Recombinant DNase

Dornase alfa (Pulmozyme ) is a recombinant human (rh) DNase that selectively cleaves extracellular deoxyribonucleic acid (DNA). This DNA is released during neutrophil degradation and contributes to the high viscosity of CF sputum. Nebulization of dornase alfa 2.5 mg once or twice daily improves daily pulmonary symptoms and function, reduces pulmonary exacerbations, and improves quality of life.16 N-acetylcysteine and hypertonic saline are other mucolytic agents that are occasionally used however, they are not preferred agents due to a greater incidence of bronchospasm and unpleasant odor and taste.5... 

Recombinant DNase preparations have been used in the treatment of cystic fibrosis since the end of 1993. This genetic disorder is common, particularly in ethnic groups of northern European extraction, where the frequency of occurrence can be as high as 1 in 2500 live births. A higher than average incidence has also been recorded in southern Europe, as well as in some Jewish and African-American populations. 

The advent of genetic engineering and improvements in chromatographic methodology facilitated the production of highly purified recombinant human DNase (rhDNase) preparations. Initial in vitro studies proved encouraging incubation of the enzyme with sputum derived from a cystic... 

Actin-binding proteins ABP-50, purification, 196, 78 ABP-120, purification, 196, 79 ABP-240 purification, 196, 76 effect on actin depolymerization, 215, 74 extraction, 196, 311 isolation from Dictyostelium discoideum, 196, 70 platelet-derived actin binding proteins [characterization, 215, 58 purification, 215, 58, 64 recombination with actin, 215, 73] 30-kDa Dictyostelium discoideum actin-crosslinking protein [assays, 196, 91 preparation, 196, 84] actin-depolymerizing factor [assay, 196, 132[ DNase assay, 196, 136 platelet-derived a-actinin [characterization, 215, 58 purification, 215, 58, 70 recombination with actin, 215, 73]. 

Because plasma protein and tissue binding influences the amount of drug in each body compartment, the volume of distribution of a drug may be dose dependent (nonhnear). A limited number of binding sites may result in capacity-limited binding in plasma or tissues. Transport from the blood may also be capacity limited. Examples of dose-dependent volume changes show that the volume of distribution of recombinant human tumor necrosis factor (TNF) alpha decreases sharply with a fourfold increase in dose and that the volume of distribution of recombinant human DNase,... 

A small number of biopharmaceuticals are delivered by nonparenteral means. Recombinant DNase is given by inhalation aerosol to reduce the viscosity of mucus in the lungs of patients with cystic hbrosis. A platelet-derived growth factor in the form of a gel is administered topically for wound healing. Several hormones and peptides are administered in solution by the intranasal route. A solution of an antisense drug used for the treatment of cytomegalovirus retinitis is injected directly into the eye. 

Retention of viscous purulent secretions, which contain high concentrations of extracellular DNA—released by degenerating leukocytes that accumulate in response to infection [24]—in the airways contributes both to reduced pulmonary function and to exacerbations of infection [24,25], Digestion of DNA polymers in purulent secretion with DNAse (dornase-a or Pulmozyme) has been shown to reduce sputum viscosity in cystic fibrosis patients. The availability of recombinant DNAse has allowed its use in an aerosol formulation to deliver the enzyme into the deep lung alveoli of CF patients. The purihed glycoprotein contains 260 amino acids with an approximate molecular weight of 37,000 daltons [26], The primary amino-acid sequence is identical to that of the... 

Shak, S., D.J. Capon, R. Hellmiss, S.A. Marsters, and C.L. Baker, Recombinant human DNase I reduces the viscosity of cystic fibrosis sputum. Proc Natl Acad Sci USA, 1990. 87(23) 9188-92. 

Fuchs, H.J., D.S. Borowitz, D.H. Christiansen, E.M. Morris, M.L. Nash, B.W. Ramsey, B.J. Rosenstein, A.L. Smith, and M.E. Wohl, Effect of aerosolized recombinant human DNase on exacerbations of respiratory symptoms and on pulmonary function in patients with cystic fibrosis. The Pulmozyme Study Group. N Engl J Med, 1994. 331(10) 637 2. 

DNAse, dornase alfa, human recombinant deosyribonucelase I (rhDNAse), produced in CHO cells... 

Mucolytics Pulmozyme (Genentech) Dornase alfa (recombinant human deoxyribonuclease DNAse) In 2.5 mL ampoules Preservative-free. With 0.15mg/mL calcium chloride dihydrate and 8.77mg/mL sodium chloride... 

A particularly interesting feature of the ATP-dependent DNase is its possible involvement in genetic recombination. Thus, certain recombination deficient strains of E. coli with the recB and recC phenotypes (15) appear to lack this enzyme. 

Concerning the biological role of acid DNase, it has been suggested by several authors that this enzyme might be involved in some essential biological mechanism, like DNA replication, where it might play some accessory role, and DNA recombination. If, however, one considers that lysosomes appear to contain all enzymes needed to degrade nucleic acids to nucleosides (Table IV), it seems more likely that, at least under... 

A perfect correlation would be indicated if all the points lay on a 45° line the actual results point towards sufficient correlation. The five best mutants in the broken-line circle were selected to be subjected to DNA recombination, the sexual PCR (Stemmer, 1994a). The method is depicted in Figure 11.9. Genes are pooled in the test tube and split with DNAse at random positions. After electrophoresis... 

There is no cure for SLE. Guillermo el al. (G16) found only 10 randomized controlled trials during the past 5 years, 5 for lupus nephritis and 5 for all SLE patients. Compared to conventional therapies for lupus nephritis, a monthly bolus with intravenous cyclophosphamide is more effective than a monthly bolus with methyl prednisolone, but has significant side effects (including amenorrhea, cervical dysplasia, avascular necrosis, and herpes zoster) in both groups (G14). In order to avoid these side effects, more recent therapies have been developed. However, neither plasmapheresis (Wl), intravenous immunoglobulin (B21), recombinant human DNase (rhDNase) (D3), nor mycophenolate mofetil (C14) was shown to be more effective than conventional therapy. However, some of these... 

D3. Davis, J. C. J., Manzi, S., Yarboro, C., Rairie, J., Mcinnes, I., etal., Recombinant human DNase I (rhDNase) in patients with lupus nephritis. Lupus 8, 68—76 (1999). 

Figure 7.6. Schematic representation of in vitro synthesis of RNA. Shown is a plasmid molecule containing a cloned DNA that is flanked by T3 and T7 promoter sequences. The recombinant plasmid DNA is linearized in such a way that the transcription from one of the promoter elements generates RNA molecules corresponding to the cloned insert DNA and not the plasmid vector DNA. At the end of the reaction plasmid DNA is removed after enzymatic digestion with DNase I, and the pure RNA species is ethanol precipitated.

Bovine pancreatic DNase I was purified in 1945 [3], and it was the first DNase to be crystallized [4]. Until the availability of recombinant hrenun DNase (rUDNase) in the late 1980s [5], bovine pancreas remained the principal source of DNase 1, for biochemical as well as for clinical investigations. 

In a recent publication Linsrdou et al. studied the sole of recombinant DNase I in cancer therapy [86], They showed that recombinant DNase I is an attractive candidate far tumor targeting since it is normally nontoxic but highly... 

P. L. Shah,. P. Scott, R. A. Knight, C. Marriott, C. Rnnasiidia, and M. E, Hodson. In vivo effects of recombinant human DNase I on sputum in patients with cystic fibrosis. Thorax JJ 119-125 (1996). 

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