In direct ELISAs and Western blots, 40% cross-reactivity with recombinant human (rh) S100A8 is observed and no cross-reactivity with recombinant mouse (rm) S100A4, rmS100A9, rmS100A10, rmS100A11, rhS100B, or rhS100P is observed. Reconstitute at 0.5 mg/mL