title: Carboxyfluorescein as a fluorescent probe for cytoplasmic effects of lymphocyte stimulation.
abstract: The application of carboxyfluorescein (CF), as an impermeable fluorescent probe for lymphocyte stimulation with phytohaemagglutinin (PHA), is investigated by following a decrease in the degree of fluorescence polarization. Since CF does not enter the mitochondria, the present results indicate that the measured effect of stimulation occurs in the cytoplasm. The results also reveal that the fluorescence yield of intracellular CF is smaller than that of extracellular CF. Moreover, the degree of fluorescence polarization of intracellular CF is inversely related to its concentration. Following cell disruption, fluorescence intensity increases and polarization decreases. These effects might indicate a weak or reversible association of intracellular CF with cytoplasmic proteins.
authors.affiliation: Jeromne Schottenstein Cellscan Center for Early Detection of Cancer, Department of Physics, Bar-Ilan University, Ramat-Gan, Israel.
authors.forename: M
authors.initials: M
authors.lastname: Cohen-Kashi
authors.forename: M
authors.initials: M
authors.lastname: Deutsch
authors.forename: R
authors.initials: R
authors.lastname: Tirosh
authors.forename: H
authors.initials: H
authors.lastname: Rachmani
authors.forename: A
authors.initials: A
authors.lastname: Weinreb
mesh_terms: D003593:Cytoplasm / Q000276:immunology / Q000378:metabolism; D005452:Fluoresceins; D005454:Fluorescence Polarization / Q000379:methods; D005456:Fluorescent Dyes; D006801:Humans; D066298:In Vitro Techniques; D008213:Lymphocyte Activation / Q000502:physiology*; D008214:Lymphocytes / Q000276:immunology / Q000378:metabolism; D010835:Phytohemagglutinins / Q000494:pharmacology; D013194:Staining and Labeling / Q000379:methods
chemical_list: D005452:Fluoresceins; D005456:Fluorescent Dyes; D010835:Phytohemagglutinins; C024098:6-carboxyfluorescein