Oxidized low density lipoprotein--an extreme example of lipoprotein heterogeneity

The intense interest in the possibility that oxidative modification of low density lipoprotein (LDL) plays an important role in atherogenesis has led to an explosion in the number of papers dealing one way or another with "oxidized LDL". A great deal has been learned about the biological properties of "oxidized LDL", the complex chemical processes accompanying oxidation and its pathogenetic role in experimental animal models. Yet the term itself--"oxidized LDL"--is woefully inadequate. In this short essay to honor the memory of my friend and colleague, Shlomo Eisenberg, I will attempt to indicate the questions that need to be asked; I do not provide the answers.