Article

Generation of a monoclonal human single chain antibody fragment to hepatic stellate cells--a potential mechanism for targeting liver anti-fibrotic therapeutics.

School of Medical Sciences, Institute of Medical Sciences, University of Aberdeen, Foresterhill, Aberdeen AB25 2ZD, UK.
Journal of Hepatology (impact factor: 9.26). 07/2005; 42(6):888-96. DOI:10.1016/j.jhep.2005.01.028 pp.888-96
Source: PubMed

ABSTRACT Hepatic stellate cells are pivotal to fibrogenesis in the liver and many potential anti-fibrotic therapeutics are required to act on targets within hepatic stellate cells. The aim of this study was to generate a human antibody fragment to hepatic stellate cells.
Phage display was used to generate a human monoclonal antibody fragment to a peptide sequence present on an extracellular domain of synaptophysin, a protein expressed on the surface of hepatic stellate cells.
An antibody fragment was isolated (termed C1-3), expressed in bacteria and purified. Fluorescently-labelled C1-3 antibody associated with human hepatic stellate cells but not hepatocytes in culture. Binding of fluorescently labelled C1-3 to hepatic stellate cells was blocked by the extracellular synaptophysin peptide sequence and uptake of the antibody intracellularly was inhibited by monensin. The toxin tributyl tin-when conjugated to C1-3-retained the ability to kill hepatic stellate cells confirming that C1-3 is sequestered intracellularly.
This antibody fragment may be an effective means to target therapeutics to human hepatic stellate cells.

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Keywords

antibody fragment
 
antibody intracellularly
 
bacteria
 
C1-3-retained
 
extracellular synaptophysin peptide sequence
 
fluorescently labelled C1-3
 
Fluorescently-labelled C1-3 antibody
 
Hepatic stellate cells
 
hepatocytes
 
human antibody fragment
 
human hepatic stellate cells
 
human monoclonal antibody fragment
 
peptide sequence present
 
potential anti-fibrotic therapeutics
 
synaptophysin
 
toxin tributyl tin-when conjugated
 
uptake