Subcellular distribution of proteins recognized by antibody AHN-17. Primary granules, secondary granules, plasma membranes, and cytosol were isolated from the neutrophils by nitrogen cavitation and differential centrifugation and were suspended in extraction buffer. The antigens recognized by antibody AHN-17 were isolated from each fraction by affinity chromatography with ANH-17 and were analyzed by SDS-PAGE in a 10% gel under non-reducing (lanes A-D) and reducing conditions (lanes E-H). The amount of antigen applied to each lane was adjusted to represent the same percentage of starting material. Primary granules are shown in lanes A and E, secondary granules in lanes B and F, plasma membranes in lanes C and G, and cytosol in lanes D and H. Gels were stained with coomassie blue.