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At least 253 records · Page 14Linked to original sources
PubMed1977

Enzyme replacement therapy in Gaucher's disease: preliminary clinical trial of a new enzyme preparation.

A patient with far-advanced adult type Gaucher's disease was treated with solubilized, highly purified placental glucocerebrosidase administered after entrapment in human erythrocytes or by direct intravenous injection. In some instances the enzyme-containing erythrocytes were coated with gamma globulin. No toxic side effects were observed after enzyme infusion. There were suggestive, but not conclusive, findings that enzyme infusion may have been beneficial. After therapy, there was a decrease in transfusion requirement, some improvement of liver function, possible decrease in liver size, and relief of subjective symptoms. Erythrocyte and plasma glucocerebroside levels were unchanged during therapy, but there was a possibly significant decrease in leukocyte and platelet levels of the glycolipid. No changes occurred in serum acid phosphatase or angiotensin-converting enzyme activity.

Acid Phosphatase↗
PubMed1993

Enzyme replacement therapy with polyethylene glycol-adenosine deaminase in adenosine deaminase deficiency: overview and case reports of three patients, including two now receiving gene therapy.

During the past 6 y, 29 adenosine deaminase (ADA)-deficient patients with combined immunodeficiency have been treated with polyethylene glycol (PEG)-modified bovine ADA (PEG-ADA). We have monitored plasma ADA activity, metabolic effects of treatment, and the evolution of antibody to PEG-ADA in these patients, in collaboration with immunologists and clinicians in North America, Europe, and Australia, who have monitored immune function and clinical response to treatment. This article summarizes the current status of PEG-ADA therapy and provides recommendations for its use. Recovery of specific immune function during treatment with PEG-ADA is illustrated for three patients, who represent early, delayed, these patients have entered a trial of gene therapy, but continue to receive enzyme replacement.

Adenosine Deaminase↗
PubMed1979

Enzyme replacement therapy by fibroblast transplantation: long-term biochemical study in three cases of Hunter's syndrome.

We have assessed the effectiveness of transplanted histocompatible fibroblasts as a long-lived source of lysosomal enzymes for replacement therapy in three patients with Hunter's syndrome, over periods ranging from 2.5 to 3.75 yr. The level of Hunter corrective factor excreted by all three patients increased after transplantation, as did the activity of alpha-L-idurono-2-sulfate sulfatase in serum, when measured directly with a radioactive disulfated disaccharide substrate. Sulfatase activity was also raised in leukocyte homogenates from the two patients that we were able to assess. These increases in enzyme activity were accompanied by corresponding increases in catabolism of heparan and dermatan sulfates, as shown by (a) a decrease in sulfate:uronic ratios of urinary oligosaccharides, (b) an increase in iduronic acid monosaccharide, and (c) a normalization of Bio-Gel P-2 gel filtration profiles. Both the increase in enzyme activity and increased catabolism were maintained during the period of study and were not affected by either a gradual decrease or total withdrawal of immunosuppressive therapy.

Child↗
PubMed2002

Gaucher disease with nephrotic syndrome: response to enzyme replacement therapy.

Nephrotic syndrome in patients with Gaucher disease is rare; most of the few reported cases have had a well-defined glomerulopathy often with Gaucher cells in the glomeruli. We report the case of a 54-year-old woman with Gaucher disease, who had splenectomy at age 25, preeclampsia with renal biopsy disclosing only endotheliosis at age 32, and improvement of proteinuria and reappearance of heavy proteinuria (7.2 g/24 h) at age 41. Renal biopsy disclosed Gaucher cells in glomeruli and interstitium. The patient did not receive therapy specifically for glomerular disease. Enzyme replacement, begun 4 years later and maintained until now, was associated with amelioration of systemic symptoms and virtual disappearance of proteinuria with a follow-up of 10 years. This case apparently is the first instance of nephrotic syndrome consequent to Gaucher disease itself and successful treatment with specific enzyme replacement.

Endothelium, Vascular↗
PubMed1981

Biochemical and functional abnormalities in lymphocytes from an adenosine deaminase-deficient patient during enzyme replacement therapy.

Biochemical and immunological properties of lymphocytes were measured repetitively over a period of 40 mo during enzyme replacement by transfusion in a child with adenosine deaminase (ADA) deficiency and severe combined immunodeficiency disease. Catalytically defective ADA protein is present in the child's cells. ADA activity in his lymphocytes is 7 nmol/min per 10(8) cells with 51 ng of ADA protein/10(8) cells by radioimmunoassay. ADA activities in normal cord and adult lymphocytes average 193 and 92 nmol/min per 10(8) cells, respectively, with 429 and 223 ng of ADA protein/10(8) cells. Deoxy(d)ATP accumulates in the patient's erythrocytes and lymphocytes. Transfusion of irradiated packed erythrocytes partially corrects the metabolic defects. Frank metabolic relapse occurs if transfusions are discontinued for several months. The amounts of dATP in erythrocytes and lymphocytes averaged 13 and 2 times normal, respectively, during periods when transfusions were administered every 2-4 wk. Deoxyguanosine triphosphate and deoxycytidine triphosphate in lymphocytes were normal on 11 occasions, but deoxyribosylthymine triphosphate was ninefold increased. On 11 occasions dATP was measured in lymphocytes and erythrocytes isolated simultaneously. There was a positive, but statistically insignificant, correlation between amounts of dATP in the two types of cells (r = 0.25,P > 0.1). The absolute peripheral lymphocyte count was correlated with the activity of ADA in circulating erythrocytes and with the response of lymphocytes to phytohemagglutinin (r = 0.64, P < 0.01; r = 0.49, P < 0.05). Response of lymphocytes to stimulation by phytohemagglutinin in vitro and absolute peripheral lymphocyte counts were not significantly correlated with levels of dATP in the erythrocyte or lymphocyte during periods of intensive therapy. Although there was objective improvement during enzyme replacement, the child remained immunodeficient and biochemically abnormal.

Adenosine Deaminase↗
PubMed2005

The role of mannosylated enzyme and the mannose receptor in enzyme replacement therapy.

Lysosomal acid lipase (LAL) is the critical enzyme for the hydrolysis of triglycerides (TGs) and cholesteryl esters (CEs) in lysosomes. LAL defects cause Wolman disease (WD) and CE storage disease (CESD). An LAL null (lal-/-) mouse model closely mimics human WD/CESD, with hepatocellular, Kupffer cell and other macrophage, and adrenal cortical storage of CEs and TGs. The effect on the cellular targeting of high-mannose and complex oligosaccharide-type oligosaccharide chains was tested with human LAL expressed in Pichia pastoris (phLAL) and CHO cells (chLAL), respectively. Only chLAL was internalized by cultured fibroblasts, whereas both chLAL and phLAL were taken up by macrophage mannose receptor (MMR)-positive J774E cells. After intraperitoneal injection into lal-/- mice, phLAL and chLAL distributed to macrophages and macrophage-derived cells of various organs. chLAL was also detected in hepatocytes. Ten injections of either enzyme over 30 d into 2- and 2.5-mo-old lal-/- mice produced normalization of hepatic color, decreased liver weight (50%-58%), and diminished hepatic cholesterol and TG storage. Lipid accumulations in macrophages were diminished with either enzyme. Only chLAL cleared lipids in hepatocytes. Mice double homozygous for the LAL and MMR deficiences (lal-/-;MMR-/-) showed phLAL uptake into Kupffer cells and hepatocytes, reversal of macrophage histopathology and lipid storage in all tissues, and clearance of hepatocytes. These results implicate MMR-independent and mannose 6-phosphate receptor-independent pathways in phLAL uptake and delivery to lysosomes in vivo. In addition, these studies show specific cellular targeting and physiologic effects of differentially oligosaccharide-modified human LALs mediated by MMR and that lysosomal targeting of mannose-terminated glycoproteins occurs and storage can be eliminated effectively without MMR.

Animals↗
PubMed1980

Immunologic aspects of enzyme replacement therapy. An evaluation of the immune response to unentrapped, erythrocyte- and liposome-entrapped enzyme in C3H/HeJ Gush mice.

The ability of autologous erythrocytes and liposomes to provide nonimmunogenic vesicles which protect entrapped enzyme from immunologic surveillance and initiation of an immune response was assessed in C3H/HeJ Gush mice following repeated administration of these vesicles with and without entrapped enzyme. Erythrocyte-entrapped bovine beta-glucuronidase elicited no antibody response detectable by double diffusion, passive hemagglutination, complement-dependent lysis, or time-course experiments. Moreover, erythrocyte entrapment protected the enzyme from circulating antibody in mice previously sensitized with unentrapped enzyme. In contrast, repeated IV injection of negatively-charged liposomes loaded with enzyme induced both humoral and cellular responses. Low levels of antibody to the bovine enzyme were detectable by the double antibody technique; no antibodies to the liposome were detectable by complement lysis. In time-course experiments, significant decreases in tissue recoveries of liposome-entrapped beta-glucuronidase were observed in mice sensitized with enzyme-loaded liposomes compared to the recoveries in unsensitized mice, due in part to the rapid degradation of antigen-antibody complexes. A similarly decreased tissue recovery of liposome-entrapped enzyme was apparent in mice with circulating anti-beta-glucuronidase antibody, indicating the inability of liposomes to protect entrapped protein from immunologic surveillance. The cellular response to the liposome vesicle was characterized by the enhanced phagocytic activity of reticuloendothelial cells in the liver and spleen, and the activation of peritoneal macrophages. These results identify erythrocytes as nonimmunogenic carriers capable of protecting entrapped protein from immunologic surveillance and therefore suitable for enzyme replacement endeavors. However, the demonstration that both buffer- and enzyme-loaded liposomes induce an immune response mandates further investigation of these carriers prior to clinical trials of liposome-entrapped therapeutic agents.

Animals↗
PubMed1988

A protocol for the successful long-term enzyme replacement therapy of scurvy in guinea pigs.

Gulonolactone oxidase, a key enzyme in the biosynthesis of ascorbic acid, is missing from guinea pigs and certain other scurvy-prone species. Weekly intraperitoneal injections of glutaraldehyde cross-linked immunoprecipitates of this enzyme have been shown to provide guinea pigs with the capability of synthesizing their own ascorbic acid and of surviving without an exogenous source of this vitamin. This protocol, however, was successful in only a small percentage of the animals tested. The reasons for the limited therapeutic success were investigated. Apparently, the gulonolactone oxidase-treated guinea pigs fed without ascorbic acid were receiving insufficient nutrition. By supplementing these enzyme-treated animals with vitamins A, B, D and E and selenium, we successfully maintained a high proportion of guinea pigs fed without vitamin C.

Animals↗
PubMed1993

Enzyme replacement therapy of infantile Gaucher disease.

We report our experience from enzyme infusion therapy in a girl with infantile (type 2) Gaucher disease. When treatment was started at 5.5 months of age, she already had severe neurological symptoms. After three months of treatment, the hematological parameters and blood glucosylceramide levels were normalized. The spleen and liver sizes were reduced and the neurological deterioration seemed to have stopped. There was, however, no improvement of her existing neurological symptoms. Her lung function deteriorated because of constant aspirations. Enzyme treatment was stopped after seven months. We cannot recommend enzyme substitution therapy when severe neurological signs have already emerged.

Female↗
PubMed1985

Pancreatic enzyme replacement therapy: comparative effects of conventional and enteric-coated microspheric pancreatin and acid-stable fungal enzyme preparations on steatorrhoea in chronic pancreatitis.

The therapeutic effectiveness of a conventional (Pankreon-Granulat) and an acid-protected (Kreon) porcine pancreatic enzyme preparation, and an acid-stable fungal enzyme preparation (Nortase) in the treatment of severe pancreatogenic steatorrhoea was investigated. The study comprised 17 patients with chronic pancreatitis and exocrine pancreatic insufficiency with (A) or without (B) a previous Whipple's procedure (B II resection + partial duodenopancreatectomy). With all three enzyme preparations, a significant (p less than 0.05) reduction in the total faecal fat excretion/day was achieved. In therapy group A, this reduction was, on average, 58% for Kreon (100,000 U lipase/day), 67% for Pankreon-Granulat (360,000 U lipase/day) and 54% for Nortase (75,000 U lipase/day), the respective figures for therapy group B being 58%, 52% and 46% at identical dosages. Thus, in both groups, the effect produced by the conventional porcine pancreatic enzyme preparation and the acid-protected porcine or the acid-stable fungal enzyme preparation was largely equivalent, although the latter two preparations were administered at only 1/4 of the dosages of the former preparation. On the basis of the respective average reduction in total faecal fat excretion and average number of stools/day, it would appear that in patients with chronic pancreatitis and prior Whipple's procedure, Pankreon-Granulat should be administered for enzyme replacement while in patients with an intact upper gastrointestinal tract, Kreon should be administered, in the treatment of steatorrhoea in chronic pancreatitis.

Amylases↗
PubMed2003

Enzyme replacement therapy reduces Gaucher cell burden but may accelerate osteopenia in patients with type I disease - a histological study.

Enzyme replacement treatment (ERT) is effective in controlling the clinical and biochemical manifestation of type I Gaucher disease. Little is known on the evolution of bone marrow histology caused by ERT. We compared the pretreatment trephine bone marrow biopsies in five patients (F32, F41, F50, M55, and M46) with the control biopsies performed after 26-32 months of imiglucerase treatment. The planimetric estimates revealed significant decrease in Gaucher cell burden in all the patients. The post-ERT values ranged from 24% to 65% of the initial total volumes occupied by the Gaucher cells. This resulted mainly from disappearance of Gaucher cells, and to a lesser extent from their shrinkage. Normal hemopoiesis was markedly increased in four of five patients, fat tissue in all the five patients. Surprisingly, the estimated volumes of trabecular bone in the control biopsies were significantly smaller than in the pre-ERT trephines (0.61%, 0.64%, 0.64%, 0.97%, and 0.22% of the initial volumes, P = 0.043). The bone loss correlated rather with the degree of reconstitution of normal hemopoiesis than with the decrease in the Gaucher cell burden. The histological response did not correlate strictly with initial clinical parameters and the genotype, with different reactions to ERT in two sibs (cases 3 and 4). Particularly, ERT alleviated bone manifestations in all four patients with previous bone pains or fractures. ERT may accelerate progress of osteopenia in men and premenopausal women. The clinical significance of this phenomenon remains to be established. Its mechanism may be linked to increased osteolytic activity exerted directly or indirectly by regenerating hemopoietic cells.

Adult↗
PubMed1993

Lysosomal storage diseases: mechanisms of enzyme replacement therapy.

Lysosomal diseases result from deficiency of one of the many enzymes involved in the normal, step-wise breakdown of macromolecules. Studies in vitro have shown that cells from enzyme-deficient patients can be corrected by an exogenous supply of the missing enzyme. This occurs by receptor-mediated endocytosis of normal enzyme added to tissue culture medium and also by direct transfer from normal leukocytes during cell-to-cell contact. Immunohistochemical analysis has revealed that these processes have similar pathways of intracellular transport of the acquired enzymes, which ultimately reach mature lysosomes in the recipient cells. Moreover, recent studies suggest that both mechanisms are important in the therapy of lysosomal storage diseases by bone marrow transplantation. Advances in gene technology are likely to improve the successful treatment of these disorders, by facilitating the large scale production of clinically effective proteins and also by enabling the stable and safe introduction of normal lysosomal genes into cells of affected patients.

Bone Marrow Transplantation↗
PubMed2006

Restricted upper extremity range of motion in mucopolysaccharidosis type I: no response to one year of enzyme replacement therapy.

BACKGROUND: Mucopolysaccharidosis type I (MPS I) results from deficiency of the lysosomal enzyme alpha-L: -iduronidase (IDUA). Glycosaminoglycans (GAGs) accumulate in multiple organs and the storage in connective tissues results in restricted mobility. Previous studies provided evidence of an improvement in range of motion (ROM), as measured by goniometry, after supplementation of recombinant enzyme (ERT). AIM: The aim of the study was to evaluate the efficacy of ERT in improving ROM in patients with MPS I, using a blinded three-dimensional (3D) video analysis of unrestricted movements of the upper extremities. METHODS: In 6 patients with the attenuated phenotype of MPS I, the longitudinal changes in the upper extremity ROM were analysed by 3D video analysis during one year of ERT. RESULTS: At baseline, all studied movements except for elbow flexion were restricted. No significant improvement of the restricted upper extremity ROM was observed after one year of ERT. CONCLUSION: Long-standing restrictions in ROM probably cannot be reversed by ERT. Early initiation of treatment might be essential to prevent irreversible functional defects.

Child↗
PubMed1989

Enzyme replacement therapy in porphyrias--V. In vivo correction of delta-aminolaevulinate dehydratase defective in erythrocytes in lead intoxicated animals by enzyme-loaded red blood cell ghosts.

Resealed erythrocyte ghosts are potential in vivo carriers of exogenous therapeutic enzymes. In the present work, the effect of administering delta-aminolaevulinate dehydratase (ALA-D) encapsulated in autologous red blood cell ghosts (RBCg) to lead intoxicated and normal mice was investigated. Administration of ALA-D loaded RBCg to intoxicated mice produced an immediate and permanent recovery in erythrocytic ALA-D activity; the effect was also noticeable in liver and spleen and absent in kidney, indicating that the entrapped enzyme was significantly stabilized to allow retention of activity in both circulating and phagocytized cells. Administration of ALA-D loaded ghosts to normal mice did not produce significant changes in ALA-D activity in blood, liver, spleen or kidney. Administration of free exogenous enzyme or blood transfusion during lead intoxication was also ineffective; spontaneous recovery of the poisoned animals was very slow. We show that circulating as well as phagocytized ALA-D entrapped in autologous erythrocyte ghosts can be safe and beneficial in the treatment of lead poisoning. Clinical trial in patients is recommended.

Animals↗