rhCEACAM-20 Fc, CF (50 UG)

Background: CEACAM-20

Carcinoembryonic antigen-related cell adhesion molecule-20 (CEACAM-20) is a member of the CEACAM subfamily of glycoproteins in the immunoglobulin (Ig) superfamily. Mature human CEACAM-20 consists of a 420 aa extracellular domain, a 21 aa helical transmembrane, and a 114 aa cytoplasmic domain. The extracellular domain possesses four IgC2-like domains, which are stabilized by disulfide bonds, as well as several predicted glycosylation sites (1-5). The extracellular domain of CEACAM-20 is also unique among the CEACAMs because it contains a truncated IgV-like N domain (2). The extracellular domain of human CEACAM-20 has 64% and 62% aa identity to the mouse and rat protein, respectively. Also, the cytoplasmic domain is unusually long compared to most other CEACAMs and is predicted to contain four tyrosine phosphorylation sites, two of which correspond to the immune-receptor tyrosine-based activation motif (ITAM) (2, 3). Human CEACAM proteins have been linked to numerous intercellular-adhesion and intracellular signaling processes including cell adhesion, growth, and recognition, differentiation, angiogenesis, and apoptosis (7, 8). Human CEACAM-20 expression is limited to the reproductive system and the intestinal tract, with the highest levels of expression found in the small intestine and prostate (2, 3). An in vitro model of human prostate morphogenesis showed that CEACAM-20 is co-expressed with CEACAM-1 and plays a critical role in the formation of prostate organoids, making it a marker for prostate cancer (2). Although the exact mechanism is not fully understood, CEACAM-20 may promote the proliferation of intestinal epithelial cells (IECs) (9). There is evidence suggesting CEACAM-20 can induce the production of chemokines like interleukin (IL)-8 and stimulate inflammatory responses in colitis and Crohn's disease (6). CEACAM-20 is also thought be act as a physiological substrate for SAP-1 in the intestinal epithelium (10).