Advantages of IgY
Deckers S, Braren I, Greunke K, Meyer N, Rühl D, Bredehorst R, Spillner E., Biotechnol Appl Biochem. 2008 Jul 3. [Epub ahead of print] Nowadays, recombinant antibody and phage display technology enable the efficient generation of immunotools and a subsequent manipulation for optimized affinity, specificity or overall performance. Such advantages are of particular interest for haptenic target structures one of which is 2,4,6-trinitrotoluene (TNT). The toxicity of TNT and its breakdown products makes a reliable and fast detection of low levels in aqueous samples highly important. In this study we aimed for the generation of single chain antibody fragments (scFv) specific for the TNT-surrogate 2,4,6-trinitrophenyl (TNP) and their subsequent production as monoclonal avian IgY immunoglobulins providing improved assay performance. Therefore, we subjected a human synthetic scFv library to selection following different strategies. TNP-specific human antibody fragments could be identified, characterised for their primary structure and evaluated for production as soluble scFv in E. coli. Additionally, a murine TNP-specific antibody fragment was obtained from the hybridoma 11B3, however, the procaryotic expression level was found to be limited. To generate and evaluate immunoglobulin formats with superior characteristics, all recombinant antibody fragments then were converted into two different chimeric bivalent IgY antibody formats. After expression in mammalian cells, the IgY antibodies were assessed for their reactivity towards TNT. The IgY antibodies generated on the basis of the combinatorial library proved to be useful for detection of TNT, thereby emphasizing the high potential of this approach for the development of detection devices for immunoassay-based techniques.
