About AZU1
Azurophil granules, specialized lysosomes of the neutrophil, contain at least 10 proteins implicated in the killing of microorganisms. This gene encodes a preproprotein that is proteolytically processed to generate a mature azurophil granule antibiotic protein, with monocyte chemotactic and antimicrobial activity. It is also an important multifunctional inflammatory mediator. This encoded protein is a member of the serine protease gene family but it is not a serine proteinase, because the active site serine and histidine residues are replaced. The genes encoding this protein, neutrophil elastase 2, and proteinase 3 are in a cluster located at chromosome 19pter. All 3 genes are expressed coordinately and their protein products are packaged together into azurophil granules during neutrophil differentiation. [provided by RefSeq, Nov 2015]

About Alexa Fluor 647
Alexa Fluor™ 647 (AF647, Alexa 647) has an excitation peak at 650 nm and an emission peak at 665 nm, and is spectrally similar to Cy®5 (GE Healthcare), iFluor® 647 (ATT Bioquest), and DyLight™ 650 (Thermo Fisher Scientific). Alexa 647 is commonly used for flow cytometry, microscopy, super-resolution microscopy applications. It is very bright, photostable, and pH insensitive, all of which contribute to sensitive detection while using this dye.