Craig S S, Schechter N M, Schwartz L B
Department of Anatomy, Medical College of Virginia, Virginia Commonwealth University, Richmond.
Lab Invest. 1989 Jan;60(1):147-57.
Mast cells at immature stages of development were identified in human tissues by electron microscopic techniques. General morphologic criteria of immaturity (such as a high apparent nuclear:cytoplasmic ratio and small cell size), the presence of few granules (those present being smaller than those in mature mast cells) and a lack of features of mast cell activation were used together to determine the level of maturity. Mast cells were identified as being of the T or TC type by immunogold staining with polyclonal rabbit IgG anti-chymase and murine monoclonal anti-tryptase primary antibodies and the appropriate gold-labeled secondary antibodies. Only those cells with tryptase-positive granules were recognized as mast cells. Immature T mast cell granules contained the same characteristic discrete scrolls found in their mature counterparts and all stained positive for tryptase. The presence of trace amounts of chymase in a minority of these granules, as in mature T mast cells, could not be ruled out. The majority of granules in immature TC mast cells had one or more amorphous electron-dense cores rather than the grating and lattice substructures characteristic of granules in mature TC mast cells. Secretory granules in immature TC mast cells stained positively for tryptase and chymase. Occasional immature TC mast cells contained a complete granule or a portion of a granule with the substructure characteristic of mature TC mast cells, favoring the concept that these TC mast cell forms are developmentally related. Essentially all mast cells in foreskin of newborns appeared immature, whereas 10, 5, 10, and 15% of the mast cells in adult lung, foreskin, bowel mucosa and bowel submucosa, respectively, appeared immature. The distribution of T and TC types of immature mast cells seemed to parallel that of the mature mast cell types. These compositional and ultrastructural differences between immature T and TC types of mast cells suggest that from the time granule formation begins, and possibly before this time, each type of human mast cell follows a distinct developmental pathway.
通过电子显微镜技术在人体组织中鉴定出处于发育未成熟阶段的肥大细胞。使用未成熟的一般形态学标准（如明显较高的核质比和较小的细胞大小）、少量颗粒的存在（这些颗粒比成熟肥大细胞中的颗粒小）以及缺乏肥大细胞活化特征来共同确定成熟水平。通过用多克隆兔IgG抗糜蛋白酶和鼠单克隆抗组织蛋白酶原抗体以及适当的金标记二抗进行免疫金染色，将肥大细胞鉴定为T型或TC型。只有那些含有组织蛋白酶原阳性颗粒的细胞才被识别为肥大细胞。未成熟T肥大细胞颗粒含有与其成熟对应物中发现的相同特征性离散卷轴，并且所有颗粒组织蛋白酶原染色均为阳性。与成熟T肥大细胞一样，不能排除少数这些颗粒中存在微量糜蛋白酶。未成熟TC肥大细胞中的大多数颗粒具有一个或多个无定形电子致密核心，而不是成熟TC肥大细胞颗粒特有的光栅和晶格亚结构。未成熟TC肥大细胞中的分泌颗粒组织蛋白酶原和糜蛋白酶染色均为阳性。偶尔有未成熟TC肥大细胞含有一个完整的颗粒或具有成熟TC肥大细胞亚结构特征的颗粒部分，这支持了这些TC肥大细胞形式在发育上相关的概念。基本上所有新生儿包皮中的肥大细胞似乎都未成熟，而在成人肺、包皮、肠黏膜和肠黏膜下层中，分别有10%、5%、10%和15%的肥大细胞似乎未成熟。未成熟肥大细胞的T型和TC型分布似乎与成熟肥大细胞类型的分布平行。未成熟T型和TC型肥大细胞之间的这些组成和超微结构差异表明，从颗粒形成开始时，甚至可能在此之前，每种类型的人类肥大细胞都遵循一条独特的发育途径。
