Likelihood-based heterogeneity inference reveals nonstationary effects in biohybrid cell-cargo transport

Variability of motility behavior in populations of microbiological agents is a ubiquitous phenomenon even in the case of genetically identical cells. Accordingly, passive objects introduced into such biological systems and driven by them will also exhibit heterogeneous motion patterns. Here, we study a biohybrid system of passive beads driven by active ameboid cells and use a likelihood approach to estimate the heterogeneity of the bead dynamics from their discretely sampled trajectories. We showcase how this approach can deal with information-scarce situations and provides natural uncertainty bounds for heterogeneity estimates. Using these advantages, we particularly uncover that the heterogeneity in the system is time-dependent.