title: Ratiometric fluorescence polarization as a cytometric functional parameter: theory and practice.
abstract: The use of ratiometric fluorescence polarization (RFP) as a functional parameter in monitoring cellular activation is suggested, based on the physical phenomenon of fluorescence polarization dependency on emission wavelengths in multiple (at least binary) solutions. The theoretical basis of this dependency is thoroughly discussed and examined via simulation. For simulation, aimed to imitate a fluorophore-stained cell, real values of the fluorescence spectrum and polarization of different single fluorophore solutions were used. The simulation as well as the experimentally obtained values of RFP indicated the high sensitivity of this measure. Finally, the RFP parameter was utilized as a cytometric measure in three exemplary cellular bioassays. In the first, the apoptotic effect of oxLDL in a human Jurkat FDA-stained T cell line was monitored by RFP. In the second, the interaction between cell surface membrane receptors of human T lymphocyte cells was monitored by RFP measurements as a complementary means to the fluorescence resonance energy transfer (FRET) technique. In the third bioassay, cellular thiol level of FDA- and CMFDA-labelled Jurkat T cells was monitored via RFP.
authors.affiliation: The Biophysical Interdisciplinary Jerome Schottenstein Center for the Research and the Technology of the Cellome, Department of Physics, Bar-Ilan University, Ramat-Gan 52900, Israel. rtcellom@mail.biu.ac.il
authors.forename: Yitzhak
authors.initials: Y
authors.lastname: Yishai
authors.forename: Dror
authors.initials: D
authors.lastname: Fixler
authors.forename: Meir
authors.initials: M
authors.lastname: Cohen-Kashi
authors.forename: Naomi
authors.initials: N
authors.lastname: Zurgil
authors.forename: Mordechai
authors.initials: M
authors.lastname: Deutsch
mesh_terms: D003198:Computer Simulation; D005454:Fluorescence Polarization / Q000379:methods*; D006801:Humans; D019044:Image Cytometry / Q000379:methods*; D019169:Jurkat Cells / Q000166:cytology* / Q000378:metabolism*; D008077:Lipoproteins, LDL / Q000378:metabolism*; D008856:Microscopy, Fluorescence / Q000379:methods*; D008954:Models, Biological; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013438:Sulfhydryl Compounds / Q000378:metabolism*
chemical_list: D008077:Lipoproteins, LDL; D013438:Sulfhydryl Compounds; C099252:oxidized low density lipoprotein