C5 chemotactic fragments produced by an enzyme in lysosomal granules of neutrophils.
C5 chemotactic fragments produced by an enzyme in lysosomal granules of neutrophils.
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DOI：
10.4049/jimmunol.104.3.535
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发表时间：
1970-03
影响因子：
4.4
通讯作者：
Peter A. Ward;Jeffrey H. Hill
中科院分区：
文献类型：
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作者：
Peter A. Ward;Jeffrey H. Hill
来自兔中性粒细胞的溶酶体颗粒含有一种酶，可以将人类补体(C5)的第五组分裂解成具有化学活性的片段。根据孵育条件的不同，该酶将C5裂解成不同分子量的化学活性片段，而不是补体的第三组分。一个片段在超速离心和凝胶过滤中的行为与参考标准细胞色素c相似。溶酶体颗粒裂解物和C5相互作用产生的趋化活性的量是C5和裂解物浓度以及孵育时间的函数。中性粒细胞溶酶体颗粒的C5裂解酶的最适pH为中性。根据凝胶过滤，它的估计分子量为35,000，被含有碱性氨基酸的酯抑制，对ε-氨基己酸的抑制敏感，并在不同程度上对大豆胰蛋白酶抑制剂和乙二胺四乙酸乙二酯的作用敏感。中性粒细胞中存在一种能够将C5裂解成具有化学活性的片段的酶，这可能反映了一旦急性炎症过程正在进行，中性粒细胞就有可能以非免疫方式加剧急性炎症过程。
Lysosomal granules from rabbit neutrophilic leukocytes contain an enzyme that cleaves the fifth component of human complement (C5) into chemotactically active fragments. The enzyme cleaves C5, but not the third component of complement, into chemotactically active fragments of variable molecular weights, depending upon conditions of incubation. One fragment consistently behaves in ultracentrifugation and gel filtration similar to the reference standard cytochrome c. The amount of chemotactic activity generated by interaction of the lysosomal granule lysate and C5 is a function of concentrations of C5 and lysate, as well as duration of incubation. The C5-cleaving enzyme of neutrophil lysosomal granules has a neutral pH optimum for activity. Based upon gel filtration, it has an estimated molecular weight of 35,000, is inhibited by esters bearing basic amino acids, is susceptible to inhibition by ε-amino caproic acid and in varying degree is susceptible to action of soybean trypsin inhibitor and EDTA. The presence in the neutrophil of an enzyme capable of cleaving C5 into chemotactically active fragments may reflect the potential for the neutrophil to exacerbate in a non-immunologic manner the acute inflammatory process once it is underway.