With the help of the broad product portfolio of Immundiagnostik AG in the area of leaky gut, statements can be made about both the epithelial and the immunological barrier of the intestine. For the epithelial barrier, primarily the biomarker Zonulin has been established. Increased zonulin concentrations lead to an active but also reversible opening of the tight junctions. Immundiagnostik AG offers zonulin ELISAs for stool as well as for serum (K 5600, K 5601). In contrast to zonulin, the biomarker α1-Antitrypsin is a passive marker for increased intestinal permeability. α1-Antitrypsin is a serum protein and diffuses through openings in the intestinal mucosa into the lumen of the intestine and can thus be detected in stool samples (K 6750, K 6760, K 6752). A combination of the biomarkers zonulin and α1-antitrypsin is recommended, as low zonulin concentrations can be caused by damage in the epithelium. This would lead to a false negative diagnosis. FABP2 is leaked by structurally damaged intestinal epithelial cells and can be detected in blood samples. Therefore, FABP2 is a biomarker for a severe impairment of intestinal permeability with epithelial damage (K 6809). Both sIgA (K 8870, K 8880) and hBD2 (K 6500) provide information about the immunological barrier of the intestine. If sIgA and/or hBD2 concentrations are decreased, the immunological barrier is not functional, which can lead to increased intestinal permeability.
Specimen collection, storage and preparation
The parameters α1-antitrypsin, sIgA and hBD2 can be combined with the IDK® stool sample preparation tubes (SAS) filled with the extraction buffer IDK Extract® (K 6999). No sample weighing is required to obtain a defined sample quantity. When the yellow dip stick is inserted into the stool sample, the ridges at the tip of the stick fill with stool sample. When the dip stick is inserted into the stool sample tube, excess stool is wiped off, resulting in exactly 15 mg of stool entering the tube. The use of the IDK® SAS allows minimal stool contact and saves time and costs. The IDK Extract® extraction buffer included in the stool sample tube allows storage of the stool sample extract for 7 days at -20°C, 2-8°C and room temperature. The system is ready-to-use and can be used directly for manual as well as for automated processing.
