Abnormalities of apolipoprotein E in the acquired immunodeficiency syndrome.

Given the important role of apolipoprotein E (apoE) in triglyceride metabolism, we analyzed plasma levels and degree of sialylation of apoE in subjects with the acquired immunodeficiency syndrome (AIDS), a disorder accompanied by hypertriglyceridemia. Levels of apoE were significantly increased (1.84-fold) and correlated with plasma triglycerides (r = .663, P < .001) in AIDS. Subjects with AIDS and the apoE3/E2 phenotype showed the most prominent increases in both plasma triglyceride and apoE levels (3.4 and 2.2-fold over controls). Additionally, apoE from subjects with AIDS showed an increased amount of sialylation, compared with controls (34% increase in apoE3/E3 subjects). Increased sialylation correlated with the increase in apoE levels. In contrast, there was no increase in sialylation of apo C-III in AIDS. Thus, triglyceride levels in AIDS are influenced by apoE subtype and subjects with AIDS show changes in apoE structure.