Wiener E, Curelaru Z
J Reticuloendothel Soc. 1975 Jun;17(6):319-32.
Acid hydrolases, among them cathepsins A, B, C, and D, and their intracellular distribution have been studied in mouse peritoneal macrophages, a model commonly used for the study of mononuclear phagocyte functions in host-parasite relationships and in the immune response. Thioglycollate stimulated peritoneal macrophages showed high specific activities of acid hydrolases in compatison to liver and spleen. Fractionation of these macrophages by differential and isopycnic sucrose density centrifugation showed heterogeneous enyzme distribution patterns which were different for the various hydrolases studied. Thus, these enzymes appeared to be associated with particles of varying weight and density and in the different particles the ratios of the various acid hydrolase activities were quite dissimilar. With the majority of hydrolases a portion of the enzyme activity was found in fragile heavy particles of densities higher than 1.25 that sedimented together with the nuclei. Cultured macrophages derived from the non-irrated peritoneum exhibited a less heterogenous distribution pattern for acid phosphatase than did the thioglycollate stimulated cells. The heterogeneity of acid hydrolase distributions in the thioglycollate induced macrophages was attributed to their physiologic state of stimulated endocytosis causing a continuous formation of primary and secondary lysomes. Under certain conditions macrophages might contain lysosome-like particles with cathepsin ratios unfavorable for complete proteolysis. The existence of such particles is suggested as a possible explanation for the persistence of immunogenic protein within these cells.
酸性水解酶，包括组织蛋白酶A、B、C和D，及其在细胞内的分布，已在小鼠腹腔巨噬细胞中进行了研究。小鼠腹腔巨噬细胞是研究宿主-寄生虫关系和免疫反应中单核吞噬细胞功能常用的模型。与肝脏和脾脏相比，经巯基乙酸盐刺激的腹腔巨噬细胞显示出较高的酸性水解酶比活性。通过差速和等密度蔗糖密度离心对这些巨噬细胞进行分级分离，结果显示不同水解酶的酶分布模式存在异质性。因此，这些酶似乎与重量和密度各异的颗粒相关，并且在不同颗粒中，各种酸性水解酶活性的比例差异很大。对于大多数水解酶而言，一部分酶活性存在于密度高于1.25的易碎重颗粒中，这些颗粒与细胞核一起沉降。源自未经刺激的腹膜的培养巨噬细胞，其酸性磷酸酶的分布模式比经巯基乙酸盐刺激的细胞的分布模式异质性更小。巯基乙酸盐诱导的巨噬细胞中酸性水解酶分布的异质性归因于其受刺激的内吞作用的生理状态，导致初级和次级溶酶体不断形成。在某些条件下，巨噬细胞可能含有组织蛋白酶比例不利于完全蛋白水解的溶酶体样颗粒。这些颗粒的存在被认为是这些细胞内免疫原性蛋白质持续存在的一种可能解释。
