Characteristics of cell motility during cell collision

Quantitative examination of cellular motion and intercellullar interactions possesses substantial relevance for both biology and medicine. However, the effects of intercellular interactions during cellular locomotion remain under-explored in experimental research. As such, this study seeks to bridge this research gap, adopting Dictyostelium discoideum (Dicty) cells as a paradigm to investigate variations in cellular motion during reciprocal collisions. We aim to attain a comprehensive understanding of how cell interactions influence cell motion. By observing and processing the motion trajectories of colliding cells under diverse chemical environments, we calculated the diffusion coefficient (D) and the persistence time (τ), using mean square displacement. Our analysis of the relationship dynamics between D and τ prior to the collisions reveals intricate and non-monotonic alterations in cell movements during collisions. By quantitatively scrutinizing the τ trend, we were able to categorize the cellular responses to interactions under different conditions. Importantly, we ascertained that the effect of cell interactions during collisions in Dicty cells emulates a classical sigmoid function. This discovery suggests that cellular responses might comply with a pattern akin to the Weber-Fechner law.