General description
>200 kDa observed. Variable depending on levels of glycosylation.
The monoclonal antibody (mAb) Das-1 was originally desiganted as clone 7E12H12 and was thought to target a 40 kDa colon-specific tropomyosin (TM) isoform or a TM-related protein. It was later found that this clone specifically immunoprecipitated a high molecular weight chaperone protein that targets tropomyosin 5 (TM5) in human colon epithelial cells and subsequently named Colon Epithelial Protein (CEP). The Das-1 target is a glycoprotein with variable apparent sizes depending on the level of glycosylation. The target glycoprotein immunoprecipitated from the plasma membrane of DLD-1 colon cancer cells appears with an apparent molecular size of 185 kDa, while the target isolated from LS-180 colon cancer cells migrates with a size range extends to greater than 200 kDa. Das-1/CEP immunoreactivity is reported to be associated with Barrett′s metaplasia, Barrett′s adenocarcinoma, as well as with gastric adenocarcinomas and carcinoma-associated intestinal metaplasia, but no reactivity has been found in normal esophageal, gastric or small intestinal mucosa. When tested by ELISA and imunoblotting against recombinant human tropomyosins isoforms 1-5, none of five hTM isoforms reacted with mAB DAS-1. As determined by immunofluorescence and FACS analyses, CEP/Das-1 immunoreactivity is detected in several colon cancer lines (DLD-1, LS180, T84), but not in the colorectal adenocarcinoma cell line HT-29. CEP/Das-1 immunoreactivity is not detected among non-colonic epithelial cell lines (293-T, HeLa, pancreatic cancer) or hematopoietic lines (K562, KGI, Daudi).
Immunogen
Human colonic protein extract.
Application
Anti-CEP Antibody, clone Das-1 (7E12H12) is an antibody against CEP for use in Immunohistochemistry (Paraffin), Western Blotting, Immunoprecipitation, ELISA, Dot Blot.
Western Blotting Analysis: Prior to the production of Cat. No. MABC530 by ion-exchange chromatography, the CEP immunoreactivity of the ascites was determined by Western blotting against ulcerative colitis (UC) tissue homogenates, LS-180 colon adenocarcinoma cell lysates, LS180 culture supernatant, and purified CEP (Courtesy of Dr. Kiron M. Das, UMDNJ-Robert Wood Johnson Medical School, New Jersey).
Western Blotting Analysis: A representative lot detected elevated CEP (colon epithial specific protein) levels among intraductal papillary mucinous neoplasm (IPMN) patients samples with high-risk/malignant lesions (Das, K.K., et al. (2014). Gut. 63(10):1626-1634).
Western Blotting Analysis: A representative lot detected CEP in colon adenocarcinoma cell line LS180 and in isolated colon epithelial cells, as well as in LS-180 culture supernatant, but not in normal jejunal epithelial cells (Kesari, K.V., et al. (1999). Clin. Exp. Immunol. 118(2):219-227).
Immunoprecipitation Analysis: A representative lot co-immuoprecipitated tropomyosin 5 with CEP from the culture supernatant of human adenocarcinoma cell line LS180 (Kesari, K.V., et al. (1999). Clin. Exp. Immunol. 118(2):219-227).
ELISA Analysis: A representative lot was used as the capture antibody in combination with the isotype switched mAb Das-1 IgG as the detection antibody using purified CEP and cyst fluid samples from Intraductal papillary mucinous neoplasm (IPMN) patients (Das, K.K., et al. (2014). Gut. 63(10):1626-1634).
Immunohistochemistry Analysis: A representative lot detected significantly higher CEP (colon epithial specific protein) immunoreactivity among intraductal papillary mucinous neoplasm (IPMN) patients samples with high-risk/malignant lesions (Das, K.K., et al. (2014). Gut. 63(10):1626-1634).
Immunohistochemistry Analysis: Representative lots detected CEP (colon epithial specific protein) immunoreactivity by both fluorescent and non-fluorescent immunhistochemistry in colonic, but not small intestinal, enterocytes using both frozen and formalin-fixed, paraffin-embedded tissue sections (Moriichi, K., et al. (2009). Int. J. Cancer. 124(6):1263-1269; Piazuelo, M.B., et al. (2004). Mod. Pathol. 17(1):62-74; MIrza, Z.K., et al. (2003). Gut. 52(6):807-812; Glickman, (2001). J.N., et al. Am J Surg Pathol. 25(1):87-94; Griffel, L.H., et al. (2000). Dig. Dis. Sci. 45(1):40-48; Hamilton, M.I., et al. (1995). Clin. Exp. Immunol. 99(3):404-411; Halstensen, T. S., et al. (1993). Gut. 34(5):650-657; Das, K.M., et al. (1987). J. Immunol. Vol. 139(1):77-84).
Dot Blot Analysis: A representative lot detected CEP immunoreactivity in colon protein extracts (Hamilton, M.I., et al. (1995). Clin. Exp. Immunol. 99(3):404-411).
Biochem/physiol Actions
Clone 7E12H12 (mAb DAS-1) specifically reacts with Colon Epithelial Protein (CEP), but not human tropomyosins isoforms (hTM1-5). CEP/Das-1 immunoreactivity is detected in several colon cancer lines (DLD-1, LS180, T84), but not in the colorectal adenocarcinoma cell line HT-29. CEP/Das-1 immunoreactivity is not detected among non-colonic epithelial cell lines (293-T, HeLa, HUVEC, pancreatic cancer) or hematopoietic lines (K562, KGI, Daudi).
Physical form
Format: Purified
Analysis Note
Evaluated by Immunohistochemistry in human colon tissue.
Immunohistochemistry Analysis: A 1:1,000 dilution of this antibody detected CEP in human colon tissue.
Other Notes
Concentration: Please refer to lot specific datasheet.
