Selection and Evaluation of Specific Single Chain Antibodies against CD90, a Marker for Mesenchymal and Cancer Stem Cells

Background: CD90, a membrane-associated glycoprotein is a marker used to identify mesenchymal stem cells (MSCs). Recent studies have introduced CD90, which induces tumorigenic activity, as a cancer stem cell (CSC) marker in various malignancies. Blocking CD90 activity with anti-CD90 monoclonal antibodies enhanced anti-tumor effects. To date, highly specific antibody single-chain variable fragments (scFvs) have been isolated against various targets and showed promising results in cancer immunotherapy.