title: Multi-type branching models to describe cell differentiation programs.
abstract: Cell proliferation and differentiation is described by a multi-type branching process, a probability model that defines the inheritance of cell type. Cell type is defined by (i) a repression index related to the time required for S-phase entry and (ii) phenotype as determined by cell markers and division history. The inheritance of cell type is expressed as the expected number and type of progeny cells produced by a mother cell given her type. Expressions for the expected number and type of cells produced by a multi-cellular (bulk culture) system are derived from the general model by making the simplifying assumption that cell generation times are independent. The multi-type Smith-Martin model (MSM) makes the further assumption that cell generation times are lag-exponentially distributed with phenotype transitions occurring just before entry into S-phase. The inheritance-modified MSM (IMSM) model includes the influence of generation time memory so that mother and daughter generation times are correlated. The expansion of human cord blood CD34(+) cells by haematopoietic growth factors was division tracked in bulk culture using carboxyfluorescein diacetate, succinimidyl ester (CFDA-SE). The MSM model was fitted to division tracking data to identify cell cycle length, and the rates of CD34 antigen down-regulation and apoptosis. The IMSM model was estimated for mouse granulocyte-macrophage progenitors using live cell imaging data. Multi-type branching models describe cell differentiation dynamics at both single- and multi-cell scales, providing a new paradigm for systematic analysis of stem and progenitor cell development.
authors.affiliation: Graduate School of Biomedical Engineering, University of New South Wales, Sydney 2052, Australia. r.nordon@unsw.edu.au
authors.forename: Robert E
authors.initials: RE
authors.lastname: Nordon
authors.forename: Kap-Hyoun
authors.initials: KH
authors.lastname: Ko
authors.forename: Ross
authors.initials: R
authors.lastname: Odell
authors.forename: Timm
authors.initials: T
authors.lastname: Schroeder
mesh_terms: D000818:Animals; D018952:Antigens, CD34 / Q000378:metabolism; D002454:Cell Differentiation / Q000187:drug effects; D049109:Cell Proliferation / Q000187:drug effects; D002999:Clone Cells; D003198:Computer Simulation; D016207:Cytokines / Q000494:pharmacology; D005312:Fetal Blood / Q000166:cytology; D006801:Humans; D051379:Mice; D008954:Models, Biological; D010641:Phenotype; D013997:Time Factors
chemical_list: D018952:Antigens, CD34; D016207:Cytokines