MDCK Cystogenesis Driven by Cell Stabilization within Computational Analogues

University of California San Diego, United States of America
PLoS Computational Biology (Impact Factor: 4.62). 04/2011; 7(4):e1002030. DOI: 10.1371/journal.pcbi.1002030
Source: PubMed


The study of epithelial morphogenesis is fundamental to increasing our understanding of organ function and disease. Great progress has been made through study of culture systems such as Madin-Darby canine kidney (MDCK) cells, but many aspects of even simple morphogenesis remain unclear. For example, are specific cell actions tightly coupled to the characteristics of the cell's environment or are they more often cell state dependent? How does the single lumen, single cell layer cyst consistently emerge from a variety of cell actions? To improve insight, we instantiated in silico analogues that used hypothesized cell behavior mechanisms to mimic MDCK cystogenesis. We tested them through in vitro experimentation and quantitative validation. We observed novel growth patterns, including a cell behavior shift that began around day five of growth. We created agent-oriented analogues that used the cellular Potts model along with an Iterative Refinement protocol. Following several refinements, we achieved a degree of validation for two separate mechanisms. Both survived falsification and achieved prespecified measures of similarity to cell culture properties. In silico components and mechanisms mapped to in vitro counterparts. In silico, the axis of cell division significantly affects lumen number without changing cell number or cyst size. Reducing the amount of in silico luminal cell death had limited effect on cystogenesis. Simulations provide an observable theory for cystogenesis based on hypothesized, cell-level operating principles.

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Available from: Jesse A Engelberg,
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    • "Felodipine disposition characteristics are different, but the basic processes and general, subject physiology are assumed to be similar between the two studies, which allowed us to begin by adopting the earlier analog. We then followed the iterative refinement protocol to extend the analog phenotype and achieve the new set of validation targets without having to reengineer the whole system, and without compromising already validated features and behaviors [13], [14]. The protocol starts with specifying referent attributes to be targeted, e.g., drug and metabolite concentration-time data, histological and biochemical measurements, morphological characteristics, etc. Next, an initial (small) subset of attributes is selected, and an analog is constructed, tested, and revised iteratively until the analog exhibits the targeted attributes within a prespecified level of similarity, thereby achieving a level of validation. "
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    • "It is noteworthy that tight regulation of cyst size, shape and polarization is critical for normal kidney development and functions. Disruption of these regulatory mechanisms leads to an array of diseases including autosomal dominant polycystic kidney disease, stenosis, and cancer [37]. Our previous data [32] and current studies showed that in 3-D culture, p53 knockdown alone is unable to alter MDCK cell morphology, although the cells display enhanced proliferation and migration activities. "
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    PLoS ONE 12/2013; 8(12):e85624. DOI:10.1371/journal.pone.0085624 · 3.23 Impact Factor
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    • "In particular , it has not been demonstrated whether the simple aforementioned mechanistic principles are sufficient to reproduce cyst architectures. Furthermore, although it is clear that misorientation of the spindle is an ingredient leading to the aberrant multilumen phenotype (Zheng et al., 2010; Engelberg et al., 2011), it is not clear how and to what extent cyst architecture and orientation of cell division are related. To shed light on these issues, we developed a mathematical model based on the phenomenology of cell–cell and cell– matrix interactions that reproduces the experimentally observed phenotypes in both the normal and the aberrant cases. "
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