title: Effect of recombinant human lecithin cholesterol acyltransferase infusion on lipoprotein metabolism in mice.
abstract: Lecithin cholesterol acyl transferase (LCAT) deficiency is associated with low high-density lipoprotein (HDL) and the presence of an abnormal lipoprotein called lipoprotein X (Lp-X) that contributes to end-stage renal disease. We examined the possibility of using LCAT an as enzyme replacement therapy agent by testing the infusion of human recombinant (r)LCAT into several mouse models of LCAT deficiency. Infusion of plasma from human LCAT transgenic mice into LCAT-knockout (KO) mice rapidly increased HDL-cholesterol (C) and lowered cholesterol in fractions containing very-low-density lipoprotein (VLDL) and Lp-X. rLCAT was produced in a stably transfected human embryonic kidney 293f cell line and purified to homogeneity, with a specific activity of 1850 nmol/mg/h. Infusion of rLCAT intravenously, subcutaneously, or intramuscularly into human apoA-I transgenic mice showed a nearly identical effect in increasing HDL-C approximately 2-fold. When rLCAT was intravenously injected into LCAT-KO mice, it showed a similar effect as plasma from human LCAT transgenic mice in correcting the abnormal lipoprotein profile, but it had a considerably shorter half-life of approximately 1.23 ± 0.63 versus 8.29 ± 1.82 h for the plasma infusion. rLCAT intravenously injected in LCAT-KO mice crossed with human apolipoprotein (apo)A-I transgenic mice had a half-life of 7.39 ± 2.1 h and increased HDL-C more than 8-fold. rLCAT treatment of LCAT-KO mice was found to increase cholesterol efflux to HDL isolated from mice when added to cells transfected with either ATP-binding cassette (ABC) transporter A1 or ABCG1. In summary, rLCAT treatment rapidly restored the normal lipoprotein phenotype in LCAT-KO mice and increased cholesterol efflux, suggesting the possibility of using rLCAT as an enzyme replacement therapy agent for LCAT deficiency.
authors.affiliation: Pulmonary and Vascular Medicine Branch, Lipoprotein Metabolism Section, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD 20892, USA. roussetx@mail.nih.gov
authors.forename: Xavier
authors.initials: X
authors.lastname: Rousset
authors.forename: Boris
authors.initials: B
authors.lastname: Vaisman
authors.forename: Bruce
authors.initials: B
authors.lastname: Auerbach
authors.forename: Brian R
authors.initials: BR
authors.lastname: Krause
authors.forename: Reyn
authors.initials: R
authors.lastname: Homan
authors.forename: John
authors.initials: J
authors.lastname: Stonik
authors.forename: Gyorgy
authors.initials: G
authors.lastname: Csako
authors.forename: Robert
authors.initials: R
authors.lastname: Shamburek
authors.forename: Alan T
authors.initials: AT
authors.lastname: Remaley
mesh_terms: D000818:Animals; D001057:Apolipoproteins E / Q000378:metabolism; D002784:Cholesterol / Q000378:metabolism; D002788:Cholesterol Esters / Q000378:metabolism; D006224:Cricetinae; D006801:Humans; D007262:Infusions, Intravenous; D050356:Lipid Metabolism / Q000187:drug effects; D008074:Lipoproteins / Q000378:metabolism*; D008079:Lipoproteins, VLDL / Q000378:metabolism; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D007862:Phosphatidylcholine-Sterol O-Acyltransferase / Q000008:administration & dosage / Q000235:genetics / Q000494:pharmacology*; D011994:Recombinant Proteins
chemical_list: D001057:Apolipoproteins E; D002788:Cholesterol Esters; D008074:Lipoproteins; D008079:Lipoproteins, VLDL; D011994:Recombinant Proteins; D002784:Cholesterol; D007862:Phosphatidylcholine-Sterol O-Acyltransferase