Elastases assay

In most of these methods some 10-20 mg of elastin is taken for each tube of the assay the elastase unit is rather large and the assay procedures are expensive in enzyme when they are used to control purification procedures. A much more sensitive method, which measures quantities of elastase of the order of one-hundredth the Banga (1952) unit, was devised by Sbarra et al. (1960). In this assay elastin-agar plates arc used and the method is based on measuring the diameter of the clear zone which is produced by elastase deposited in circular holes cut in the gel. This method of assay is also of particular value in screening microorganisms for the production of elastase. 

AAT can be quantified by all immunochemical methods, with immunoturbidimetry and immunonephelometry the most commonly used methods. Because it constitutes about 90% of the serum inhibition of trypsin or elastase activity against small substrates, such as benzoyl-DL-arginine p-nitroanilide, it can also be semiquantified by the inhibitory capacity of serum for these enzymes however, this assay is not specific for AAT. 

Assays of serum AMY, lipase (LPS), trypsin (TRY), chy-motrypsin (CHY), and elastase 1 (El) are applied to investigation of pancreatic disease. Pancreatic function and pathology are discussed in Chapter 48. 

Carroccio A, Verghi F, Santini B, Lucidi V, lacono G, Cavataio F, et al. Diagnostic accuracy of fecal elastase 1 assay in patients with pancreatic maldigestion or intestinal malabsorption. Dig Dis Sci 2001 46 1335-42. 

Samples were assayed by absorbance at 280 nm, Bradford protein assay(.27), and radial immunodiffusion plates (Helena Laboratories). Alpha-1 antitrypsin was assayed for biological activity by competitive assay with elastase (28). DNA was assayed by the diphenylamlne methods of Burton(29) and Giles and Mvers(30). with modifications due to the presence of PEG and salts (31.). Materials were also assayed by size exclusion chromatography on Superose 6 (Pharmacia FPLC), with peak integration at 280 nm. PEG was assayed by HPLC. 

Assay of the isozymers from L rubellus is based on the enzymic reaction with various substrates. F-T and F-III are thought to represent a chymotrypsin-like and a trypsin-like protease, respectively [24], F-II appears to act as a trypsin-like protease or an elastase. Interestingly, F-II1-1 and -2, also with strong caseinolylic activity, have much higher fibrinolytic activity than plasmin as described by Mihara et al. [1,3]... 

From the anti-inflammatory, antipyretic, analgesic, and antioxidant extract of Kageneckia oblonga, Delporte et al. [13] isolated two cucurbitacins which were assayed as potential antioxidants and also as inhibitors of enzymes implicated in inflammatory reactions. Isolated compounds, 23,24-dihydrocucurbitacin F and 3P-( 3-D-glucosyloxy)-16a,23a-epoxy-cucurbitan-5,24-diene-ll-one, Fig. (11), inhibited the production of superoxide anion as well as elastase release in stimulated human neutrophils. In addition, the compounds inhibited both nitrite and... 

Schneider, A., B. Funk, W. Caspary, and J. Stein. 2005. Monoclonal versus polyclonal ELISA for assessment of fecal elastase concentration Pitfalls of a new assay. Clinical Chemistry 51 1052-1054. 

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