ISSN:
1365-2559
Source:
Blackwell Publishing Journal Backfiles 1879-2005
Topics:
Medicine
Notes:
Cell death can be divided into necrosis and apoptosis. In histiocytic necrotizing lymphadenitis (HNL), apoptosis is the main form of cell death. Two molecular mechanisms of T-cell-mediated cytotoxicity, one perforin-based and the other Fas-based, have been demonstrated, and both systems induce apoptosis of the target cells. This study was designed to investigate the Fas and perforin pathways in HNL.〈section xml:id="abs1-2"〉〈title type="main"〉Methods and resultsTwelve cases of HNL were analysed using immunohistochemical staining. The Fas and/or FasL-positive cells, including lymphocytes and histiocytes, were frequently encountered in the necrotizing lesions, however, they were rare in the nonpathological regions. The perforin and/or granzyme-positive cells were also confined in the necrotizing lesions. In double staining, CD8-positive lymphocytes occasionally expressed Fas and/or FasL, and histiocytes also expressed FasL and/or Fas. However, CD4-positive lymphocytes rarely expressed FasL and/or Fas. In a flow cytometric analysis, most of the cytotoxic T-cells, which were recognized by cytolytic granules of TIA-1 and considered to be CD8-positive lymphocytes, expressed FasL and Fas. The perforin-positive lymphocytes also expressed FasL and Fas.〈section xml:id="abs1-3"〉〈title type="main"〉ConclusionIn our previous study, the apoptotic cells were T-cells, especially CD8-positive cells rather than CD4-positive cells. Based on these findings, in Fas and perforin pathways, the CD8-positive cells were considered to be effector and target cells, while histiocytes could possibly be enhancers. As a result, both pathways seemed to induce an abundance of apoptosis and thus induce necrotizing lesions.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1046/j.1365-2559.1998.00532.x
Permalink
