Title: Proteome array identification of bioactive soluble proteins/peptides in matrigel; relevance to stem cell responses Authors
Submitted to: Cytotechnology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: April 3, 2014
Publication Date: N/A
Interpretive Summary: Matrigel is a biological matrix extracted from the continuously propagated Engelbreth-Holm-Swarm (EHS) mouse tumor. It is widely used for the in vitro culture of cells, either as an aid to cell attachment and growth, or as a 3D biological gel in which cells are suspended and grown. The main components of Matrigel are connective tissue proteins, laminin and collagen. However, Matrigel also has small amounts of various other proteins in it, and these proteins may have potent biological effects on cells that are grown in or on Matrigel. The present study describes the assay of Matrigel for the possible presence of 105 different proteins that included proteins that are cell growth stimulators, cell communication factors, and factors that help cells acquire their specialized functions in the body. The results identified over 2 dozen new proteins that had not been previously known to be in Matrigel. The knowledge of the presence of these proteins in Matrigel will help scientist better interpret their results when using Matrigel in cell biology experiments. Since Matrigel is used for assays of cell growth and function in many biomedical/agricultural areas of study, these results will have a wide ranging impact in fields like cancer research, stem cell biology, and tissue engineering.
Technical Abstract: Matrigel and similar commercial products are extracts of the Engelbreth-Holm-Swarm sarcoma that provide a basement-membrane-like attachment factor or gel that is used to grow cells on or in. To ascertain further what proteins may be present in Matrigel, besides its major basement-membrane constituents, an analysis of the expressed liquid of gelled Matrigel was performed using proteome array technology. Among the growth factors/cytokines assayed, high positive signal intensities were found for IGFBP1, IGFBP3, LIF, platelet factor 4, PlGF-2, and VEGF; moderate levels were found for cyr61, IGFBP2, IGFBP6, IL-1ra, and NOV; and low, but detectable, signals occurred for aFGF, IL-13, IL-23, M-CSF, and VEGF-B. Among the chemokines assayed, high positive signal intensities were found for MIG and serpin E1; moderate levels were found for IP-10, MCP-1, and MCP-5, and low, but detectable, signals occurred for CXCL16, I-TAC, and MIP-1a. Among the other biologically active proteins assayed, high positive signal intensities were found for adiponectin, C5a, endocan, lipocalin-2, sICAM-1, MMP-3, and TIMP-1; moderate levels were found for C-reactive protein, coagulation factor III, endoglin, endostatin/collagen XVIII, endothelin-1, ICAM-1, MMP-9, osteopontin, pentraxin-3, and RANTES; and low, but detectable, signals occurred for fetuin A, MMP-8, pentraxin-2, RBP4, resistin, and TIMP-4. The study identified several new growth factors, chemokines, and biologically active proteins that may have numerous and important effects on cells grown on or in Matrigel.