Role of macrophages on periodontal destruction in rat experimental periodontitis caused by topical application of lipopolysaccharide

在本研究中，我们试图通过实验阐明巨噬细胞/单核细胞系统在脂多糖（LPS）引起的牙周边缘组织炎症变化中的作用。采用免疫组化方法，对雄性Wistar大鼠牙周边缘组织巨噬细胞动态、IL-1 β等细胞因子合成及破骨细胞和淋巴细胞动态进行了研究。由于本研究是在前人研究项目的基础上进行的，因此，其中的结果用新获得的数据再次报道。因此，1。局部应用LPS一次后，发现牙龈上皮下结缔组织中ED1阳性巨噬细胞和Ia阳性巨噬细胞增多。提示部分巨噬细胞可能产生IL-1β，激活破骨细胞牙槽骨吸收。2. LPS剂量增加后，早期ED1阳性细胞和Ia阳性细胞数量显著增加。推测这些Ia阳性细胞可能参与了病变特异性免疫应答的建立。3. 虽然第一次LPS作用后未检测到Pan T和Pan B细胞，但第二次LPS作用后3小时，结缔组织和腭龈上皮下的Pan T细胞增多。第二次LPS处理后，ED1阳性细胞和Ia阳性树突状细胞数量明显增加，提示这些巨噬细胞大部分转变为Ia阳性细胞，Ia阳性抗原呈递细胞的增加可能诱导了T细胞的出现。综上所述，在体内实验条件下，lps刺激后炎性病变诱导的ED1阳性巨噬细胞可能通过分泌IL-1 β破坏牙槽骨，也可能通过建立免疫应答来保护病变。少

In this research, we tried to elucidate experimentally a role of macrophage/monocyte system on inflammatory changes in marginal periodontal tissue caused by lipopolysaccharide (LPS). The LPS from E. coli were administered once and twice from the molar gingival sulcus of a male Wistar rats, and the dynamics of macrophages in the rat marginal periodontal tissue, synthesis of the cytokines such as IL-1 β and dynamics of the osteoclasts and lymphocytes were investigated using an immunohistochemical method. As this research was done succeeding from the previous research projects, a part. of the results were reported again with the newly obtained data. As a result, 1. After once topical application of LPS, it was revealed that ED1 positive macrophages and Ia positive macrophages increased especially in the subepithelial connective tissue of the gingiva. It was suggested that some of these macrophages might produce IL-1β and activate osteoclastic alveolar bone resorption. 2. Twice application … More of LPS caused remarkable increase of ED1 positive cells and Ia positive cells in an early stage. It was suspected that these Ia positive cells might participate establishment of specific immune response in the lesion. 3. Although Pan T and pan B cells were not detected after once application of LPS, pan T cells increased 3 hours after second application of LPS in the connective tissue under the junctional epithelium and palatal gingival epithelium. As ED1 positive cells and Ia positive dendritic cells markedly increased after second LPS administration, It was suggested that much of these macrophages changed to Ia positive cells and increase of Ia positive antigen presenting cells might have induced appearance of T cell. In conclusion, it was demonstrated under the in vivo experimental condition that ED1 positive macrophages induced in the inflammatory lesion after LPS-stimulation might cause destruction of alveolar bone due to production of IL-1 β, and also might protect the lesion by establishment of immune response. Less