Autoantibodies to lipoprotein lipase and dyslipidemia in systemic lupus erythematosus

Abstract

Objective. To demonstrate the binding of bovine lipoprotein lipase (LPL) by IgG from sera obtained from patients with systemic lupus erythematosus (SLE) and other rheumatic diseases, and the relationship of anti-LPL to triglyceride levels in SLE.Method. Binding of LPL by IgG from sera obtained from patients with SLE and other rheumatic diseases was measured by an enzyme-linked immunosorbent assay technique. Lipid profiles for fasting blood samples obtained from SLE patients and control subjects were determined.Results. Sera obtained from 105 patients with SLE were assessed for reactivity with LPL, and 49 (47%) of the results were positive. Sera obtained from patients with rheumatoid arthritis (RA) (n ‫؍‬ 80), Sjögren's syndrome (n ‫؍‬ 30), polymyositis and dermatomyositis (n ‫؍‬ 30), and progressive systemic sclerosis (n ‫؍‬ 31) were also studied, and 10 (13%), 3 (10%), 12 (40%), and 13 (42%), respectively, were positive for reactivity with LPL. It was determined that all affinity-purified antidouble-stranded DNA (dsDNA) antibodies and 4 of 5 monoclonal anti-dsDNA antibodies bound to LPL. The binding of IgG depleted of anti-dsDNA to LPL indicates a second anti-LPL activity in SLE. Measurements of fasting lipid levels in SLE patients with anti-LPL revealed a strong positive correlation of antibody levels and total serum triglycerides, apolipoprotein B, and apolipoprotein E concentrations.Conclusion. Antibodies to LPL occurred in 47% of SLE patients and in a similar percentage of patients with polymyositis or systemic sclerosis. The prevalence of these antibodies was less in patients with RA or Sjögren's syndrome. It is hypothesized that the elevated triglyceride levels in SLE patients are in part attributable to anti-LPL, and this lipid abnormality could contribute to the premature atherosclerosis known to be present in patients with SLE.

Estudo longitudinal do anticorpo antilipoproteína lipase e sua relação com atividade de doença nos indivíduos com lúpus eritematoso sistêmico sem anticorpos anti-dsDNA

“…This brings to light the question previously raised by Reichlin of distinct subpopulations of autoantibodies against LPL, perhaps there is a population that has an inhibitory activity on the enzyme and other population not functionally active. 4 Our study showed titer fluctuation of anti-LPL antibodies in those individuals with concomitant lupus clinical and laboratory activity. On the other hand, in those other patients who were in remission for years, anti-LPL antibodies were present, in high titers and with no significant variation.…”

“…Nesse sentido, os anticorpos antilipoproteína lipase (anti-LPL), recentemente descritos no LES 4 , foram correlacionados à hipertrigliceridemia, à proteína C-reativa de alta sensibilidade e à atividade de doença através do systemic lupus erythematosus disease activity index (SLEDAI). 5 A lipoproteína lipase (LPL) é uma enzima presente na superfície endotelial que tem como função a hidrólise de quilomícrons e triglicérides 6 e já foi demonstrada que a sua função reduzida está relacionada à hipertrigliceridemia.…”

“…Isso sugere a presença de duas subpopulações de anticorpos anti-LPL, uma relacionada à atividade de doença e que acompanha a evolução de atividades e remissões dos indivíduos e outra subpopulação de anticorpos que se mantém elevada persistentemente, não se correlacionando com atividade ou mesmo com níveis dos lipídios sanguíneos, como já explicado anteriormente. 4 Este estudo traz a possibilidade de um novo e possível marcador de atividade do LES quando os anticorpos antidsDNA estão ausentes no soro de alguns pacientes com essa conectivopatia.…”

“…Recently described in SLE, 4 anti-lipoprotein lipase antibodies (anti-LPL), was correlated to hypertriglyceridemia, and to highly sensitive C-reactive protein, and the Systemic Lupus Erythematosus Activity Index (SLEDAI). 5 Lipoprotein lipase (LPL) is an enzyme present in endothelial surface, which function is hydrolysis of chylomicrons and triglycerides, 6 and it has already been demonstrated that its reduced function is related to hypertriglyceridemia.…”

Plasma Atherogenic Index is an Independent Indicator of Subclinical Atherosclerosis in Systemic Lupus Erythematosus

“…Furthermore, lipoprotein lipase antibodies in SLE patients can contribute to the high TG levels. The alterations in the TG metabolism can cause changes primarily in HDL and also other lipids [14,15]. The reasons for low HDL levels are the apoprotein A-1 synthesis in the liver and alterations in the lecithin cholesterol acyl transferase activity.…”