Four dimensional analysis of vesicle dynamics during cell migration

Project completed in 2014. 

Dr Josh Rappoport, School of Biosciences
Professor John Heath, School of Biosciences
Dr Mike Ward, School of Mechanical Engineering
Professor Ela Claridge, School of Computer Science

Chemotaxis is the directed motility of cells within a gradient of a soluble chemoattractant. It underlies numerous biomedically relevant processes, for example movement of the immune system cells in the direction of pathogenic bacteria, repair of injured blood vessels and the metastatic spread of cancer cells.

Important biological issues include understanding the interplay between the signalling and trafficking of activated chemoattractant receptors and regulation of the cytoskeleton and adhesion modules. Greater understanding of intra- and inter-cellular mechanisms regulating chemotaxis will permit the development of therapeutic interventions, so that in some cases it can be augmented (e.g. angiogenesis) and in other situations inhibited (e.g. metastasis).

Progress in this domain depends on the development of sophisticated image analysis methods involving several microscopy modalities, and on the ability to conduct high-throughput analyses, e.g. in the context of pharmaceutical screening.

In addressing the first aspect, this project will develop imaging protocols and image analysis software capable of seamlessly tracking fluorescently tagged entities of interest, such as membrane proteins and vesicles, imaged quasi-simultaneously through both confocal and total internal reflection fluorescence (TIRF) microscopy. The analysis of intra-cellular dynamics will need to be carried out in context of cell motility, necessitating the capture of the movement of the actual cells involved in chemotaxis. To our knowledge this project will deliver the first such integrated analysis of sub-cellular events occurring during chemotaxis in live cells.