[Biological activity of human single-chain antibody against amyloid beta peptide involved in Alzheimer's disease].
OBJECTIVE
To explore the biological activity of recombinant human single-chain antibody against amyloid beta peptide in vitro.


METHODS
Human single-chain antibody against amyloid beta peptide was obtained from recombinant bacteria. The antigen-binding activity of this antibody was measured by enzyme-linked immunosorbent assay (ELISA) and competitive ELISA. Human neuroblastoma SH-SY5Y cells were used as cell models to test the protective role of human single-chain antibody against amyloid beta peptide.


RESULTS
Recombinant human single-chain antibody was mainly located in the insoluble inclusion bodies of bacteria. The antibody was dissolved by urea and purified by metal affinity chromatography as active form to bind synthetic amyloid beta peptide 40 or amyloid beta peptide 42. The improvement of the survival rates of human neuroblastoma cells was significantly superior in amyloid peptide 42 plus equimolar antibody group than in amyloid peptide 42 group (P < 0.05), and was significantly superior in the amyloid peptide 40 plus equimolar antibody group than in amyloid peptide 40 group (P < 0.01).


CONCLUSIONS
The recombinant human single-chain antibody against beta amyloid peptide 40 from E. coli can partially inhibit the neurotoxicity effect of amyloid beta peptide in vitro.
Department of Nuclear Medicine, PUMC Hospital, PUMC and CAMS, Beijing 100730, China. jiongcai@sina.com
Jiong
J
Cai
Fang
F
Li
Fei
F
Liu
Shi-zhen
SZ
Wang
D016229:Amyloid beta-Peptides / Q000276:immunology* / Q000378:metabolism / Q000633:toxicity; D045744:Cell Line, Tumor; D002470:Cell Survival / Q000187:drug effects; D006801:Humans; D010446:Peptide Fragments / Q000378:metabolism / Q000633:toxicity; D011485:Protein Binding; D011994:Recombinant Proteins / Q000494:pharmacology; D057127:Single-Chain Antibodies / Q000494:pharmacology*
D016229:Amyloid beta-Peptides; D010446:Peptide Fragments; D011994:Recombinant Proteins; D057127:Single-Chain Antibodies; C078592:amyloid beta-protein (1-40); C075222:amyloid beta-protein (1-42)