title: Preparation and characterization of anti-tissue factor single-chain variable fragment antibody for cancer diagnosis.
abstract: Tissue factor (TF), which serves as the initiator of the extrinsic blood coagulation cascade, has been found to be overexpressed in various solid tumors, especially brain tumors, pancreatic cancer, and gastric cancer. Overexpression of TF is considered to contribute to the high incidence of thrombotic complications and poor prognosis in patients with such cancers. Therefore, detection or targeting of TF may be a promising approach for the diagnosis and treatment of solid tumors that are known to overexpress the protein. Here, we used the recombinant DNA technology to develop an anti-TF single-chain Fv (scFv) of small size and high affinity for its target. The biochemical characteristics of the anti-TF scFv were evaluated using surface plasmon resonance (SPR) sensing and flow cytometry. The data obtained showed that the affinity of the anti-TF scFv was 2.04 × 10(-8) (KD), and that the protein showed significant binding to the cancer cells. Then, Alexa 647-labeled anti-TF scFv and anti-TF IgG were administered to mice bearing chemically induced spontaneous tumors. The maximum tumor to background ratios of anti-TF scFv and anti-TF IgG were obtained 3 and 24 h after the injections, respectively. This study indicates anti-TF scFv may be suitable as an imaging probe for the diagnosis of solid tumors.
authors.affiliation: Division of Developmental Therapeutics, Research Center for Innovative Oncology, National Cancer Center Hospital East, Chiba, Japan; Laboratory of Cancer Biology, Department of Integrated Biosciences, Graduate School of Frontier Sciences, The University of Tokyo, Chiba, Japan.
authors.forename: Ryuta
authors.initials: R
authors.lastname: Sato
authors.forename: Toshifumi
authors.initials: T
authors.lastname: Obonai
authors.forename: Ryo
authors.initials: R
authors.lastname: Tsumura
authors.forename: Kouhei
authors.initials: K
authors.lastname: Tsumoto
authors.forename: Yoshikatsu
authors.initials: Y
authors.lastname: Koga
authors.forename: Masahiro
authors.initials: M
authors.lastname: Yasunaga
authors.forename: Yasuhiro
authors.initials: Y
authors.lastname: Matsumura
mesh_terms: D000818:Animals; D045744:Cell Line, Tumor; D005260:Female; D006801:Humans; D051379:Mice; D009374:Neoplasms, Experimental; D010190:Pancreatic Neoplasms / Q000175:diagnosis*; D057127:Single-Chain Antibodies; D012878:Skin Neoplasms / Q000175:diagnosis*; D020349:Surface Plasmon Resonance; D013925:Thromboplastin / Q000378:metabolism*
chemical_list: D057127:Single-Chain Antibodies; D013925:Thromboplastin
keywords: Cancer diagnosis; molecular imaging; monoclonal antibody; single-chain variable fragment; tissue factor