First 11 pages of thesis. - OPUS - Universität Würzburg

Figure 1: Structure of a normal vessel wall. The cross sectional view shows the three distinct
layers of the vessel wall: the intima, media and adventitia. (Picture from Lusis AJ, Nature. 2000;
407(6801):233-41)
During the initial stages, lipoproteins and their aggregates accumulate in
the intima of the vessel wall, at sites of lesion predilection. These predilection
sites are usually the branching points or the inner curvature of the arteries,
where normal blood flow dynamics are altered 1 . Subsequently, monocytes and
lymphocytes adhere to the endothelium, transmigrate across the endothelial
layer into the intima of the vessel where they proliferate, differentiate and take
up lipoproteins to form “foam cells”. Though these early plaques or foam cells
(also termed as ‘fatty streaks’) are not of clinical significance, they are the
precursors of advanced lesions. As the disease progresses the foam cells die
and the smooth muscle cells migrate from the medial layer into the intima,
where they accumulate and proliferate. The so called advanced lesions are
characterised by the accumulation of smooth muscle cells and dead foam cells,
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