Secreted protein that acts as a key regulator of lysosomal function and as a growth factor involved in inflammation, wound healing and cell proliferation (PubMed:
28541286, PubMed:
28073925, PubMed:
18378771, PubMed:
28453791, PubMed:
12526812). Regulates protein trafficking to lysosomes and, also the activity of lysosomal enzymes (PubMed:
28453791, PubMed:
28541286). Facilitates also the acidification of lysosomes, causing degradation of mature CTSD by CTSB (PubMed:
28073925). In addition, functions as wound-related growth factor that acts directly on dermal fibroblasts and endothelial cells to promote division, migration and the formation of capillary-like tubule structures (By similarity). Also promotes epithelial cell proliferation by blocking TNF-mediated neutrophil activation preventing release of oxidants and proteases (PubMed:
12526812). Moreover, modulates inflammation in neurons by preserving neurons survival, axonal outgrowth and neuronal integrity (PubMed:
18378771).