Introducing simulated stem cells into a bio-inspired cell-cell communication mechanism for structure regeneration

The planarian flatworm has been essential for learning about the regeneration process of organisms. One of the reasons for this exceptional capability is the abundance of adult stem cells, denominated neoblasts, distributed throughout planarian's body. Its body contains around 20% to 30% of neoblasts. Moreover, experiments in vivo show that irradiated worms with no neoblasts lose their regenerative capabilities. In this paper we add the concept of simulated neoblasts to a previous bio-inspired cell-cell communication mechanism of dynamic structure discovery and regeneration. We simulate a 3D organism structure resembling the planarian's, with the inclusion of two types of cells: the neoblasts that are capable of creating new morphological messages (packets) and differentiated cells that only relay such messages. After a cut in half, the mechanism uses morphological information created by neoblasts and exchanged across cells to regrow the missing tissue. We vary model parameters such as the frequency of packets created by neoblasts, how many segments a packet might have before backtracking, and the probability of a packet changing direction. After a large number of simulation runs, we confirm the efficacy of the model for distinct proportions of neoblasts, showing that there exist parameter assignments that fully regenerated the worm, even for simulations containing 10% of neoblasts.