Synergistic activity of polarised osteoblasts inside condensations cause their differentiation

Authored by Himanshu Kaul, Yiannis Ventikos, Brian K Hall, Chris Newby

Date Published: 2015

DOI: 10.1038/srep11838

Sponsors: National Science and Engineering Research Council of Canada (NSERC)

Platforms: FLAME

Model Documentation: Other Narrative Mathematical description

Model Code URLs: Model code not found

Abstract

Condensation of pre-osteogenic, or pre-chondrogenic, cells is the first of a series of processes that initiate skeletal development. We present a validated, novel, three-dimensional agent-based model of in vitro intramembranous osteogenic condensation. The model, informed by system heterogeneity and relying on an interaction-reliant strategy, is shown to be sensitive to `rules' capturing condensation growth and can be employed to track activity of individual cells to observe their macroscopic impact. It, therefore, makes available previously inaccessible data, offering new insights and providing a new context for exploring the emergence, as well as normal and abnormal development, of osteogenic structures. Of the several stages of condensation we investigate osteoblast `burial' within the osteoid they deposit. The mechanisms underlying entrapment required for osteoblasts to differentiate into osteocytes - remain a matter of conjecture with several hypotheses claiming to capture this important transition. Computational examination of this transition indicates that osteoblasts neither turn off nor slow down their matrix secreting genes - a widely held view; nor do they secrete matrix randomly. The model further reveals that osteoblasts display polarised behaviour to deposit osteoid. This is both an important addition to our understanding of condensation and an important validation of the model's utility.

Tags

Rat calvaria cells Nodules formed invitro Bone nodules Skeletal development Osteogenesis Osteocytes Biology