About Cathepsin S
The preproprotein encoded by this gene, a member of the peptidase C1 family, is a lysosomal cysteine proteinase that participates in the degradation of antigenic proteins to peptides for presentation on MHC class II molecules. The mature protein cleaves the invariant chain of MHC class II molecules in endolysosomal compartments and enables the formation of antigen-MHC class II complexes and the proper display of extracellular antigenic peptides by MHC-II. The mature protein also functions as an elastase over a broad pH range. When secreted from cells, this protein can remodel components of the extracellular matrix such as elastin, collagen, and fibronectin. This gene is implicated in the pathology of many inflammatory and autoimmune diseases and, given its elastase activity, plays a significant role in some pulmonary diseases. Alternatively spliced transcript variants encoding distinct isoforms have been found for this gene. [provided by RefSeq, May 2020]

About Alexa Fluor 405
Alexa Fluor™ 405 (AF405, Alexa 405) has an excitation peak at 401 nm and an emission peak at 421 nm and is similar in size, brightness and application to V450 (BD Biosciences), Vio®Blue® (Miltenyi Biotec), Cascade Blue® (ThermoFisher Scientific), Pacific Blue® (ThermoFisher Scientific). Alexa 405 is most commonly used in flow cytometery, and fluorescence microscopy applications.