An immunoelectron-microscopic study of class II major-histocompatibility complex molecule-expressing macrophages and dendritic cells in experimental rat periapical lesions
An immunoelectron-microscopic study of class II major-histocompatibility complex molecule-expressing macrophages and dendritic cells in experimental rat periapical lesions
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DOI：
10.1016/s0003-9969(01)00031-0
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发表时间：
2001-08-01
影响因子：
3
通讯作者：
Takagi, M
中科院分区：
文献类型：
--
作者：
Kaneko, T;Okiji, T;Takagi, M
以往的研究表明，异质群体的第二类主要组织相容性复合物（MHC）分子表达的非淋巴样细胞，超微结构分类为巨噬细胞和树突状细胞（DC）细胞样细胞，包括主要的免疫细胞群体在实验性根尖周病变在大鼠磨牙。在这项研究中，这两种类型的细胞的相对比例的时间变化进行了检查，假设他们参与病变的发病机制的不同方面。在5周龄Wistar大鼠的下颌第一磨牙中通过手术牙髓暴露来诱导损伤。观察期设定为0（正常）、3、14、28和56天。根据超微结构将对OX 6免疫反应（对II类MHC分子反应）的非淋巴样细胞分类为巨噬细胞和DC细胞样细胞，并在每个时间点评估两种类型细胞的频率。ED 1（对几乎所有巨噬细胞和DC反应）也用于鉴定巨噬细胞和DC细胞样细胞。在第3天，根尖周组织中的大多数OX 6+细胞和ED 1+细胞具有新募集的巨噬细胞的超微结构外观。第14天，当病变扩展活跃时，OX 6+巨噬细胞明显多于OX 6 + DC细胞样细胞（P < 0.01）。然而，在28天时，当病变扩展停止时，DC细胞样细胞的数量显著超过OX 6+巨噬细胞（P < 0.01），这在56天时保持恒定。OX 6+非淋巴细胞和OX 6-淋巴细胞之间的细胞与细胞接触，表明功能性相互作用，最常见于28天时。这些结果支持的概念，即II类MHC分子表达的巨噬细胞在最初的病变扩张中发挥一定的作用，并表明，DC细胞样细胞可能主要参与免疫防御永久抗原的挑战后，病变稳定。(C)2001爱思唯尔科技有限公司版权所有。
Previous studies have demonstrated that heterogeneous populations of class II major histocompatibility complex (MHC) molecule-expressing non-lymphoid cells, ultrastructurally classified as macrophages and dendritic cell (DC) cell-like cells, comprise the major immune cell population in experimental periapical lesions in rat molars. In this study, the temporal changes in relative proportions of the two types of cells were examined, on the hypothesis that they are involved in different aspects of the pathogenesis of the lesions. The lesions were induced by making surgical pulp exposures in mandibular first molars of 5-week-old Wistar rats. Observation periods were set at 0 (normal), 3, 14, 28, and 56 days. Non-lymphoid cells immunoreactive to OX6 (reactive to class II MHC molecules) were classified as macrophages and DC cell-like cells according to their ultrastructure, and the frequencies of the two types of cells were assessed at each time-point. ED1 (reactive to nearly all macrophages and DCs) was also used to identify macrophages and DC cell-like cells. At 3 days, most OX6 + cells and ED1 + cells in the periapical tissue had the ultrastructural appearance of newly recruited macrophages. At 14 days, when the lesion was actively expanding, there were significantly more OX6 + macrophages than OX6 + DC cell-like cells (P < 0.01). However, at 28 days, when lesion expansion had ceased, DC cell-like cells significantly outnumbered OX6 + macrophages (P < 0.01), this remained constant at 56 days. Cell-to-cell contact between OX6 + non-lymphoid cells and OX6 - lymphocytes, suggesting a functional interaction, was most frequently seen at 28 days. These results support the notion that class II MHC molecule-expressing macrophages play some part in the initial lesion expansion, and suggest that DC cell-like cells may primarily be involved in immune defence against perpetuated antigenic challenges following lesion stabilization. (C) 2001 Elsevier Science Ltd. All rights reserved.