Rapid screening for deficiency of alpha 1-proteinase inhibitor.
This rapid screening procedure for detection of low but functional elastase-inhibitory activity in human plasma is based on the fact that incubation of excess porcine pancreatic elastase (EC 3.4.21.36) with plasma results in formation of a complex with active alpha 1-proteinase inhibitor (alpha 1PI, also called alpha 1-antitrypsin). In normal individuals all of the elastase is complexed, leaving no free enzyme to hydrolyze the elastase substrate, and the reaction mixture remains clear. Because individuals homozygous for the Z allele have relatively low concentrations of alpha 1PI, their plasma cannot complex all of the elastase in the assay. The uncomplexed enzyme hydrolyzes the elastase-specific p-nitroanilide substrate, producing a yellow reaction mixture. Use of this simple assay for early screening of individuals for alpha 1PI deficiency may substantially decrease the number of untreated cases of familial emphysema, a disorder that develops as a result of a genetically derived proteinase-proteinase inhibitor imbalance.
Lloyd
C
C
Athens Research and Technology, Inc., GA 30604.
Travis
J
J
D000510:Alpha-Globulins / Q000097:blood; D004198:Disease Susceptibility; D004646:Emphysema / Q000235:genetics*; D005838:Genotype; D006720:Homozygote; D006801:Humans; D006868:Hydrolysis; D007122:Immunoelectrophoresis; D019272:Leukocyte Elastase; D008403:Mass Screening / Q000379:methods; D008744:Methylamines; D010196:Pancreatic Elastase / Q000097:blood / Q000378:metabolism; D000515:alpha 1-Antitrypsin / Q000097:blood / Q000235:genetics / Q000378:metabolism; D019896:alpha 1-Antitrypsin Deficiency
D000510:Alpha-Globulins; D008744:Methylamines; D000515:alpha 1-Antitrypsin; C037741:alpha 1-antitrypsin-leukocyte elastase complex; C025500:alpha(2)-microglobulin; D010196:Pancreatic Elastase; D019272:Leukocyte Elastase