Five-parameter fluorescence imaging: wound healing of living Swiss 3T3 cells.
AuthorsDeBiasio R, Bright GR, Ernst LA, Waggoner AS, Taylor DL
JournalJ Cell Biol
PubMed ID2444600
'Cellular functions involve the temporal and spatial interplay of ions, metabolites, macromolecules, and organelles. To define the mechanisms responsible for completing cellular functions, we used methods that can yield both temporal and spatial information on multiple physiological parameters and chemical components in the same cell. We demonstrated that the combined ... More
Intramitochondrial dyes allow selective in vitro photolysis of carcinoma cells.
AuthorsOseroff AR, Ohuoha D, Ara G, McAuliffe D, Foley J, Cincotta L
JournalProc Natl Acad Sci U S A
PubMed ID3467335
'Carcinoma cell mitochondria preferentially accumulate and retain certain cationic dyes to a much greater extent than most normal cells. Thus, they can potentially serve as targets for highly selective photochemotherapy. We evaluated 10 rhodamine and cyanine dyes as carcinoma-specific mitochondrial photosensitizers in vitro. The most effective, N,N''-bis(2-ethyl-1,3-dioxolane)kryptocyanine (EDKC), caused marked, ... More
Differential requirement for caspase 9 in apoptotic pathways in vivo.
AuthorsHakem R, Hakem A, Duncan GS, Henderson JT, Woo M, Soengas MS, Elia A, de la Pompa JL, Kagi D, Khoo W, Potter J, Yoshida R, Kaufman SA, Lowe SW, Penninger JM, Mak TW
JournalCell
PubMed ID9708736
'Mutation of Caspase 9 (Casp9) results in embryonic lethality and defective brain development associated with decreased apoptosis. Casp9-/- embryonic stem cells and embryonic fibroblasts are resistant to several apoptotic stimuli, including UV and gamma irradiation. Casp9-/- thymocytes are also resistant to dexamethasone- and gamma irradiation-induced apoptosis, but are surprisingly sensitive ... More
An oxidative stress-mediated death pathway in irradiated human leukemia cells mapped using multilaser flow cytometry.
AuthorsSheng-Tanner X, Bump EA, Hedley DW
JournalRadiat Res
PubMed ID9840183
'OCI/AML-2 acute myeloid leukemia cells were found to undergo apoptosis after treatment with y rays from a 137Cs source. Multilaser flow cytometry techniques using probes for live cell function were used to monitor the biochemical changes that occurred prior to the loss of surface membrane integrity. These showed increases in ... More
Differentiation of Phytophthora infestans sporangia from other airborne biological particles by flow cytometry.
AuthorsDay JP, Kell DB, Griffith GW
JournalAppl Environ Microbiol
PubMed ID11772606
'The ability of two different flow cytometers, the Microcyte (Optoflow) and the PAS-III (Partec), to differentiate sporangia of the late-blight pathogen Phytophthora infestans from other potential airborne particles was compared. With the PAS-III, light scatter and intrinsic fluorescence parameters could be used to differentiate sporangia from conidia of Alternaria or ... More
Accurate flow cytometric membrane potential measurement in bacteria using diethyloxacarbocyanine and a ratiometric technique.
AuthorsNovo D, Perlmutter NG, Hunt RH, Shapiro HM
JournalCytometry
PubMed ID10554181
'BACKGROUND: Membrane potential (MP) plays a critical role in bacterial physiology. Existing methods for MP estimation by flow cytometry are neither accurate nor precise, due in part to the heterogeneity of size of the particles analyzed. The ratio of a size- and MP-sensitive measurement, and an MP-independent, size-sensitive measurement, should ... More
A new method of monitoring membrane potential in rat hippocampal slices using cyanine voltage-sensitive dyes.
AuthorsDasheiff RM
JournalJ Neurosci Methods
PubMed ID4010331
'A novel application of voltage-sensitive dyes is described. Hippocampal slices in vitro accumulated voltage-sensitive cyanine dyes under conditions presumed to cause depolarization and hyperpolarization. Increasing extracellular potassium caused a depression of dye uptake that correlated linearly with the membrane potential calculated from the Goldman equation. Veratrine depressed dye uptake, and ... More
Preferential cytotoxicity for multidrug-resistant K562 cells using the combination of a photosensitizer and a cyanine dye.
AuthorsKanofsky JR, Sima PD
JournalJ Photochem Photobiol B
PubMed ID10836544
'The cyanine dye 1,1'',3,3,3'',3''-hexamethylindodicarbocyanine iodide (HIDC) protects K562 leukemia cells from photodynamic membrane damage caused by cis-di(4-sulfonatophenyl)diphenylporphine (TPPS2) and 420 nm light. This wavelength of light is chosen because it is absorbed by TPPS2, but not by HIDC. The photodynamic system studied may be useful as a model for antineoplastic ... More
Cyanine dye as monitor of membrane potentials in Escherichia coli cells and membrane vesicles.
AuthorsLetellier L, Shechter E
JournalEur J Biochem
PubMed ID118877
'The fluorescence response of a positively charged cyanine dye: 3,3''-dimethylindodicarbocyanine iodide can be specifically related to the generation in Escherichia coli cells and E. coli membrane vesicles of an electrical membrane potential induced either by substrate oxidation or by an artificially imposed potassium diffusion gradient. The energy-dependent quenching of the ... More
Mechanisms of rapid optical changes of potential sensitive dyes.
AuthorsWaggoner AS, Grinvald A
JournalAnn N Y Acad Sci
PubMed ID290293
Cell membrane potential analysis.
AuthorsShapiro HM
JournalMethods Cell Biol
PubMed ID7532258
Stress renders T cell blasts sensitive to killing by activated syngeneic NK cells.
AuthorsRabinovich BA, Shannon J, Su RC, Miller RG
JournalJ Immunol
PubMed ID10946262
Exposure of primary T cell blasts to stress in the forms of heat, hydrogen peroxide, or high-density growth conditions resulted in a state of enhanced susceptibility to killing by syngeneic IL-2-activated NK cells or lymphokine-activated killer cells, but not to killing by CTL. Cytotoxicity was perforin mediated and was not ... More
Lipophilic dye staining of Cryptococcus neoformans extracellular vesicles and capsule.
AuthorsNicola AM, Frases S, Casadevall A,
JournalEukaryot Cell
PubMed ID19465562
Cryptococcus neoformans is an encapsulated yeast that causes systemic mycosis in immunosuppressed individuals. Recent studies have determined that this fungus produces vesicles that are released to the extracellular environment both in vivo and in vitro. These vesicles contain assorted cargo that includes several molecules associated with virulence and implicated in ... More
Energy depletion inhibits phosphatidylinositol 3-kinase/Akt signaling and induces apoptosis via AMP-activated protein kinase-dependent phosphorylation of IRS-1 at Ser-794.
AuthorsTzatsos A, Tsichlis PN
JournalJ Biol Chem
PubMed ID17459875
Energy depletion activates AMP-activated protein kinase (AMPK) and inhibits cell growth via TSC2-dependent suppression of mTORC1 signaling. Long term energy depletion also induces apoptosis by mechanisms that are not well understood to date. Here we show that AMPK, activated by energy depletion, inhibited cell survival by binding to and phosphorylating ... More
Reconstitution of pure acetylcholine receptor in phospholipid vesicles and comparison with receptor-rich membranes by the use of a potentiometric dye.
AuthorsLüdi H, Oetliker H, Brodbeck U, Ott P, Schwendimann B, Fulpius BW
JournalJ Membr Biol
PubMed ID6876149
Acetylcholine receptor, isolated in Triton X-100 on a cobra alpha-neurotoxin affinity column was incorporated into unilamellar phospholipid vesicles by a detergent depletion method using Amberlite XAD-2. Vesicles of an average diameter of 25 nm were formed, as verified by freeze-fracture electron microscopy and gel filtration. 85 to 95% of the ... More
PCP and analogs prevent the proliferative response of T lymphocytes by lowering IL2 production. An effect related to the blockade of mitogen-triggered enhancement of free cytosolic calcium concentration.
AuthorsDornand J, Kamenka JM, Bartegi A, Mani JC
JournalBiochem Pharmacol
PubMed ID2961341
The psychotomimetic drug PCP displays a vast array of known pharmacological effects, among them its capacity to affect cation transport in nervous and myocardiac tissues. Since increased movements of cations are essential for the immune responses, it has been mentioned that PCP could also depress immune functions by this mechanism. ... More
Simultaneous detection of mitochondrial respiratory chain activity and reactive oxygen in digitonin-permeabilized cells using flow cytometry.
AuthorsPham NA, Robinson BH, Hedley DW
JournalCytometry
PubMed ID11084609
BACKGROUND: Increased mitochondrial generation of reactive oxygen intermediates (ROI) due to defective respiratory chain activity has been implicated in physiological processes such as apoptosis, in the pathogenesis of mitochondrial diseases, and as part of the normal aging process. Established methods addressing activity of the respiratory chain complexes have been limited ... More
The mechanism of voltage-sensitive dye responses on sarcoplasmic reticulum.
AuthorsBeeler TJ, Farmen RH, Martonosi AN
JournalJ Membr Biol
PubMed ID7277473
The mechanism of voltage-sensitive dye responses was analyzed on sarcoplasmic reticulum vesicles to assess the changes in membrane potential related to Ca2+ transport. The absorbance and fluorescence responses of 3,3'-diethyl-2,2'-indodicarbocyanine and oxonol VI during ATP-dependent Ca2+ transport are influenced by the effect of accumulated Ca2+ upon the surface potential of ... More
Structure and cholesterol domain dynamics of an enriched caveolae/raft isolate.
AuthorsGallegos AM, McIntosh AL, Atshaves BP, Schroeder F
JournalBiochem J
PubMed ID15149285
Despite the importance of cholesterol in the formation and function of caveolar microdomains in plasma membranes, almost nothing is known regarding the structural properties, cholesterol dynamics or intracellular factors affecting caveolar cholesterol dynamics. A non-detergent method was employed to isolate caveolae/raft domains from purified plasma membranes of murine fibroblasts. A ... More
Inhibitory effects of two structurally related carbocyanine laser dyes on the activity of bovine heart mitochondrial and Paracoccus denitrificans NADH-ubiquinone reductase. Evidence for a rotenone-type mechanism.
AuthorsAnderson WM, Chambers BB, Wood JM, Benninger L
JournalBiochem Pharmacol
PubMed ID1900156
Two cationic, lipophilic laser dyes, 1,1',3,3,3',3'-hexamethylindodicarbocyanine iodide (HIDC) and 1,1',3,3,3',3'-hexamethylindotricarbocyanine iodide (HITC), inhibit bovine heart mitochondrial and Paracoccus denitrificans NADH oxidase activities. The mitochondrial I50 values were 0.5 microM (HIDC) and 1.2 microM (HITC), and the P. denitrificans I50 values 1.2 microM (HIDC) and 1.5 microM (HITC). Neither succinate nor ... More
Segregation of anionic lipophiles in bilayers monitored by binding of cationic dye NK-529.
AuthorsYu BZ, Jain MK
JournalBiochim Biophys Acta
PubMed ID2923894
Fluorescence emission properties of a cationic indodicarbocyanine dye, NK-529, bound to anionic and zwitterionic vesicles, are examined under a variety of conditions to monitor lateral distribution of anionic amphiphiles in bilayers as a function of their phase properties. The change in the fluorescence properties of NK-529 arises from the binding ... More