As is the case with single biological molecules discussed in Chapter 13, optical tweezers have also played a significant role in advancing our understanding of complex cellular processes. To this end, mechanical interactions between cells, or between cells and their environment, have been probed using optical tweezers as force transducers, utilising their capability as a powerful tool to probe forces that are relevant for cell biology, such as adhesion forces, in a minimally invasive way. Optical tweezers have also been coupled with other techniques from cell biology in other to aid in the elucidation of signalling pathways that regulate processes such as binding or growth. Furthermore, optical tweezers have also been employed as a powerful means to alter and control the behaviour of cells, such as the rate and direction of growth of neurons. In this Chapter, we exemplify the application of optical tweezers to problems in cell biology reviewing in detail three examples: measurement of cellular adhesion forces, probing the structures by which bacteria bind to surfaces, and guiding the growth of neurons [Fig. 14.1].
14.1 Cellular adhesion forces
14.2 Adhesion and structure of bacterial pili
14.3 Directed neuronal growth
14.4 Further reading