Formation of ox-LDL in the Inflamed Human Joint

It has been pointed out that some of the histopatholog-ical changes in rheumatoid synovitis are similar to those noted adjacent to atherosclerotic plaques. For example, accumulation of mononuclear cells at the extraluminal surface of endothelial cells in the adventitia and the deposition of immune complexes have been reported in both diseases (Rothschild and Masi, 1982). 

It is unlikely that the damaging effects of ox-LDL are relevant only to the walls of blood vessels and there is no reason to suppose they are confined to one disease. The initial histopathologjcal sign of coronary heart disease is the appearance of the fetty streak on the luminal surfece of arteries. Fatty streaks are composed of aggregated macrophages that have taken up ox-LDL via the scavenger receptor. Recently, we have detected such foam cells in the rheumatoid synovium (Section 5.5). 

The peroxidation of LDL occurs after depletion of the molecule s inherent antioxidants. Other characteristics of 

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