Ueki A, Yamaguchi M, Ueki H, Watanabe Y, Ohsawa G, Kinugawa K, Kawakami Y, Hyodoh F
Department of Hygiene, Kawasaki Medical School, Kurashiki, Japan.
Immunology. 1994 Jun;82(2):332-5.
Silica (SiO2) or related substances such as silicone ([-R2Si-O-]n), which is used in plastic surgery, or asbestos (e.g. chrysotile; 3MgO.2SiO2.H2O) have 'adjuvant effects'. In a study of scleroderma patients in Germany more than 78% had experienced exposure to silicate dust. T-cell receptor (TcR) V beta gene analysis on CD4- CD8- double-negative alpha beta T cells from scleroderma patients, using polymerase chain reaction (PCR), showed that certain V beta genes, V beta 5, V beta 7 and V beta 17, were predominantly expressed in the cells. We found that certain V beta repertoires, V beta 5.3 and V beta 6.7, were predominantly expressed on fractionated T cells with a high Ca2+ level that had been stimulated by chrysotile in vitro. The intracellular Ca2+ level in human peripheral blood mononuclear cells (PBMC) increased after incubation with silica or chrysotile. Interleukin-2 (IL-2) release from PMBC also rose significantly with chrysotile stimulation, but no change was observed when major histocompatibility complex (MHC) class II DP/DR positive cells were depleted. Therefore, our results support the possibility that silicate acts as a superantigen.
二氧化硅（SiO₂）或相关物质，如用于整形手术的硅酮（[-R₂Si-O-]ₙ），或石棉（如温石棉；3MgO·2SiO₂·H₂O）具有“佐剂效应”。在德国一项针对硬皮病患者的研究中，超过78%的患者曾接触过硅酸盐粉尘。利用聚合酶链反应（PCR）对硬皮病患者的CD4⁻CD8⁻双阴性αβT细胞进行T细胞受体（TcR）Vβ基因分析，结果显示某些Vβ基因，即Vβ5、Vβ7和Vβ17，在这些细胞中占主导表达。我们发现某些Vβ谱系，Vβ5.3和Vβ6.7，在体外经温石棉刺激后，在高Ca²⁺水平的分离T细胞上占主导表达。人外周血单个核细胞（PBMC）与二氧化硅或温石棉孵育后，细胞内Ca²⁺水平升高。经温石棉刺激后，PBMC释放的白细胞介素-2（IL-2）也显著增加，但当主要组织相容性复合体（MHC）II类DP/DR阳性细胞被清除时，未观察到变化。因此，我们的结果支持硅酸盐作为超抗原的可能性。
