Rat Anti-Mouse Panendothelial Cell Antigen Clone MECA-32 mAb

Monoclonals were produced using mouse lymph-node stromal cells as the immunizing antigen. Rat IgG2a antibody from hybridoma was purified from cell culture supernatant by Protein G chromatography. The MECA-32 antibody reacts with a dimer of 50-55ñkDa subunits expressed on most or all endothelial cells in the embryonic and adult mouse, with the exception of cardiac and skeletal muscle and the brain. Recent reports have shown that the antigen is the Plasmalemma vesicle-associated protein (also named Plasmalemma vesicle protein-1, PV-1 or MECA-32 antigen), a type II membrane protein. It is a membrane-associated protein of caveolae and is found in fenestral and stomatal diaphragms in fenestrated endothelia and transendothelial channels. Normally in skeletal and cardiac muscle, MECA-32 antigen expression is limited to small arterioles and venules, however, under conditions of inflammation, it can be induced on previously non-expressing vessels in cardiac muscle. In the central nervous system (CNS), the panendothelial cell antigen expression is developmentally regulated. During embryonic development, the antigen is found on brain vasculature up to day 16 of gestation, after which it disappears. The cessation of MECA-32 antigen expression in the CNS may be associated with the establishment of the blood-brain barrier, which begins on day 16 of gestation. In the adult mouse, inflammation in the CNS can lead to re-expression of the panendothelial cell antigen.

Protein G chromatography.

The MECA-32 antibody reacts with the iPlasmalemma vesicle-associated proteini, a dimer of 50-55 kDa subunits expressed on most or all endothelial cells surfaces in the embryonic and adult mouse, with the exception of cardiac and skeletal muscle and the brain.