Chemotaxis-driven Instabilities govern size, shape and migration efficiency of multicellular clusters

This dataset documents experimental and simulation-based measurements of collective chemotactic migration and dynamical behavior of multicellular cell clusters. It includes processed experimental data derived from time-lapse microscopy of chronic lymphocytic leukemia (CLL) cell clusters exposed to controlled gradients of the chemokine CCL19 (0–100 ng ml⁻¹ mm⁻¹). Image-based measurements were extracted using Fiji/ImageJ and include cluster size, centroid trajectories, migration velocities, shape descriptors, and orientation of the cluster’s major axis relative to the chemical gradient, reported in pixel units. The dataset also contains processed outputs from particle-based and agent-based simulations spanning multiple cluster sizes and gradient strengths. Simulation variables include forward migration index, mixing entropy, spatial and orientational correlations, shape metrics, rotational dynamics, and cluster breaking frequencies. Scripts used to compute quantitative metrics and reproduce summary analyses are provided. Together, these data support quantitative analyses of collective chemotactic responses, shape deformation, and instability-driven dynamics in multicellular systems and provide reusable benchmarks for studies of collective migration and active matter.