Noise propagation and amplification mechanisms in stem cell differentiation via stochastic dynamics modelling

Stem cell differentiation is dynamically regulated by internal and external factors, with noise propagation critically influencing fate decisions and differentiation efficiency. To study the propagation and amplification of noise during stem cell differentiation, this paper proposed a dynamics model of stem cell differentiation. It investigated the noise propagation mechanism by applying a linear noise approximation to the master equation and introducing a noise propagation formula. Moreover, the effect of the net proliferative capacity of stem cells on noise propagation was investigated, revealing how specific parameters influence noise propagation by modulating cell behavior during differentiation. It was found that lower noise levels correlate with a higher steady-state cell number, indicating that noise affects cell stability. Furthermore, for source stem cells, total noise consists only of pure intrinsic noise, whereas for differentiated cells, total noise is affected by intercellular interactions. Regardless of whether differentiated cells can transform into each other, during differentiation, pure intrinsic noise usually accounts for the major part of total noise, with transmitted noise as a minor component and conversion noise being negligible. These findings provide new insights into understanding stochasticity in stem cell differentiation and a theoretical basis for optimizing stem cell therapy.