Each lot of this antibody is quality control tested by immunofluorescent staining with flow cytometric analysis. Test size products are transitioning from 20 µl to 5 µl per test. Please check your vial or your CoA to find the suggested use of this reagent per million cells in 100 µl staining volume or per 100 µl of whole blood. It is recommended that the reagent be titrated for optimal performance for each application. Read more at www.biolegend.com/testsize regarding the test size change.

MPO staining procedure:

1. Prepare cells of interest, perform cell surface antigen staining as described in BioLegend’s Cell Surface Immunofluorescence Staining Protocol, then fix cells in 1.0 ml/tube Fixation Buffer (Part No.78078) in the dark for 20 minutes at room temperature.
2. Centrifuge at 350 x g for 5 minutes, discard supernatant.
3. Dilute 10X Permeabilization Wash Buffer (Cat. No. 421002) to 1X in DI water.
4. Resuspend fixed cells in 1.0 ml/tube Permeabilization Wash Buffer and centrifuge at 350 x g for 5-10 minutes.
5. Repeat step 4 twice.
6. Resuspend fixed/permeabilized cells in the approximate 50-100 µl residual Permeabilization Wash Buffer and add 20 µl FITC-conjugated MPO antibody (Part No.78079) or mouse IgG1,κ isotype control (Part No.78080). Incubate for 30 minutes in the dark at room temperature.
7. Wash 2x with 1.0 ml of Permeabilization Wash Buffer and centrifuge at 350 x g for 5 minutes.
8. Resuspend the cells in 0.5 ml Cell Staining Buffer and interrogate by flow cytometry using proper machine settings.

Materials Provided in this kit:
1. Anti-human MPO FITC, Part No. 78079, 50 tests
2. Mouse IgG1 isotype control FITC, Part No. 78080, 50 tests
3. Fixation Buffer, Part No. 78078, 50 ml
4. Permeabilization buffer, Cat. No. 421002, 100 ml