Development of sugar chain-binding single-chain variable fragment antibody to adult T-cell leukemia cells using glyco-nanotechnology and phage display method

Abstract

Adult T-cell leukemia (ATL) is an intractable blood cancer caused by the infection of human T-cell leukemia virus type-1, and effective medical treatment is required. It is known that the structure and expression levels of cell surface sugar chains vary depending on cell states such as inflammation and cancer. Thus, it is expected that the antibody specific for ATL cell surface sugar chain would be an effective diagnostic tool and a strong candidate for the development of an anti-ATL drug. Here, we developed a stable sugar chain-binding single-chain variable fragment antibody (scFv) that can bind to ATL cells using a fibre-type Sugar Chip and phage display method. The fiber-type Sugar Chips were prepared using O-glycans released from ATL cell lines. The scFv-displaying phages derived from human B cells (diversity: 1.04 × 108) were then screened using the fiber-type Sugar Chips, and an O-glycan-binding scFv was obtained. The flow cytometry analysis revealed that the scFv predominantly bound to ATL cell lines. The sugar chain-binding properties of the scFv was evaluated by array-type Sugar Chip immobilized with a library of synthetic glycosaminoglycan disaccharide structures. Highly sulphated disaccharide structures were found to have high affinity to scFv.

Clinical implications of phage display technique: Digging deeper in diagnostic and therapeutic grounds.

“…Adult T-cell leukemia (ALT), caused by T-cell leukemia virus type I, expresses sugar chain that are likely to be specific for the diseased state. Using fiber-type Sugar Chip (fiSC) that could enables the interaction of sugar binding proteins with sugar chains, Muchima, et al [54] screened scFv fragments that could bind to ALT cell surface sugar chain, O-glycan, illustrated in figure. The study reported the extraction of two highly sulfated disaccharide structures having high affinity for ALT where, non-ALT cells were used as the control.…”