Purified resting human PMNs do not express either granzyme A or B. (A) Fluorescence-activated cell sorter (FACS) blots (forward scatter [FSC] vs side scatter [SSC]) and cytospin analyses of purified human PBMCs and PMNs. Each fraction was determined to be more than 95% purified as determined by FACS analysis using lineage-specific markers and by microscopic evaluation of cytospins (May-Grünwald/Giemsa; original magnification, ×200). Lymphocyte (lymphs), monocyte (monos), and PMN populations based upon forward and light scatter are indicated. The images were taken using a Nikon Microphot-SA microscope; 20× bright-field objective lens, original magnification ×200; Cytoseal XYL mounting media (Richard-Allan Scientific, Kalamazoo, MI); and analysis camera (×10 magnification) and acquisition software from Soft Imaging System (Lakewood, CA). (B) FACS analysis of purified PBMCs and PMNs for granzyme A and B expression against lineage-specific surface markers. Gates used in FACS analysis for lymphocytes and PMNs are indicated in panel A. (C) FACS analysis of purified PMNs for expression of neutrophil elastase (NE) and cathepsin G (CG). Data shown is representative of 4 independent donor samples. Percentages of total cells for each quadrant are indicated in the upper right corner of each subpanel.