Mary Myerscough

Title

A Structured Population Model for Lipid Accumulation in Macrophages during Atherosclerotic Plaque Development

Abstract

Macrophages are typical cells that are found in atherosclerotic plaques and may contribute either to plaque growth or to plaque resolution.  Macrophages accumulate internalised lipids, such as cholesterol, both through ingesting modified low density lipoprotein particles (modLDL) and through ingesting other macrophages that have undergone apoptosis (programmed cell death).  In this way macrophages may accumulate so much internalised lipid that they take on a foamy appearance under the microscope and are known as foam cells. 

We present an advective PDE model for the populations of macrophages and apoptotic cells, structured by their internalised lipid content.  We find steady state solutions analytically and use this model to explore the factors that contribute to plaque progression and regression. The model shows impressive agreement with {\it in vitro} experiments in the case when lipid accumulation is due to ingestion of apoptotic cells only.  The results of this research suggest that tracking lipids, both in cell membranes and in modLDL is just as important as tracking macrophage numbers in modelling plaque development.

Short bio

Mary Myerscough received her first degrees in Applied Mathematics from the University of Sydney and then completed her D.Phil at Oxford University at the Centre for Mathematical Biology, supervised by Jim Murray.  As part of her DPhil, she worked with Philip Maini on bifurcations in models for two dimensional chemotactic pattern. Mary has worked on problems in social insect behaviour in collaboration with biological scientists at Sydney University, Macquarie University and CSIRO.  More recently she has developed a strong interest in modelling the immunology of atherosclerotic plaque development. Mary is Professor of Mathematical Biology and Associate Head of School (Education) in the School of Mathematics and Statistics at the University of Sydney.