In vitro and in silico approaches to obtain tailored reagents - Nanobodies as a model

Antibodies possess unattainable capacity to bind selectively and at high affinity their cognates. For this reason they have been largely used in applications which rely on specific molecular recognition. Biosensors, nanoparticles, and even cells can be functionalized with antibodies for improving sensitivity and target specificity whereas both basic research and diagnostics require those reagents for localizing and quantifying biomarkers. However, conventional antibodies (IgGs) are large molecules (150 kDa) that are difficult to engineer and expensive to produce. In the last years, several scaffolds and antibody fragments have become more and more popular as effective alternatives to IgGs and specifically nanobodies raised enthusiasm because of their minimal mass (14 kDa), high stability and relative similarity to human sequences. Finally, their short sequence enables relatively fast optimization of their biophysical features by exploiting computational resources. This seminar will describe the general features of nanobodies, the suitable selection, production, and engineering methodologies and will illustrate some specific application examples of these reagents.