Immunolocalization of bone-resorptive cytokines in rat pulp and periapical lesions following surgical pulp exposure
This study was undertaken to directly quantify the cell types that produce bone-resorptive cytokines Interleukin 1-IL-1a, IL-B, tumor necrosis factor-TNFa and TNFB in infected pulps and periapical tissues, following pulp exposure in the rat model system.
In periapical lesions, a local immune response can be studied. Within this milieu are inflammatory cells, i.e., T and B cells, macrophages, and plasma cells; and noninflammatory cells, i.e., fibroblasts, endothelium, osteoblasts, and osteoclasts. Since TNF and interleukins are known to mediate bone resorption, it would be of interest to see which cells are active in releasing this mediator.
This study utilizes a rat model in which root exposure to oral bacteria was created. By using immuno-histochemistry the authors were able to show that within several days cells express bone-resorptive cytokines with TNFa and IL-1a being expressed by day two. The primary cytokine-releasing cells were the macrophages and fibroblasts, with occasional staining of neutrophils, osteoblasts, and osteoclasts. [D.H.]
Tani-ishii N., C. Wang and P. Stashenko, Oral Microbiol Immunol, 10:213, 1994