The anti-hu IL-8 (HA) antibody has been validated and is recommended when high IL-8 levels are anticipated. The anti-hu IL-8 antibody may be substituted for the recommended anti-hu IL-8 (HA) detection antibody in order to reduce the lower limit of quantitation (LLOQ) (i.e. to increase sensitivity). Since the IL-8 assay was validated using the anti-hu IL-8 (HA) antibody, when anti-hu IL-8 detection antibody is used, verification of assay performance for specific applications is recommended.