Polychromatic flow cytometry

A number of methods for the study of apoptosis and necrosis by flow cytometry have been developed (see review by Steensma et al., 2003). Unfortunately, none of the methods are rigorously specific for apoptosis and many show poor overall specificity for cell death or cannot discriminate between the terminal stages of apoptosis and necrosis. Moreover, some of the fluorochromes used to detect apoptosis have emission spectra that fully overlap the spectra of those typically used for immunophenotyping or have a broad emission spectrum that makes compensation in multi- or polychromatic flow cytometry difficult, if not impossible. Thus, the preferred method would be one that measures two aspects of apoptosis, can discriminate between apoptotic and dead cells, and uses fluorochromes that allow simultaneous immunophenotyping. One such method is the annexin-V/7-amino-actinomycin-D assay described by Merchant et al. (2001) that is available in kit from BD Biosystems (San... 

Chattopadhyay PK, Price DA, Harper TF, Betts MR, Yu J, Gostick E, Perfetto SP, Goepfert P, Koup RA, De Rosa SC, Bruchez MP, Roederer M. Quantum dot semiconductor nanocrystals for immunophenotypmg by polychromatic flow cytometry. Nat Med 2006 12 972-977. 

Petrausch U, Haley D, Miller W, Floyd K, Urba WJ, Walker E. Polychromatic flow cytometry a rapid method for the reduction and analysis of complex multiparameter data. Cytometry 2006 69A(12) 1162-1173. 

Another important advantage of polychromatic flow cytometry is the measurement of rare cell populations. Multichannel detections allow applying the so-called dump channel. Undesired cells can be excluded from analysis using this dump channel after their staining by specific antibodies, labeled with the same fluorochromes. Using the other fluorescent channels (dyes), low-frequency cell subsets can be detected in a very sensitive manner. 

Troiano, L. Eerraresi, R. Lugli, E. Nemes, E. Roat, E. Nasi, M. Pinti, M. Cossarizza, A. Multiparametric analysis of cells with different mitochondrial membrane potential during apoptosis by polychromatic flow cytometry. Nat. Protoc. 2007, 2, 2719-2727. 

Grawe J, Nusse M and Adler I-D (1997). Quantitative and qualitative studies of micronucleus induction in mouse erythrocytes using flow cytometry. 1. Measurement of micronucleus induction in peripheral blood polychromatic erythrocytes by chemicals with known or suspected genotoxicity. Mutagenesis, 12, 1-8. 

Lahdetie, J. Grawe, J. (1997) Flow cytometric analysis of micronucleus induction in rat bone marrow polychromatic eiythrocytes by l,2 3,4-diepoxybutane. 3.4-epoxy-l-butene, and 1.2-epoxybutane-3,4-diol. Cytometry, 28, 228-235... 

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