Exocytosis of tertiary granule lumen proteins

Tertiary (gelatinase) granules are part of a continuum of peroxidase-negative granules formed in myelocytes, metamyelocytes, band cells and segmented neutrophils. They differ from secondary granules by having a low content of antimicrobial substances, and are more readily exocytosed (Sengelov et al. 1995). Tertiary granules are primarily a reservoir of extracellular matrix degrading enzymes and membrane receptors that are needed for neutrophil extravasation and diapedesis (Faurschou & Borregaard 2003).三级（胶元酶）颗粒是构成在髓细胞、成熟髓细胞、带状细胞和分叶中性粒细胞中形成的过氧化物酶阴性颗粒连续体的一部分。它们与次级颗粒的区别在于含有较少的抗菌物质，并且更容易发生胞吐作用（Sengelov 等人，1995 年）。三级颗粒主要作为细胞外基质降解酶和膜受体的储存库，这些酶和受体对于中性粒细胞的渗出和游走至关重要（Faurschou 与 Borregaard，2003 年）。