The MMPs/TIMP and mast cells evaluation of the periapical granulomas

Introduction: The periapical granulomas are a response for host protective ability against the pathogens of infected dental pulp. The effect is a stimulation and a migration of the immunocompetent cells into the inflammatory lesions. The chronic immunosuppressive therapy after the organ transplantation has influence on the proliferation process and on the stimulation number of the cell types of an immunosuppressive system. Objectives: The microscopic evaluation of the periapical granulomas of patients after organ transplantation, with immunosuppression. Methods: The tissues samples of the periapical granulomas were taken after extraction, from 15 patients with immunosuppression and from 15 patients without immunosuppression. In the microscopic assessment of periapical granulomas we estimated: 1. the structure and cellular using haematoxylin and eosin stainig, 2. the organization of collagen network using Syrius Red staining, 3. mast cell infiltration toluidyne blue stainig 4.expression of enzymes: metalloproteinases- 1,-2,-3 and their tissues inhibitor (TIMP-1) using immunohistochemical stainig. Results: The evaluation of the microscopic picture showed that: the formation of structure of periapical lesions is less regular; there are many more fibrous components and less frequent inflammatory infiltration cells in immunosuppression. It was found that in the examined group of patients there is an increased number of mast cells and a decreased reactivity of tissues to immunohistochemical stainig for metalloproteinases. Conclusions: The obtained results showed the difference in the course of the inflammatory processes, in the immunocompromised patients it is a consequence of immunosuppression. Less frequency of the inflammatory cells and a lower expression of MMPs proved also, that there is an important suppression of the response to an inflammatory factor in the patients with the immunosuppression. The mast cells are the autonomic population of cells less sensitive to the lymphocytic agents like the immunosuppressive therapy, and/or the degradation of the mast cells are inhibited by immunosuppression.