ScFv is your new research option

As the development of engineered antibody, scFv (single-chain fragment variable) has attracted more and more attention in research of theoretical and practical applications. Compared to antibody, scFv is characteristic of small molecular weight, which accounted for 1/6 of MW of whole antibody. It is considered to be as the smallest functional unit with antibody biological activity.

ScFv is a small engineered antibody in which the variable heavy chain(VH) and light chain (VL) of the antibody are connected by a short polypeptide linker with 15-20 amino acids. No Fc chain is included. ScFv was first found and expressed successfully in yeasts and plant cells, and it was able to spontaneously fold to form a natural structure with antigen-binding properties. There are great application prospects of scFv in the antiviral, tumor cell therapy, autoimmune diseases therapy, targeted drug therapy and so on.

ScFv antibodies have lots of characteristics, including antigen-binding, strong penetrability, short half-life in vivo, low immunogenicity, expression in prokaryotic expression system and easy genetic engineering operation, etc., and the research on it is very hot. Phage display technology has been widely used to prepare scFv, and the process includes the following aspects:

1. Cloning and recombination of antibody gene. The variable heavy chain and light chain of the antibody gene is amplified by PCR with specific degenerate primers, and then the two chains are connected by a short polypeptide linker to form the full scFv.

2. Construction and expression of antibody gene expression vector. The successfully amplified scFv gene was transferred into the phagemid vector and transformed into host cells to construct a phage single-chain antibody library.

3.Enrichment of phage single-chain antibody library and screening. Usually a library of 109 phage-displayed scFv molecules was obtained through several rounds of adsorption, washing, elution and amplification processed. Each phage could represent a scFv antibody.

4.Soluble expression of scFv. In the construction of expressed vector of scFv, several tags at C-terminus of scFv antibody could contribute to the detection and purification of expression products, such as c-Myc, histidine, GST, MBP, lipid label and so on.

Cloud-Clone Corp. has developed the platform for scFv antibody preparation after years of effort (shown below).

Cloud-Clone Corp. has broken the species limits of the traditional monoclonal antibody preparation technology to provide the more efficient and cheaper monoclonal antibody preparation services to researchers and industrial customers. 

For more products, please visit: www.cloud-clone.com.