Role of mast cells in allergic inflammation in the skin

在干细胞因子和白细胞介素6的作用下，从脐带血细胞中培养肥大细胞。肥大细胞蛋白酶免疫细胞化学染色显示所有细胞均含有胰蛋白酶。抗ige能有效刺激肥大细胞释放组胺，且呈剂量依赖性和时间依赖性。钙离子载体A23187也以剂量依赖性、时间依赖性的方式诱导组胺释放。化合物48/80和P物质不能诱导细胞释放组胺。作为研究的下一步，我们研究了紫外线照射对p物质诱导的大鼠腹膜肥大细胞释放组胺的影响。紫外光B （UVB）照射抑制组胺释放呈剂量依赖性，8-甲氧基补骨脂素加长波紫外光（UVA）照射抑制组胺释放呈剂量依赖性。UVB照射和8-甲氧基补骨脂素+ UVA照射通过抑制细胞内钙浓度抑制组胺释放。研究肥大细胞增多症患者的肥大细胞亚型。肥大细胞含有胰蛋白酶和乳糜酶是唯一的类型，在皮肤病变的患者与荨麻疹色素沉着。一例系统性肥大细胞增多症患者的非病变皮肤中，肥大细胞主要含有胰蛋白酶和乳糜酶，而病变皮肤中，肥大细胞主要含有胰蛋白酶（但不含乳糜酶）。全身肥大细胞增多症患者的活检标本不仅来自皮肤，还来自淋巴结、骨髓、支气管、鼻黏膜、胃粘膜，均可见含有胰蛋白酶（而非乳糜酶）的肥大细胞浸润。肥大细胞增多症患者血中组胺、胰蛋白酶、白三烯C4水平升高，尿中甲基组胺、白三烯E4水平升高。

Mast cells were raised from umbilical cord blood cells in the presence of stem cell factor and interleukin 6. Immunocytochemical staining for mast cell proteases revealed that all cells contained tryptase. Anti-IgE effectively stimulated the mast cells to release histamine in a dose-dependent, time-dependent manner. Calcium ionophore A23187 also induced histamine release in a dose-dependent, time-dependent manner. Compund 48/80 and substance P failed to induce histamine release from the cells. As a next step of the study, the effects of ultraviolet light irradiation on substance P-induced histamine release from rat peritoneal mast cells were investigated. Ultraviolet light B (UVB) irradiation inhibited the histamine release in a dose-dependent manner, and 8-methoxypsoralen plus long-wave ultraviolet light (UVA) irradiation inhibited in a dose-dependent manner of UVA.UVB irradiation and 8-methoxypsoralen plus UVA irradiation inhibited the histamine release through the suppression of intracellular calcium concentrations.Mast cell subtype of patients with mastocytosis was investigated. Mast cells containing tryptase and chymase were the only type seen in the skin lesions of a patient with urticaria pigmentosa. Mast cells containing tryptase and chymase were predominant in the nonlesional skin of a patient with indolent systemic mastocytosis, however mast cells containingtryptase (but not chymase) were predominant in the lesional skin of the patient. Biopsy specimens from not only the skin but also the lymphnode, bone marrow, bronchus, nasal mucosa, gastric mucosa showed infiltrations of mast cells containing tryptase (but not chymase) in a patient with systemic mastocytosis. Blood levels of histamine, tryptase, leukotriene C4 and urine levels of methylhistamine, leukotriene E4 were elevated in the patients with mastocytosis.