Migration mechanisms of corneal epithelial tissue and cells [thesis]

Beatrice Ann Dalton
2002
The aim of the research described in this thesis was to understand the underlying mechanisms for the migration of stratified epithelial tissue over synthetic surfaces. The hypothesis tested was that there are differences between the mechanisms that operate when intact epithelial tissue migrates and when individual cells migrate. The experimental approach taken was to compare the structure and functioning of cytoskeletal components within bovine corneal epithelial tissue and cells migrating over
more » ... synthetic substrata in vitro. Tissue and cell migration in response to two classes of surface topography were also considered. The component cells within migrating tissue remained attached to each other by means of inter-digitations of plasma membranes and by desmosomes. This permitted coordination between the tissue cells and restricted their independent movement. Basal cells throughout the tissue maintained contact with the substratum by focal adhesions and both marginal and submarginal basal cells were implicated as active participants in migration. The tissue cells situated anteriorly were transported by the basal cells and appeared not to actively participate in migration. Optimal rates of tissue and cell migration were dependent upon intact actin filament and microtubule systems. Migrating tissue maintained its morphological structure and integrity when cytoskeletal elements were disrupted, unlike migrating cells, which retracted when the actin filaments were disassembled. The basic sequence of mechanistic events that occurred during epithelial cell migration also occurred in relation to the cells within the tissue that were in contact with the substratum. The persistence of adhesion between the component cells within the migrating tissue added an element of complexity that was not encountered during cell migration and was manifested by This Thesis is dedicated to Joan Graham iii PUBLICATIONS DURING THE PhD CANDIDATURE The research for this thesis was conduced on a part-time basis between 1994 and 2001 at CSIRO, Molecular Science, North Ryde. Strategic research, related to the effect of surface topography on corneal epithelial tissue and cell migration, was conducted in parallel with the PhD research between 1995 and 2000 as part of the "Artificial Cornea" team. Relevant aspects of that published research are included in Chapter 5. Following is a list of journal articles and conference abstracts published during the PhD candidature detailing the relationship to the thesis (where applicable) and statements as to the extent of my contribution to the studies described in Chapter 5.
doi:10.26190/unsworks/13858 fatcat:np5lcj6qe5fgra2gdlprwa2oym