Love K S, Lakshmanan R R, Butterfield J H, Fox C C
Department of Medical Microbiology, Ohio State University College of Medicine, Columbus, 43210, USA.
Cell Immunol. 1996 May 25;170(1):85-90. doi: 10.1006/cimm.1996.0137.
The expression of MHC class II molecules by human mast cells has been reported in immunohistochemical surveys of inflammatory conditions, such as in tuberculin hypersensitivity. While these data suggest that human mast cells may act as antigen-presenting cells under inflammatory conditions, the induction of class II antigens on human mast cells has not been examined. In this study, we determined the effects of the inflammatory cytokines IFN-gamma and IL-4 on the expression of class II antigens HLA-DR, -DP, and -DQ by the human mast cell line HMC-1. HMC-1 cells were incubated with or without 1000 U/ml recombinant human IFN-gamma (rhIFN-gamma) and IL-4 (rhIL-4) for 72 hr and analyzed for expression of MHC class II antigens by direct immunofluorescence and flow cytometry. HMC-1 cells expressed significant levels of HLA-DR and moderate levels of HLA-DP and -DQ at baseline and when cultured without exogenous cytokines. Stimulation by rhIFN-gamma for 72 hr significantly increased the levels of HLA-DR and -DP expression but did not affect levels of HLA-DQ. Stimulation by rhIL-4 for 72 hr had minimal effect on expression of class II molecules, but induced a significant difference in levels of ICAM-1 (CD54) expression, indicating that this cytokine is involved instead in the control of certain accessory molecules. Our data showing constitutive expression of MHC class II molecules on HMC-1 cells and upregulation of that expression by rhIFN-gamma suggest that human mast cells function as antigen-presenting cells at sites where inflammatory cytokines are present.
在诸如结核菌素超敏反应等炎症状态的免疫组织化学调查中，已报道人类肥大细胞表达MHC II类分子。虽然这些数据表明人类肥大细胞在炎症条件下可能作为抗原呈递细胞，但尚未研究人类肥大细胞上II类抗原的诱导情况。在本研究中，我们确定了炎症细胞因子IFN-γ和IL-4对人类肥大细胞系HMC-1上II类抗原HLA-DR、-DP和-DQ表达的影响。将HMC-1细胞在有或无1000 U/ml重组人IFN-γ（rhIFN-γ）和IL-4（rhIL-4）的情况下孵育72小时，并通过直接免疫荧光和流式细胞术分析MHC II类抗原的表达。HMC-1细胞在基线时以及在无外源性细胞因子培养时表达显著水平的HLA-DR和中等水平的HLA-DP及-DQ。rhIFN-γ刺激72小时显著增加了HLA-DR和-DP的表达水平，但不影响HLA-DQ的水平。rhIL-4刺激72小时对II类分子的表达影响最小，但诱导了ICAM-1（CD54）表达水平的显著差异，表明该细胞因子反而参与某些辅助分子的调控。我们的数据显示HMC-1细胞上MHC II类分子的组成性表达以及rhIFN-γ对该表达的上调表明，人类肥大细胞在存在炎症细胞因子的部位作为抗原呈递细胞发挥作用。
