Active site (3); Alternative sequence (3); Beta strand (17); Chain (1); Disulfide bond (6); Domain (1); Glycosylation (1); Helix (5); Mass spectrometry (1); Natural variant (1); Propeptide (1); Signal peptide (1); Site (1); Turn (4); By spinal cord injury. This effect is particularly prominent in macrophages, microglia and reactive astrocytes. {ECO:0000269|PubMed:16987227}.; In fluids, highest levels found in milk of lactating women followed by cerebrospinal fluid, nipple aspirate fluid and breast cyst fluid. Also found in serum, seminal plasma and some amniotic fluids and breast tumor cytosolic extracts. Not detected in urine. At the tissue level, highest concentrations found in glandular tissues such as salivary glands followed by lung, colon, fallopian tube, placenta, breast, pituitary and kidney. Not detected in skin, spleen, bone, thyroid, heart, ureter, liver, muscle, endometrium, testis, pancreas, seminal vesicle, ovary, adrenals and prostate. In brain, detected in gray matter neurons (at protein level). Colocalizes with pathological inclusions such as Lewy bodies and glial cytoplasmic inclusions. Overexpressed in primary breast tumors but not expressed in metastatic tumors. {ECO:0000269|PubMed:10997858, ECO:0000269|PubMed:11018688, ECO:0000269|PubMed:11668196, ECO:0000269|PubMed:12928483, ECO:0000269|PubMed:16800739}.