Vimentin (VIM) is an intermediate filament component of the cytoskeleton of mesenchymal cells. It is important for maintaining cell integrity and shape. Vimentin also regulates cell migration via cytoskeletal rearrangements and is involved in regulating autophagy. In immunohistochemistry, it is positive in the cytoplasm of cells of mesenchymal origin, such as lymphocytes, endothelial cells, astrocytes, epidermal Langerhans cells, macrophages, and interstitial stromal cells. In cancer, it is positive in lymphomas and stromal tumors and is helpful for identifying melanomas, schwannomas and tumors of mesenchymal origin. References: Am J Surg Pathol. 2011;35:1722, PMID: 21997693; F1000Res. 2018 Nov 15;7. pii: F1000 Faculty Rev-1796, PMID: 30505430; PLoS One. 2019 Jan 30;14(1):e0209665, PMID: 30699149; Toxicol Pathol. 2010 Jan;38(1):131-41, PMID: 20028992