An Artificial Intelligence-Based Digital Analysis of Immunolocalization of MMP2 and TIMP2 in the Jejunum of Rats Treated with Calcineurin Inhibitors.

(1) Background: The main goal of this study was to analyze the morphology of the rat's jejunum after long-term treatment with calcineurin inhibitor-based immunosuppressive drugs and to investigate their impact on the location of MMP-2 and its inhibitor TIMP-2, as well as the balance between them. (2) Methods: Twenty-four rats were divided into four groups receiving different immunosuppressive regiments. After six months of treatment, the jejunums were collected and analyzed. (3) Results: immunosuppressive drug panels containing calcineurin inhibitors (CNIs) have a negative impact on the morphology and morphometry of the small intestinal wall. These drugs disrupt the MMP-2/TIMP-2 balance. Both CsA and TAC interfere with the synthesis of intercellular matrix components in the connective tissue of the small intestine. Furthermore, tacrolimus appears to disrupt the MMP-2/TIMP-2 balance in the small intestine the most, as the results show the highest difference between MMP-2 and TIMP-2 expression. The results were also confirmed by digital analysis of tissue segmentation. (4) Conclusions: The research conducted in this study is unique because there is limited information available on the direct effects of immunosuppressive drugs on the expression of MMP-2 and their inhibitors in the jejunum. Additionally, this study involves three drugs instead of one, which accurately reflects the panel of drugs used in organ recipients. Our results suggest that immunosuppressive drugs affect morphology and MMP2/TIMP2 immunoexpression; however, further studies are required. AI-based tools provide a reliable analysis of tissue samples, which represents an exciting approach for future histopathological studies. However, the results of the analyses generated by these tools need to be verified by specialists.