Enzyme therapy for lysosomal acid lipase deficiency in the mouse.
Lysosomal acid lipase (LAL) is the critical enzyme for the hydrolysis of the triglycerides (TG) and cholesteryl esters (CE) delivered to lysosomes. Its deficiency produces two human phenotypes, Wolman disease (WD) and cholesteryl ester storage disease (CESD). A targeted disruption of the LAL locus produced a null (lal( -/-)) mouse model that mimics human WD/CESD. The potential for enzyme therapy was tested using mannose terminated human LAL expressed in Pichia pastoris (phLAL), purified, and administered by tail vein injections to lal( -/-) mice. Mannose receptor (MR)-dependent uptake and lysosomal targeting of phLAL were evidenced ex vivo using competitive assays with MR-positive J774E cells, a murine monocyte/macrophage line, immunofluorescence and western blots. Following (bolus) IV injection, phLAL was detected in Kupffer cells, lung macrophages and intestinal macrophages in lal( -/-) mice. Two-month-old lal( -/-) mice received phLAL (1.5 U/dose) or saline injections once every 3 days for 30 days (10 doses). The treated lal( -/-) mice showed nearly complete resolution of hepatic yellow coloration; hepatic weight decreased by approximately 36% compared to PBS-treated lal( -/-) mice. Histologic analyses of numerous tissues from phLAL-treated mice showed reductions in macrophage lipid storage. TG and cholesterol levels decreased by approximately 50% in liver, 69% in spleen and 50% in small intestine. These studies provide feasibility for LAL enzyme therapy in human WD and CESD.
Du
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The Children's Hospital Research Foundation, Division of Human Genetics, 3333 Burnet Avenue, Cincinnati, OH 45229-3039, USA.
Schiavi
S
S
Levine
M
M
Mishra
J
J
Heur
M
M
Grabowski
G A
GA
D000818:Animals; D000906:Antibodies / Q000276:immunology; D002478:Cells, Cultured; D015217:Cholesterol Ester Storage Disease / Q000097:blood / Q000188:drug therapy* / Q000201:enzymology / Q000473:pathology; D004195:Disease Models, Animal; D016503:Drug Delivery Systems; D006801:Humans; D007124:Immunoenzyme Techniques; D007422:Intestines / Q000473:pathology; D037181:Lectins, C-Type; D008049:Lipase / Q000172:deficiency / Q000235:genetics / Q000276:immunology / Q000627:therapeutic use*; D008055:Lipids / Q000097:blood; D008099:Liver / Q000473:pathology; D008247:Lysosomes / Q000378:metabolism; D008264:Macrophages / Q000378:metabolism; D008297:Male; D000090323:Mannose Receptor; D037241:Mannose-Binding Lectins; D051379:Mice; D010641:Phenotype; D010843:Pichia; D011956:Receptors, Cell Surface / Q000378:metabolism; D011994:Recombinant Proteins / Q000235:genetics / Q000627:therapeutic use; D013154:Spleen / Q000473:pathology; D015223:Wolman Disease / Q000097:blood / Q000188:drug therapy* / Q000201:enzymology / Q000473:pathology
D000906:Antibodies; D037181:Lectins, C-Type; D008055:Lipids; D000090323:Mannose Receptor; D037241:Mannose-Binding Lectins; D011956:Receptors, Cell Surface; D011994:Recombinant Proteins; D008049:Lipase