Rapid method for improving slide quality in the bone marrow micronucleus assay; an adapted cellulose column procedure

Micronuclei are routinely scored in anucleate erythrocytes in bone marrow s mears stained with acridine orange. Intense fluorescence from the many nucl eated cells in the preparations can interfere with micronucleus detection a nd cause fatigue in the reader. A method for removing nucleated cells by fi ltering bone marrow through cellulose packed in syringes was developed by R omagna some ten years ago, but has not been used routinely because of the e xcessive time needed to prepare columns. We have modified the method very s imply by filling chromatography columns by pipet with a cellulose suspensio n. We show here that column filtration of bone marrow does not affect the n umbers of micronucleated polychromatic erythrocytes (MN-PCEs) scored from m ice treated with the chromosome breaking agents mitomycin C and cyclophosph amide, or the aneuploidy-inducing spindle poisons, colchicine and vinblasti ne. The extra preparation time is only about half an hour for a full scale micronucleus assay, and results in better slides and faster scoring. (C) 19 99 Elsevier Science B.V. All rights reserved.