Analysis of Protein Localization in Neutrophil Chemotaxis Using Microfluidic Gradient Platforms

Eukaryotic chemotaxis is a complex process initiated by morphological polarization in response to concentration gradients of chemoattractants. During this process, a number of regulatory protein and lipid signaling molecules are selectively recruited to either the front or back of the migrating cell. While much is known about how their location determines the orientation of the cell and direction of migration, the detailed mechanisms underlying the process still remain unclear.

The goal of this work is to investigate the localization of key regulatory molecules such as actin and AKT involved in neutrophil chemotaxis. To this end, we tagged proteins of interest with fluorescent labels in HL-60 cell lines and monitored their localization while cells migrated in gradients created using microfluidic platforms. By analysis of localization of proteins involved in signaling pathways under different gradient conditions, we have begun to elucidate how external gradient conditions influence the internal distribution of these proteins. These results provide insight into neutrophil regulatory mechanisms and should aid in design of novel therapeutic strategies to treat immune-based disorders.