Immunization of mice with chicken egg albumin (ovalbumin/OVA) in a precipitate complex with aluminum hydroxide (alum) is a highly effective means of inducing a potent TH2-mediated immune response. OVA/alum immunized mice produce anti-OVA antibodies predominantly of the IgG1 and IgE isotypes that mediate tissue-specific effector functions in multiple mouse models of chronic inflammation, including allergic asthma, allergic rhinitis, and cutaneous hypersensitivity. When using one of these models, it is often desirable to measure anti-OVA antibody levels in the plasma or serum to determine the effectiveness of the immunization, the activity of a drug, or the effect of a specific gene deletion. IgG1 is the predominant anti-OVA immunoglobulin isotype found in the serum or plasma of mice immunized with OVA/alum, the plasma concentration of OVA-specific IgG1 is typically 1,000-fold greater than that of OVA-specific IgE. Therefore, the measurement of anti-OVA IgG1 is a commonly used method of assessing the magnitude of this TH2 immune response. Cayman"s Anti-Ovalbumin IgG1 (mouse) ELISA Kit is an immunometric (i.e., "sandwich") assay which can be used to measure anti-ovalbumin of the IgG1 isotype in mouse plasma and serum without prior sample purification. Affinity-purified anti-ovalbumin IgG1 isolated from the plasma of mice immunized with OVA/alum is used as the standard. The standard curve spans the range of 1.56-200 ng/ml, with an LLOQ of 1.56 ng/ml.