title: Fluctuations of cell population in a colonic crypt.
abstract: The number of stem cells in a colonic crypt is often very small, which leads to large intrinsic fluctuations in the cell population. Based on the model of cell population dynamics with linear feedback in a colonic crypt, we present a stochastic dynamics of the cell population [including stem cells (SCs), transit amplifying cells (TACs), and fully differentiated cells (FDCs)]. The Fano factor, covariance, and susceptibility formulas of the cell population around the steady state are derived by using the Langevin theory. In the range of physiologically reasonable parameter values, it is found that the stationary populations of TACs and FDCs exhibit an approximately threshold behavior as a function of the net growth rate of TACs, and the reproductions of TACs and FDCs can be classified into three regimens: controlled, crossover, and uncontrolled. With the increasing of the net growth rate of TACs, there is a maximum of the relative intrinsic fluctuations (i.e., the Fano factors) of TACs and FDCs in the crossover region. For a fixed differentiation rate and the net growth rate of SCs, the covariance of fluctuations between SCs and TACs has a maximum in the crossover region. However, the susceptibilities of both TACs and FDCs to the net growth rate of TACs have a minimum in the crossover region.
authors.affiliation: Department of Physics and Institute of Biophysics, Central China Normal University, Wuhan 430079, China and School of Physical Science and Technology, Yangtze University, Jingzhou 434023, China.
authors.forename: Qi-ming
authors.initials: QM
authors.lastname: Pei
authors.affiliation: Department of Physics and Institute of Biophysics, Central China Normal University, Wuhan 430079, China.
authors.forename: Xuan
authors.initials: X
authors.lastname: Zhan
authors.affiliation: Department of Physics and Institute of Biophysics, Central China Normal University, Wuhan 430079, China.
authors.forename: Li-jian
authors.initials: LJ
authors.lastname: Yang
authors.affiliation: Department of Physics and Institute of Biophysics, Central China Normal University, Wuhan 430079, China.
authors.forename: Chun
authors.initials: C
authors.lastname: Bao
authors.affiliation: Department of Physics and Institute of Biophysics, Central China Normal University, Wuhan 430079, China and College of Science, Huazhong Agricultural University, Wuhan 430070, China.
authors.forename: Wei
authors.initials: W
authors.lastname: Cao
authors.affiliation: Department of Physics and Institute of Biophysics, Central China Normal University, Wuhan 430079, China.
authors.forename: An-bang
authors.initials: AB
authors.lastname: Li
authors.affiliation: Department of Physics and Institute of Biophysics, Central China Normal University, Wuhan 430079, China and Department of Physics, Kashgar Teachers College, Kashgar 844007, China.
authors.forename: Anvar
authors.initials: A
authors.lastname: Rozi
authors.affiliation: Department of Physics and Institute of Biophysics, Central China Normal University, Wuhan 430079, China.
authors.forename: Ya
authors.initials: Y
authors.lastname: Jia
mesh_terms: D002454:Cell Differentiation / Q000502:physiology; D002478:Cells, Cultured; D003106:Colon / Q000166:cytology* / Q000502:physiology*; D003198:Computer Simulation; D020895:Enterocytes / Q000166:cytology* / Q000502:physiology*; D006801:Humans; D008954:Models, Biological; D015233:Models, Statistical; D013234:Stem Cells / Q000166:cytology* / Q000502:physiology*