LEGEND MAX™ Human Soluble Nogo-B ELISA Kit with Pre-coated Plates 5 Pre-coated Plates

Nogo B belongs to the reticulon family of proteins, characterized by having the reticulon homology domains (RHDs) at the C-termini. The best characterized member of the reticulon family is RTN4, which has three isoforms: Nogo-A, the largest among the three isoforms, with full length human protein consisting of 1192 aa and a calculated molecular weight of 135 kD; Nogo B, an intermediate form with 373 aa and a molecular weight of ~37 kD, and a shorter form, Nogo-C, with 199 aa, a molecular weight of ~25 kD, and a very small N-terminal region. Nogo-B is a spliced variant of Nogo-A, while Nogo-C uses an alternative promoter and unique exon to encode its short amino terminus. Nogo A and Nogo B share an identical N-terminal region (aa 1-185), while this region is absent in Nogo C.

Nogo-A is primarily expressed in the central nervous system and is identified as a potent inhibitor of axonal growth and repair. Nogo-C exists mainly in neurons and skeletal muscle. Although Nogo-B is expressed ubiquitously, the highest expression is found in endothelial cells, vascular smooth muscle cells and inflammatory cells.

It has been shown that Nogo B plays an essential role in vascular remodeling and appears to be important in angiogenesis and metabolic processes. Interestingly, the amino terminus of Nogo B (amNogo B) can be a soluble peptide (soluble Nogo B or sNogo B) that promotes vascular adhesion and migration of endothelial cells by binding to the Nogo B receptor (NgBR). Recently, it was shown that cells exhibiting the strongest expression of NgBR include activated CD4+ and CD8+ T cells and, therefore, soluble Nogo B may play a role in modulating T cell activation.

Based on sequence homology, this ELISA kit will not detect human Nogo C, but will detect full-length or N-terminus (aa 1-185) of human Nogo A. However, Nogo A is a membrane-bound protein and there is no soluble form in biological samples. Therefore, this kit specifically quantitaes the human soluble Nogo B from cell culture supernatant, serum, plasma and other biological fluids. It is analytically validated with ready-to-use reagents.