Upon initial thawing, recombinant rat MCP-1 (MN 555110) should be aliquoted into polypropylene microtubes and frozen at -80°C for future use. Alternatively, the product can be diluted in sterile neutral buffer containing not less than 0.5 - 10 mg/mL carrier protein, such as human or bovine albumin, aliquoted and stored at -80°C.For in vitro biological assay use, carrier-protein concentrations of 0.5 - 1 mg/mL are recommended. For use as an ELISA standard, carrier-protein concentrations of 5 - 10 mg/mL are recommended. Failure to add carrier protein or store at indicated temperatures may result in a loss of activity.Carrier proteins should be pre-screened for possible affects in each investigator"s experimental system. Carrier proteins may have an undesired influence on experimental results due to toxicity, high endotoxin levels or possible blocking activity.

ELISA Standard:Recombinant rat MCP-1 (MN 555110) can be useful as a quantitative standard for measuring rat MCP-1 protein levels using sandwich ELISA with the purified C4 antibody (Cat. No. 555072) as a capture antibody and the biotinylated B4 antibody (Cat. No. 555074) as the detection antibody. To obtain linear standard curves, investigators may want to consider using doubling dilutions of recombinant rat MCP-1 from 2000-5 pg/mL to be included for each ELISA plate.For measuring rat MCP-1 in serum or plasma, investigators are highly encouraged to use the BD OptEIA™ Rat MCP-1 Set (Cat. No. 555130).

Bioassay: Investigators are advised that the Bioassay application is not routinely tested for this material and are highly encouraged to both titrate this material and include appropriate controls in relevant experiments.An activity range encompassing an ED50 = 60 - 600 ng/mL has previously been reported using THP-1 as indicator cells utilizing a calcium flux assay.

Ligand Blocking Control for Immunofluorescent Staining of Cytokines:Recombinant rat MCP-1 can be used as a blocking control to demonstrate the specificity of MCP-1 staining by the PE-conjugated format (Cat. No.554443) of the 2H5 Anti-Rat MCP-1 antibody. Investigators are advised that this blocking application is not routinely tested for this material.The use of staining controls for the immunofluorescent staining and flow cytometric analysis of cytokine producing cells has been previously described (Prussin et al.).