Cd112

The acronym CD stands for "Cluster of Differentiation" and refers to groups of cellular surface features that have been classified according to biochemical or functional criteria. The CD classification enables comprehensible transparency in immunohistological and immunological research and diagnostics.

Cluster of Differentiation 112 also known as Nectin-2 is a type I membrane protein that is widely expressed in human tissues including hematopoietic cells.

Nectins consist of a family of Ca2+-independent cell adhesion molecules. This family consists of 4 members, the immunoglobulins:

• Nectin-1
• nectin-2
• Nectin-3
• Nectin-4

These support cell-cell adhesion via their extracellular domain. Furthermore, they act as immune receptors with viral glycoproteins.

Nectins play a role in progression of various carcinomas. CD112 is massively expressed by various carcinoma cells and antigen-presenting cells in the tumor microenvironment. This is the case in breast and ovarian carcinoma.

Together with CD155 (PVR), CD112 (Nectin-2) is a ligand of TIGIT. There is now ample evidence that the TIGIT pathway regulates T cell-mediated and natural killer cell-mediated tumor recognition in vivo and in vitro.

Another ligand for CD112 is DNAM-1(CD226), a cell surface glycoprotein that functions as an adhesion molecule. After communicating with activating receptors, DNAM-1 regulates interferon-γ production against a variety of pathogens via NK cell cytotoxicity (Martinet L et al. 2015).

The proteins involved in all cell adhesions are the Ca2+-dependent cadherins which are linked to the actin cytoskeleton by the various anchoring proteins(catenins, vinculin and alpha-actinin).

1. Martinet L et al (2015) Balancing natural killer cell activation through paired receptors. Nat Rev Immunol 15:243-254.

2. Samanta D et al. (2015) Nectin family of cell-adhesion molecules: structural and molecular aspects of function and specificity. Cell Mol Life Sci 72: 645-658.