<p><b>OBJECTIVE</b>To explore the
biological activity of recombinant
human single-chain antibody against
amyloid beta peptide in vitro.</p><p><b>
METHODS</b>
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.</p><p><b>RESULTS</b>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).</p><p><b>CONCLUSION</b>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.</p>