Immunoprecipitation and immunoblot blot analysis of plasma L-selectin levels from the ADAM17^ΔZn/ΔZn- and ADAM17^+/+-chimeric mice. Plasma (approximately 40 μL) from 2 ADAM17^ΔZn/ΔZn- and 2 ADAM17^+/+-chimeric mice were subjected to immunoprecipitation using the L-selectin mAb MEL-14 and then to nonreducing SDS-PAGE and immunoblotting, as described in “Materials and Methods.”