Rothenberg M E, Austen K F
Department of Medicine, Harvard Medical School, Boston, Massachusetts 02115.
Ann N Y Acad Sci. 1989;556:233-44. doi: 10.1111/j.1749-6632.1989.tb22506.x.
The structure of the proteoglycan synthesized by rodent mast cells has been a useful biochemical marker of mast cell subpopulations, since mucosal mast cells synthesize predominantly oversulfated chondroitin sulfate proteoglycan and connective tissue mast cells synthesize heparin proteoglycan. Mast cells are intimately associated with fibroblasts in tissues and fibroblasts maintain the connective tissue type mast cell ex vivo. Whereas mouse IL-3-dependent, immature mast cells synthesize predominantly chondroitin sulfate E proteoglycan, after coculture with fibroblasts, the proliferating mast cells (cloned or uncloned) synthesize heparin proteoglycans, as well as change their phenotype to resemble connective tissue mast cells. Although there is a single peptide core for both heparin and chondroitin sulfate secretory granule proteoglycans, the relative predominance of a specific glycosaminoglycan is determined by the microenvironment in which the cell resides. This microenvironment can regulate the phenotypic properties of mast cells including the expression of their cationic constituents such as neutral proteases and the structure of their anionic proteoglycans.
啮齿动物肥大细胞合成的蛋白聚糖结构一直是肥大细胞亚群有用的生化标志物，因为黏膜肥大细胞主要合成过度硫酸化的硫酸软骨素蛋白聚糖，而结缔组织肥大细胞合成肝素蛋白聚糖。肥大细胞在组织中与成纤维细胞密切相关，并且成纤维细胞在体外维持结缔组织型肥大细胞。虽然小鼠白细胞介素-3依赖的未成熟肥大细胞主要合成硫酸软骨素E蛋白聚糖，但与成纤维细胞共培养后，增殖的肥大细胞（克隆的或未克隆的）合成肝素蛋白聚糖，并改变其表型以类似于结缔组织肥大细胞。虽然肝素和硫酸软骨素分泌颗粒蛋白聚糖有单一的肽核心，但特定糖胺聚糖的相对优势由细胞所处的微环境决定。这种微环境可以调节肥大细胞的表型特性，包括其阳离子成分如中性蛋白酶的表达及其阴离子蛋白聚糖的结构。
