The application of single-chain Fv fragments (scFv) in medicine and biotechnology places great demands on their stability. Only recently has attention been given to the production of highly stable scFvs, and in a number of examples it was found that such fragments indeed perform better during practical applications. The structural parameters influencing scFv stability are now beginning to be el...

Sandwich enzyme-linked immunosorbent assay (ELISA) microarrays can simultaneously quantify the levels of multiple diagnostic targets in a biological sample. However, as with traditional ELISA diagnostics, endogenous antibodies in patient sera can cause interference. We demonstrate here that reducing the diagnostic capture antibody to its minimal functional unit (i.e., a single-chain antibody fr...

Complementarity determining region (CDR) transplant studies were conducted between two monoclonal antibodies of distinctly different specificities (anti-fluorescein monoclonal antibody (mAb) 4-4-20 and anti-single-stranded DNA (ssDNA) mAb 04-01) which possessed nearly identical light chains but dissimilar heavy chains. The variations in binding specificities between the two immunoglobulins sugg...

BACKGROUND Due to their unique ability to bind their targets with high fidelity, antibodies are used widely not only in biomedical research, but also in many clinical applications. Recombinant antibodies, including single chain variable fragments (scFv), are gaining momentum because they allow powerful in vitro selection and manipulation without loss of function. Regardless of the ultimate appl...

Genetic engineering has resulted in more than 50 recombinant bispecific antibody formats over the past two decades. Bispecific scFv antibodies represent a successful and promising immunotherapy platform that retargets cytotoxic T cells to tumor cells, with one scFv directed to tumor-associated antigens and the other to T cells. Based on this antibody construct, strategies for both specific tumo...

We report a microcantilever-based immunosensor operated in static deflection mode with a performance comparable with surface plasmon resonance, using single-chain Fv (scFv) antibody fragments as receptor molecules. As a model system scFv fragments with specificity to two different antigens were applied. We introduced a cysteine residue at the C terminus of each scFv construct to allow covalent ...

Quiescent Escherichia coli cells are generated by overexpressing the Rcd transcript in an hns-205 mutant host. The resulting nongrowing, metabolically active cells were used here to express a single-chain antibody fragment (scFv) in shake flask and fermentor cultures. The expression system is based on two plasmids; one carries the product gene expressed from lambdaP(L) under the control of the ...

Screening randomly mutagenized proteins displayed on a phage surface by biopanning is a powerful strategy to obtain evolved clones with improved properties such as higher stability and functionality. We utilized this method to overcome the problem that functional single-chain antibodies against active gibberellins, a class of plant hormones, can not be prepared by some of the conventional metho...

Construction of a bispecific single-chain antibody derivative is described that consists of two different single-chain Fv fragments joined through a Gly-Ser linker. One specificity of the two Fv fragments is directed against the CD3 antigen of human T cells and the other is directed against the epithelial 17-1A antigen; the latter had been found in a clinical trial to be a suitable target for a...