Journal: Cells
Article Title: Impaired Intestinal Permeability of Tricellular Tight Junctions in Patients with Irritable Bowel Syndrome with Mixed Bowel Habits (IBS-M)
doi: 10.3390/cells12020236
Figure Lengend Snippet: Immunofluorescence detection of tight junction proteins in IBS-M patients with confocal microscopy and super-resolution microscopy. ( A ) Shown are colonic crypts from a control biopsy and IBS-M biopsy. Tricellulin is stained green, ZO-1 is stained red, and the co-localization of tricellulin and ZO-1 appears yellow (merge). Overall, tricellulin staining in the TJ appears to be attenuated in IBS-M compared to control (red signals predominate in IBS-M). The red circle (right) indicates a sorting out from the tricellular tight junction (tTJ). Distance-intensity plots visualize the de-localization of tricellulin away from tTJs. In control, tricellulin (green) shows defined signal peaks at the tricellular meeting points of the TJ as indicated by the blue arrows (marked are length and direction of the pixel intensity measurement along the TJ). In contrast, the intensity plot in IBS-M shows no peak but rather disseminated signals, indicating redistribution of tricellulin from the tricellular to the bicellular TJ. ( B ) The intensity of tricellulin was measured in the tTJ in relation to the intensity in the bicellular tight junction (bTJ) at a distance of 2 µm from the measuring point in the tTJ. A low-intensity ratio (tTJ/bTJ) indicates that tricellulin is sorted out of the tTJ which was more pronounced in IBS-M patients than in controls (each n = 3 patients; * p < 0.05). ( C ) Super-resolution stimulated emission depletion (STED) microscopy of occludin (red) and tricellulin (green) in patients’ colon mucosa crypts. In controls, tricellulin is restricted to tTJs (bar = 500 nm). In contrast in IBS-M, the tricellulin signal was redistributed into the bTJ. Data represent mean ± SD.
Article Snippet: A STED–compatible cover slide (Carl Zeiss, Jena, Germany) was placed on each slide.
Techniques: Immunofluorescence, Confocal Microscopy, Microscopy, Staining