Measurement of Major Allergen Mus m 1 in Commercial Mouse Allergen Extracts and Mouse Urine

Mus m 1 is a major allergen found in mouse urine and has been shown to contribute to asthma prevalence in inner city homes. Commercially available mouse epithelium extracts are non-standardized. Our goal is to develop monoclonal-antibody-based sandwich ELISA assays for measurement of Mus m 1. Monoclonal antibodies were generated in rats by immunizing with natural Mus m 1 using a proprietary MonoExpress immunization protocol (GenScript USA). Anti-Mus m 1 polyclonal sera were generated in rabbits hyperimmunized with Mus m 1: rabbits were primed subcutaneously with 100 mcg of nMus m 1 in Freund’s Complete Adjuvant, followed by boosts of 100 mcg nMus m 1 in Freund’s Incomplete Adjuvant at weeks 3 and 7. Hybridoma supernatants and polyclonal sera were screened against nMus m 1 and mouse urine. Two sandwich ELISAs (sELISAs) were developed: one in which both the capture (12B10) and detection (biotinylated 11G6) antibodies were monoclonal, and one in which the detection antibody was rabbit polyclonal sera. The monoclonal assay was found to be highly specific and sensitive, and mouse urine contained 3.0 g/L of the antigen, but Mus m 1 in commercial extracts was below the limit of detection. Using polyclonal rabbit sera for detection, the assay was more sensitive. With this assay the Mus m 1 content of mouse urine was 6.7x10-1 g/L and the commercial extracts contained 1.5x10-4 to 2.5x10-3 g/L. sELISA assays has been developed for determining Mus m 1 contents of non-standardized mouse allergen extracts.