Department of Pathology, University Medical Center Utrecht, 3584 CX Utrecht, The Netherlands.
Immunol Rev. 2010 May;235(1):117-27. doi: 10.1111/j.0105-2896.2010.00889.x.
Cytotoxic lymphocytes are armed with granules that are released in the granule-exocytosis pathway to kill tumor cells and virus-infected cells. Cytotoxic granules contain the pore-forming protein perforin and a family of structurally homologues serine proteases called granzymes. While perforin facilitates the entry of granzymes into a target cell, the latter initiate distinct apoptotic routes. Granzymes are also implicated in extracellular functions such as extracellular matrix degradation, immune regulation, and inflammation. The family of human granzymes consists of five members, of which granzyme A and B have been studied most extensively. Recently, elucidation of the specific characteristics of the other three human granzymes H, K, and M, also referred to as orphan granzymes, have started. In this review, we summarize and discuss what is currently known about the biology of the human orphan granzymes.
细胞毒性淋巴细胞装备有颗粒，这些颗粒通过颗粒外排途径被释放出来，以杀死肿瘤细胞和病毒感染的细胞。细胞毒性颗粒包含形成孔的蛋白穿孔素和一组结构同源的丝氨酸蛋白酶，称为颗粒酶。虽然穿孔素有助于颗粒酶进入靶细胞，但后者启动不同的凋亡途径。颗粒酶还涉及细胞外功能，如细胞外基质降解、免疫调节和炎症。人类颗粒酶家族由五个成员组成，其中颗粒酶 A 和 B 研究得最为广泛。最近，也开始阐明另外三个人类颗粒酶 H、K 和 M 的特定特征，这些颗粒酶也被称为孤儿颗粒酶。在这篇综述中，我们总结和讨论了目前已知的关于人类孤儿颗粒酶生物学的知识。
