A novel monoclonal antibody against cannabinoid receptor 1.

The cannabinoid receptor 1 (CBR1) is being widely investigated because of its specific structure and functions compared with other cannabinoid receptors. In this study, we immunized BALB/c mice with synthesized human CBR1 polypeptide and obtained a novel monoclonal antibody (MAb) against human CBR1. Analysis through enzyme-linked immunosorbent assay (ELISA), spot-ELISA, Western blot, and immunohistochemistry revealed that the MAb was specifically against recombinant human CBR1 protein, and its subtype and affinity constant (Kaff) were IgG2b/k and 7.85 × 10(8) M/L, respectively. Using this MAb we found that CBR1 is expressed on HL-7702 cells and lipid tissue, raising the possibility that the CBR1 may take a role in glucose and lipid metabolism. Thus, this antibody might facilitate studies for pathophysiology of diseases associated with glucose and lipid metabolism abnormality.