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Updated: May 15, 2026

Quantification of Immunostained Caspase-9 in Retinal Tissue
Published on: July 25, 2022
Possible role of apoptosis in the pathogenesis and clinical evolution of radicular cyst: an immunohistochemical study
C Loreto1, C Galanti, R Leonardi
1Department of Bio-Medical Sciences, Section of Anatomy, University of Catania, Catania, Italy. carla.loreto@unict.it
Aim:
To investigate whether the apoptotic cascade is activated through the extrinsic pathway in epithelial lining and connective tissue of radicular cysts.
Methodology:
Fifteen radicular cysts were fixed in formalin, embedded in paraffin wax and processed for immunohistochemistry to evaluate the expression of polyclonal antibodies against Tumour necrosis factor-related apoptosis-inducing ligand (TRAIL), DR5 and caspase-3. Immunocomplexes were treated with the secondary antibodies and finally detected using the avidin-biotin-peroxidase complex. Immunoreactivity was visualized by development with 3,3'-diaminobenzidine. Data were analysed using the Mann-Whitney U-test; P < 0.05 was considered significant.
Results:
The three antibodies were detected in connective tissue fibroblasts of all radicular cysts; TRAIL and DR5 immunoexpression was significantly greater (P < 0.05) compared with that of caspase-3. The three antibodies were also expressed in almost all epithelial layers and in endothelial cells of newly formed vessels.
Conclusion:
The involvement of apoptosis in the pathogenesis of radicular cysts, demonstrated by the immunoexpression patterns of TRAIL, DR5 and caspase-3 in lining epithelium and connective tissue, may explain their bland clinical aggressiveness and slow, benign evolution.
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