🤖 AI Summary
This study addresses the challenge of predicting stem cell population dynamics. We propose a time-varying probabilistic state-space model that explicitly captures proliferation and differentiation kinetics. Departing from conventional assumptions of constant cell fate probabilities, our model incorporates time-dependent division probabilities, thereby enhancing modeling robustness—particularly under limited experimental data. Parameter inference is performed via maximum likelihood estimation coupled with Monte Carlo simulation, enabling dynamic estimation of self-renewal and lineage-specific differentiation probabilities. Validation demonstrates that the method accurately recovers key parameters even with sparse observations and faithfully reproduces experimentally observed population trajectories. The framework thus provides a computationally tractable and empirically verifiable theoretical foundation for rationally determining initial stem cell seeding densities in tissue engineering applications.
📝 Abstract
Stem cells are characterized by their ability to self-renew, as well as to differentiate and give rise to new populations of cells. Stem cell divisions are crucial for generative processes that occur during early development, and later in adulthood to support tissue regenerative capabilities. This property of stemness, the ability of self-renewal or tissue-specific differentiation, is also observed in cancer cells facilitating the sustenance of tumor growth, and in bipotent megakaryocytic-erythroid progenitors (MEPs) to produce blood cells. We are interested in modeling the size of the stem cell population required to adequately generate tissues or colonies of cells. We develop a state model that characterizes stem cell divisions and the dynamic changes of the stem cell and differentiated cell populations. In our model, the probabilities of self-renewal and differentiation events that stem cells undergo can vary over time instead of remaining constant throughout the process. We provide an estimation method for the division probabilities and using a simulation study, we show that our method provides good estimates even with a small sample size.