Detection of human elastase isoforms by the ScheBo Pancreatic Elastase 1 Test

Area of Science:

• Biochemistry
• Clinical Diagnostics
• Molecular Biology

Background:

• Fecal pancreatic elastase testing is a key noninvasive method for evaluating exocrine pancreatic function.
• Commercial enzyme-linked immunosorbent assays (ELISA) are widely used, but their precise molecular targets are not fully understood.
• Clarifying the targets of these assays is essential for accurate interpretation of results.

Purpose of the Study:

• To identify the specific human pancreatic elastase isoforms detected by the ScheBo Pancreatic Elastase 1 Stool Test.
• To investigate the impact of naturally occurring genetic variants on the test's performance.

Main Methods:

• Recombinant expression and purification of human pancreatic proteinases.
• Detection of various elastase forms (proelastases, active, autolyzed) using the ScheBo Pancreatic Elastase 1 Stool Test.
• Analysis of common genetic variants in CELA3A and CELA3B.

Main Results:

• The test specifically detects chymotrypsin-like elastases (CELA) 3A and 3B, not CELA2A.
• CELA3B generates a significantly higher ELISA signal than CELA3A.
• Most genetic variants of CELA3A and CELA3B do not affect detection, except for CELA3B W79R.
• Inactive, active, and autolyzed forms are detected equally.

Conclusions:

• The ScheBo Pancreatic Elastase 1 Stool Test is specific for human CELA3A and CELA3B.
• CELA3B accounts for the majority of the detected ELISA signal.
• The test's reliability is largely unaffected by common genetic variations in these elastases.