulin Fab Fragments / Q000235:genetics*; D007135:Immunoglobulin Variable Region / Q000235:genetics*; D008297:Male; D019151:Peptide Library; D017430:Prostate-Specific Antigen / Q000276:immunology*
D007140:Immunoglobulin Fab Fragments; D007135:Immunoglobulin Variable Region; D019151:Peptide Library; D017430:Prostate-Specific Antigen