Elastase (human leucocytes)

Elastase is white or light gray crystalline powder. It is soluble in water, stable at ph4-10.5 and 20C, and can be stored for 3-12 months at 60C. Compound elastase is a white ointment containing elastase and Neomycin sulfate.

Elastase is a proteolytic enzyme. It is a member of the subgroup named, peptidyl peptide hydrolases. It is a major anatomic constituent of arteries. It is mainly found in the pancreas and pancreatic juice of various birds and mammals. It is also present in human serum, granulocytes and erythrocytes.

De-fire, wash fat, dry fresh or frozen pork pancreas, put it in a meat grinder and comb, add 3 times the amount of acetone cooled to below 00C, dehydrate it at about 00C under constant stirring for 1h, and centrifuge (recycling waste acetone), Separate the precipitate, add 3 times the amount of cold acetone to the wet cake, and perform the same operation as above. The wet cake is dried in a vacuum drying oven and crushed to obtain dry acetone powder. Keep tightly closed at low temperature for later use. Crushing pig pancreas with acetone (cold) → dehydration; degreasing; dry acetone powder extraction Take dry acetone powder and add a certain amount of water according to the weight of acetone powder to make the weight-volume ratio 5%, and extract for 2h at 20～250C under constant stirring. A small amount of talc powder is added during the filtration of the extract to aid the filtration below 200C, and the clarified extract is obtained by natural filtration with cotton cloth or plate and frame filtration. Acetone powder water: 200C→the extraction extract adsorption The extract is diluted to 2 to 3 times with a certain amount of distilled water, and added to Amberlite CG-50 resin m (raw material) equilibrated with ph6.4 phosphate buffer (0.1mol/L) ): m (resin)=1: 2. Under constant stirring, absorb at 20～25C for 2h, collect the resin, rinse the resin with distilled water until the eluate is colorless, and get the adsorbate. Extraction solution Amberliet CG-50 resin → elution of adsorbents. Add 1.5 times ph9.3 ammonium chloride buffer (0.5mol/L) to each part of adsorption resin. Under constant stirring, elute for 1 hour, separate the resin, and wash After removing the liquid, adjust the pH to neutral with acetic acid (2mol/L) and filter to obtain a clear eluent. Adsorbent ph9.3 buffer → eluent eluent is precipitated at -50C, while stirring, add 3 times the acetone that has been cooled to -50C to the eluent, continue to stir for 10 minutes, and let stand at -50C for several hours. The eluent is acetone; -50C→precipitation precipitation dehydration, drying to collect the precipitate, washing with acetone 3 times, then washing 3 times with ether, and vacuum drying to obtain the original elastase powder. Precipitating acetone; ether→dehydration; drying the original elastase powder

Used to regulate blood lipids

Elastase from human leukocytes has been used:to measure serum elastase activityin proteolytic digestion of fibronectin and salivary glandsin neutrophil elastase (NE) activity assaycell-free NE digestion of E-cadherinscratch wound assayin a study that determined that fragments of Nle3-angiotensin(1-7) accelerate healing in dermal modelsElastase has been used to digest fibronectin. The results were compared with fibronectin digestion by crude human leukocyte homogenate to examine the presence of fibronectin peptides in saliva of patients with Sjgren′s syndrome. It has also been used as a reference to determine the elastase activity in cell lysates. This study examined the effect of all-trans retinoic acid on procoagulant and fibrinolytic activities of cultured blast cells. These blast cells were from patients with acute promyelocytic leukemia.