Technical Advance: Introducing a novel metric, directionality time, to quantify human neutrophil chemotaxis as a function of matrix composition and stiffness

摘要: A direct consequence of cellular movement and navigation, migration incorporates elements speed, direction, persistence motion. Current techniques to parameterize the trajectory a chemotaxing cell most commonly pair speed with some measure by calculating MSD, RMS TAD, and/or CI. We address inherent limitations in TAD CI for comparative analysis introducing two new analytical tools quantify persistence: directionality index time. With use these tools, we show that mechanical properties underlying substrate contribute significantly regulation human neutrophil chemotaxis toward fMLP on Fgn-, Col-, Fn-coated gels varying elasticity. The β1-integrin ligand Col demonstrated mechanosensitive speed. In contrast, β2-integrin Fgn supported persistence. Fn, recognized β1 β2 integrins, mechanoregulated Blocking integrins cells migrating Fn identified an β2-integrin-directed modulation These data demonstrate individual components chemotactic response integrin dependence are finely tunable different ligand, mechanotactic, cues, underscoring need sensitive methods.