Fig 1: Western blot showing specificity of custom developed antibodies to Rat MCP-2. The custom 3F4.5 mouse monoclonal and the rabbit polyclonal antibody recognize the intact recombinant rat mast cell protease-2 (rMCP-2) protein (A) and do not cross react with rMCP-1 (B), rMCP-4 (C) or purified human chymase. The recombinant rMCP-1, 2 and 4 have a C or N-terminal Myc tag and the left panel illustrates that the recombinant proteins run at ∼27 kD. The 3F4.5 monoclonal and the rabbit polyclonal antibodies recognize the rMCP-2 protein (A – 2nd and 3rd panels) but not purified rMCP-1 (B), rMCP-4 (C) or human chymase (hChymase; 2nd and 3rd panels in each row). The R&D mouse monoclonal recognizes CMA1, the purified human chymase, but not the rMCP-1, 2 or 4 proteins (4th panel). As depicted in the far right panel 3F4.5 specifically recognizes rat MCP-2.