A protocol to guide development of a sensitive ELISA for canine erythropoietin

Background: The determination of canine erythropoietin (EPO) concentration is crucial for monitoring the effect of human recombinant (hr) EPO therapy in dogs with chronic renal failure. Current assays are not specific for canine EPO and not sensitive enough to detect physiologic EPO levels in dogs. Objective: The objective of this study was to develop a simple and sensitive ELISA for canine EPO that could serve as a starting point for developing a commercially available assay. Methods: The ELISA was based on a mouse monoclonal antibody (mAb) and a rabbit polyclonal antibody (pAb) using 2 different immunization techniques: gene electrotransfer (GET) to generate the pAb and multiple antigen peptides (MAPs) to generate the mAb. The ELISA was performed using both EPO obtained from HeLa cells transfected with an expression plasmid encoding canine EPO and canine plasma with known concentrations of EPO. Results: The ELISA standard curve was linear for canine EPO concentrations of 7-66 mU/ml. Coefficients of variation were about 10%. No cross-reactivity between canine EPO and hrEPO was detected. Conclusions: Using novel GET and MAP technology, we developed a sensitive and specific ELISA for canine EPO that can be used to guide future clinical applications for EPO detection and monitoring in dogs. (C)2003 American Society for Veterinary Clinical Pathology.