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1.
Vox Sang ; 108(2): 103-12, 2015 Feb.
Article in English | MEDLINE | ID: mdl-25471135

ABSTRACT

Cryopreserved (frozen) red blood cells have been used in transfusion medicine since the Vietnam war. The main method to freeze the red blood cells is by usage of glycerol. Although the usage of cryopreserved red blood cells was promising due to the prolonged storage time and the limited cellular deterioration at subzero temperatures, its usage have been hampered due to the more complex and labour intensive procedure and the limited shelf life of thawed products. Since the FDA approval of a closed (de) glycerolization procedure in 2002, allowing a prolonged postthaw storage of red blood cells up to 21 days at 2-6°C, cryopreserved red blood cells have become a more utilized blood product. Currently, cryopreserved red blood cells are mainly used in military operations and to stock red blood cells with rare phenotypes. Yet, cryopreserved red blood cells could also be useful to replenish temporary blood shortages, to prolong storage time before autologous transfusion and for IgA-deficient patients. This review describes the main methods to cryopreserve red blood cells, explores the quality of this blood product and highlights clinical settings in which cryopreserved red blood cells are or could be utilized.


Subject(s)
Blood Preservation/methods , Cryopreservation/methods , Erythrocytes/cytology , Transfusion Medicine/methods , Blood Preservation/standards , Cryopreservation/standards , Cryoprotective Agents , Humans
2.
Vox Sang ; 108(3): 219-25, 2015 Apr.
Article in English | MEDLINE | ID: mdl-25471217

ABSTRACT

BACKGROUND AND OBJECTIVES: The use of a functionally closed system (ACP215, Haemonetics) for (de)glycerolization of RBCs allows for prolonged post-thaw storage. Currently, glycerolization is followed by supernatant glycerol reduction before freezing. The aim of this study was to investigate the influence of supernatant glycerol reduction before freezing on the stability of thawed, deglycerolized RBCs during subsequent cold storage. MATERIALS AND METHODS: Leucoreduced RBCs were stored for 6 days at 2-6°C before glycerolization. The RBCs were pooled and split, and glycerol was added using the ACP215 to a final concentration of 40%. Units were either frozen as such (n = 4) or supernatant reduced before freezing (n = 4). After storage at -80°C, the units were thawed, deglycerolized and resuspended in SAGM. An additional sixteen units, frozen without supernatant reduction, were resuspended in either AS-3 (n = 8) or SAGM (n = 8) after deglycerolization. During cold storage (2-6°C), the red cells were analysed for their stability and in vitro quality. RESULTS: The freeze-thaw-wash recovery was comparable for both volume reduced and non-reduced units. During post-thaw storage in SAGM, non-glycerol reduced units showed significantly less potassium leakage and haemolysis and higher ATP levels. AS-3 strongly reduced haemolysis during post-thaw storage of non-glycerol reduced units: haemolysis remained below 0.8% for up to 28 days of storage. CONCLUSION: Omitting glycerol supernatant reduction before freezing simplifies the cryopreservation procedure and increases the stability and therefore the outdating period of thawed RBCs. This increases the practical applicability of cryopreserved RBCs in both civil (rare blood) and military blood transfusion practice.


Subject(s)
Blood Preservation/methods , Cryopreservation/methods , Cryoprotective Agents/pharmacology , Erythrocytes/drug effects , Glycerol/pharmacology , Humans
3.
Cancer Res ; 54(21): 5561-7, 1994 Nov 01.
Article in English | MEDLINE | ID: mdl-7923197

ABSTRACT

Reactive oxygen species are used to eradicate malignant cells in photodynamic therapy as well as in other cancer therapies. Despite many efforts, the pathways leading to cellular damage and cell killing due to the action of these species are poorly understood. In previous studies with hematoporphyrin derivative-sensitized L929 murine fibroblasts, the only parameter for which a relation with photodynamically induced reproductive cell death could not be excluded was inhibition of DNA excision repair. The present results show that loss of clonogenicity of these cells in fact is related to a series of effects, including the development of slight, irreperable DNA damage, a virtually complete inhibition of poly(ADP-ribosyl)ation activation, a transient elevation of the intracellular calcium concentration and, after a lag time of about 8 h, DNA fragmentation caused by endonuclease activity. This conclusion is supported by the observation that photodynamic treatment inhibited the repair of X-ray-induced DNA strand breaks and suppressed X-ray- and methyl methanesulfonate-induced enhancement of poly(ADP-ribosyl)ation. Our experimental results further suggest that in this cell line the photodynamically induced inhibition of enhanced poly(ADP-ribosyl)ation could well be involved in inhibition of repair of DNA strand breaks and in activation of endonuclease activity.


Subject(s)
DNA Damage , DNA Repair , Hematoporphyrin Photoradiation , Poly(ADP-ribose) Polymerases/metabolism , Animals , Benzamides/pharmacology , Cell Line , DNA Damage/drug effects , DNA Damage/radiation effects , DNA Repair/drug effects , DNA Repair/radiation effects , Fibroblasts/drug effects , Fibroblasts/radiation effects , Methyl Methanesulfonate/pharmacology , Mice , Oxidative Stress , Poly(ADP-ribose) Polymerase Inhibitors , Tumor Cells, Cultured , Urinary Bladder Neoplasms/drug therapy , Urinary Bladder Neoplasms/genetics , Urinary Bladder Neoplasms/metabolism
4.
Biochim Biophys Acta ; 1236(1): 81-8, 1995 May 24.
Article in English | MEDLINE | ID: mdl-7794958

ABSTRACT

Binding of protoporphyrin caused a perturbation of the erythrocyte membrane, as reflected by a change in cell shape from discoid to echinocyte, and a concomitant increase in mean cellular volume and K(+)-loss. Protoporphyrin-induced changes could be prevented by the presence of BaCl2, whereas binding of protoporphyrin was not affected. Exposure of erythrocytes to hydrogen peroxide leads to K(+)-leakage and lipid peroxidation. In de presence of protoporphyrin, H2O2-induced K(+)-leakage was enhanced, whereas lipid peroxidation was inhibited. The increase in H2O2-induced K(+)-leakage by protoporphyrin was not affected by diamide or various K+ channel blockers, but could be prevented by the addition of BaCl2. The inhibition of lipid peroxidation, on the other hand, was not affected by BaCl2. These results indicate that the enhancement of H2O2-induced K(+)-leakage was most likely caused by the change in cell shape. Addition of chlorpromazine and promethazine, positively charged molecules that induce stomatocytosis, did not cause an enhancement of H2O2-induced K(+)-leakage.


Subject(s)
Erythrocytes/drug effects , Hydrogen Peroxide/pharmacology , Oxidative Stress/drug effects , Protoporphyrins/pharmacology , Cell Size/drug effects , Drug Interactions , Erythrocyte Membrane/drug effects , Erythrocytes/metabolism , Humans , Lipid Peroxidation/drug effects , Potassium/metabolism , Protoporphyrins/antagonists & inhibitors
5.
Biochim Biophys Acta ; 979(2): 215-20, 1989 Feb 27.
Article in English | MEDLINE | ID: mdl-2522321

ABSTRACT

Photodynamic treatment of murine L929 fibroblasts with hematoporphyrin derivative caused inhibition of the 2-aminoisobutyric acid transport system. This was reflected by an increase in the apparent Km with a constant Vmax, indicating impairment of the carrier function rather than a decrease of the number of transport sites. Hyperthermic treatment of these cells resulted in a moderate decrease of the activity of the 2-aminoisobutyric acid transport system. Overall protein synthesis was severely inhibited both by photodynamic treatment and by hyperthermia. Hyperthermia subsequent to photodynamic treatment resulted in an additive inhibition of 2-aminoisobutyric acid transport and of protein synthesis. After photodynamic treatment both 2-aminoisobutyric acid transport and protein synthesis were repaired. The repair of 2-aminoisobutyric acid transport depended on protein synthesis, as shown by the virtually complete blockage of repair by anisomycin. After hyperthermia (either alone or subsequent to photodynamic treatment), no recovery of 2-aminoisobutyric acid transport was observed, although protein synthesis was restored to the initial level. Apparently, hyperthermia subsequent to photodynamic treatment blocks the repair of photodynamically induced damage of this transport system. The experimental results further indicate that protein synthesis is not the rate-determining step for the repair of 2-aminoisobutyric acid transport, although it is necessary in this process. Cell survival was decreased both by photodynamic treatment and by hyperthermia. The combined effects of these two treatments were additive. It is discussed that these results indicate that photodynamic inhibition of 2-aminoisobutyric acid transport is not causally related to loss of clonogenicity, contrary to earlier suggestions.


Subject(s)
Aminoisobutyric Acids/metabolism , Cell Membrane/metabolism , Fibroblasts/metabolism , Hematoporphyrins/pharmacology , Hot Temperature , Light , Animals , Anisomycin/pharmacology , Biological Transport/drug effects , Cell Line , Cell Membrane/drug effects , Fibroblasts/drug effects , Hematoporphyrin Derivative , Hydrogen Peroxide/pharmacology , Kinetics , Mice , Protein Biosynthesis
6.
Biochim Biophys Acta ; 1235(2): 428-36, 1995 May 04.
Article in English | MEDLINE | ID: mdl-7756353

ABSTRACT

In the presence of albumin Merocyanine 540 (MC540) exhibits a very limited binding to the outer surface of the membrane of normal erythrocytes, whereas pronounced binding is observed to leukemia cells. To find out whether this difference is due to differences in the composition or structural organization of the cell membrane we analyzed effects of a number of covalent and non-covalent perturbations of the red cell membrane on the binding and fluorescence characteristics of membrane-bound MC540. It is shown that exposure of the cells to cationic chlorpromazine, neuraminidase or photodynamic treatment with AlPcS4 as sensitizer caused a limited increase (30-50%) of MC540 binding, together with a red shift of the fluorescence emission maximum and an increase of the relative fluorescence quantum yield of membrane-bound MC540. Other forms of perturbation of the membrane structure, like hyperthermia (48 degrees C) and treatments that produce a decrease of phospholipid asymmetry in addition to accelerated flip-flop, did not result in increased MC540 binding, but did cause a red shift of the fluorescence emission maximum and an increase of the relative fluorescence quantum yield. These changes in fluorescence properties indicate a penetration of the dye into more hydrophobic regions in the membrane. MC540, bound to Brown Norway myelocytic leukemia cells, exhibited a red shift of the fluorescence emission maximum and an increased relative fluorescence quantum yield as compared to MC540 bound to untreated erythrocytes. These changes were of the same order of magnitude as in photodynamically treated red blood cells. Dye binding per surface area, however, was about 3-times higher with these leukemia cells than with photodynamically treated red blood cells. This demonstrates that certain perturbations of the erythrocyte membrane evoked a MC540 binding that became qualitatively comparable to the dye binding to leukemia cells, although dye binding per surface area was still significantly lower.


Subject(s)
Erythrocyte Membrane/metabolism , Leukemia, Myeloid/metabolism , Pyrimidinones/metabolism , Cell Membrane/chemistry , Cell Membrane/metabolism , Chlorpromazine/pharmacology , Cholesterol/physiology , Erythrocyte Membrane/chemistry , Erythrocyte Membrane/drug effects , Hot Temperature , Humans , Indoles/pharmacology , Light , Lipid Bilayers/chemistry , Neuraminidase/pharmacology , Organometallic Compounds/pharmacology , Radiation-Sensitizing Agents , Spectrometry, Fluorescence , Tumor Cells, Cultured
7.
Biochim Biophys Acta ; 1201(1): 23-8, 1994 Sep 28.
Article in English | MEDLINE | ID: mdl-7918578

ABSTRACT

The photochemical degradation of histidine, cysteine and tyrosine with hematoporphyrin as sensitizer was potentiated by the presence of Sephadex, BioGel or Percoll particles. This effect could only partly be explained by binding of the sensitizer to the gel particles, leading a.o. to monomerization of aggregated sensitizer molecules in the aqueous environment. The hematoporphyrin triplet state life time increased from 250 microseconds in phosphate buffer to 1992 microseconds in the presence of 50% Percoll. Most likely the effect of the gel particles on the sensitizer triplet state is, at least partly, mediated by the solvent. A plausible explanation seems to be that the vicinal water structure at the particle interface stabilizes the sensitizer triplet.


Subject(s)
Hematoporphyrins/chemistry , Photochemistry/methods , Cysteine/chemistry , DEAE-Dextran , Histidine/chemistry , Photochemotherapy , Povidone , Silicon Dioxide , Tyrosine/chemistry
8.
Biochim Biophys Acta ; 1012(3): 237-42, 1989 Aug 15.
Article in English | MEDLINE | ID: mdl-2758036

ABSTRACT

Photodynamically induced loss of clonogenicity of murine L929 fibroblasts and Chinese hamster ovary K1 epithelial cells was determined with two different assays. It appeared that the loss of clonogenicity was much higher when 20 cells/cm2 were incubated with hematoporphyrin derivative (HPD) and illuminated, than when confluent cell layers were incubated with the same amount of HPD and illuminated prior to plating out. This dependency of cell killing on the experimental protocol was also observed when protoporphyrin (90-95% pure) was used as photosensitizer, but not when the cells were photodynamically treated with rose bengal or exposed to mitomycin C. Further, when cell layers were incubated with the residual solution that remained after the previous incubation of a confluent cell layer with HPD, illumination of these layers appeared to be almost non-toxic, although the overall porphyrin concentration in the residual solution was only slightly lower than in HPD. These results indicate that the porphyrins, responsible for loss of clonogenicity, are present in relatively small amounts in HPD and unpurified protoporphyrin and are preferentially taken up by the cells. Although 2-aminoisobutyric acid transport and DNA synthesis are among the most photosensitive targets with HPD, photodynamic treatment of L929 cells with the residual solution did not result in inhibition of the transport system and DNA synthesis. In contrast, the K+ content of the cells still decreased considerably, when utilizing the porphyrins, remaining in the residual solution as sensitizer. This indicates that under the present experimental conditions the disturbance of the membrane barrier function does not contribute to loss of clonogenicity of these cells and, moreover, that the photodynamically induced K+ leakage is caused by a component of HPD other than inhibition of 2-aminoisobutyric acid transport and DNA synthesis.


Subject(s)
Hematoporphyrins/metabolism , L Cells/metabolism , Ovary , Porphyrins/metabolism , Animals , Clone Cells/drug effects , Clone Cells/metabolism , Clone Cells/pathology , Cricetinae , Cricetulus , Epithelium/drug effects , Epithelium/metabolism , Epithelium/pathology , Female , Fibroblasts/drug effects , Fibroblasts/metabolism , Fibroblasts/pathology , L Cells/drug effects , L Cells/pathology , Mice , Photolysis , Porphyrins/toxicity , Protoporphyrins
9.
Biochim Biophys Acta ; 1278(2): 247-53, 1996 Jan 31.
Article in English | MEDLINE | ID: mdl-8593283

ABSTRACT

The interaction of the red cell membrane with merocyanine 540 or protoporphyrin led to four phenomena, most probably interrelated. (i) The morphology changed from the normal discoid to an echinocytic form. This morphological change persisted when followed over a period of 24 h. (ii) Simultaneously, cell deformability was decreased, as revealed by viscosity measurements and a cell-filtration technique. (iii) Both drugs caused swelling of the erythrocytes in isotonic medium, due to a very-short-term increased permeability of the membrane, also for larger molecules such as lactose. The pathway of this temporary leak seems to be unrelated to the Na+/K+ -ATPase, the K+/Cl- and the Na+/K+/Cl- cotransport systems, the Ca2+-activated Gardos pathway, the oxidation/deformation-activated leak pathway and the so-called residual transport route. Despite the morphological changes, K+-leakage induced by mechanical stress was not increased. (iv) During osmotic swelling, the critical hemolytic volume was found to be increased in the presence of either merocyanine 540 or protoporphyrin. The increase critical volume protected erythrocytes against osmotic hemolysis.


Subject(s)
Antiviral Agents/pharmacology , Erythrocyte Membrane/drug effects , Photosensitizing Agents/pharmacology , Protoporphyrins/pharmacology , Pyrimidinones/pharmacology , Cell Membrane Permeability , Chemical Phenomena , Chemistry, Physical , Erythrocyte Deformability/drug effects , Erythrocyte Membrane/chemistry , Erythrocyte Membrane/physiology , Erythrocytes/cytology , Erythrocytes/drug effects , Erythrocytes/physiology , Hemolysis , Humans , Osmosis , Phospholipids/blood , Viscosity
10.
Free Radic Biol Med ; 21(2): 181-8, 1996.
Article in English | MEDLINE | ID: mdl-8818633

ABSTRACT

The photophysical and photochemical properties of porphyrins were profoundly changed upon addition of rhodamine 123. The Soret band of the porphyrins shifted to higher wavelengths, the fluorescence yield of the porphyrins decreased with unaltered decay rates, and their triplet state was quenched. These observations indicate a strong interaction between porphyrins and rhodamine 123 and formation of 1:1 nonfluorescent complexes, of which the binding constants were determined. Illumination of a porphyrin in the presence of rhodamine 123 resulted in the formation of a porphyrin radical cation, which could be detected with ESR spectroscopy. Quenching of the triplet state of the porphyrins by rhodamine 123 resulted in a decreased singlet oxygen yield and a decrease of the photooxidation of histidine, methionine, tyrosine, and tryptophan. However, the oxidation of thiol compounds was increased and the stoichiometry of the reaction between cysteine and oxygen changed from 2 to 3.8 mol cysteine/ mol oxygen. These results show that the presence of rhodamine 123 converted the for porphyrins prevalent energy transfer (type II) reaction to an electron transfer (type I) reaction.


Subject(s)
Photosensitizing Agents/pharmacology , Porphyrins/pharmacology , Rhodamines/pharmacology , Cations , Electron Spin Resonance Spectroscopy , Free Radicals , Histidine/chemistry , Light , Methionine/chemistry , Oxygen/chemistry , Photochemistry , Porphyrins/chemistry , Rhodamine 123 , Rhodamines/chemistry , Singlet Oxygen , Spectrometry, Fluorescence , Spectrophotometry , Tryptophan/chemistry , Tyrosine/chemistry
11.
Cancer Lett ; 159(1): 23-32, 2000 Oct 16.
Article in English | MEDLINE | ID: mdl-10974402

ABSTRACT

This work relates to studies on modes of phototoxicity by protoporphyrin (PpIX) after incubation of 5-aminolevulinic acid (5-ALA) on cultured cells. Lipid peroxidation in the 5-ALA incubated primary adenocarcinoma cells from the rectosigmoid colon (WiDr cells) was determined by measurement of protein-associated thiobarbituric acid reactive substances (TBARS). TBARS were increased 2-fold in cells treated with 2 mM 5-ALA for 3.5 h in serum enriched medium. After illumination of 5-ALA incubated cells, TBARS were formed in a light dose dependent manner. TBARS analysis were compared with high-performance liquid chromatography (HPLC) analysis of malondialdehyde, and results indicate that 90% of the thiobarbituric reactive substances were due to malondialdehyde. Pretreating WiDr cells with alpha-tocopherol for 48 h inhibits the cytotoxic effect of 5-ALA and increases 5-fold the light dose needed to kill 50% of the cells. Pretreatment with alpha-tocopherol shows a considerable decrease (about 80%) on TBARS formation after illumination. The cellular content of alpha-tocopherol was determined by HPLC and found to be 15.3 pmol/10(6) cells.


Subject(s)
Adenocarcinoma/prevention & control , Aminolevulinic Acid/pharmacology , Colonic Neoplasms/prevention & control , Lipid Peroxidation/drug effects , Photosensitizing Agents/pharmacology , Adenocarcinoma/metabolism , Adenocarcinoma/pathology , Cell Survival/drug effects , Cell Survival/radiation effects , Colonic Neoplasms/metabolism , Colonic Neoplasms/pathology , Dose-Response Relationship, Radiation , Humans , Light , Malondialdehyde/metabolism , Malondialdehyde/radiation effects , Thiobarbituric Acid Reactive Substances/metabolism , Thiobarbituric Acid Reactive Substances/radiation effects , Tumor Cells, Cultured/drug effects , Tumor Cells, Cultured/metabolism , Tumor Cells, Cultured/radiation effects , Vitamin E/pharmacokinetics , Vitamin E/pharmacology
12.
Photochem Photobiol ; 67(6): 729-33, 1998 Jun.
Article in English | MEDLINE | ID: mdl-9648538

ABSTRACT

Illumination of erythrocytes in the presence of merocyanine 540 (MC540) resulted in changed binding characteristics of MC540, i.e. a red shift in the emission maximum of bound dye with an increase in the relative fluorescence quantum yield. Aluminum phthalocyanine tetrasulfonate-mediated photodynamic treatment, before addition of MC540, resulted in a comparable change in the MC540-binding characteristics with, in addition, an increase in the concentration of MC540 in the membrane. Both photodynamic treatments induce depolarization of the red cell membrane, with a dose dependency comparable to that of changed MC540 binding. Also depolarization, induced by incubation of the cells with A23187 in the presence of Ca2+ in high [K+] buffer, resulted in similar changes in the MC540 binding characteristics. These results indicate a relation between photodynamically induced membrane depolarization and changed MC540-binding characteristics. Hyperpolarization induced by incubation with A23187 in low [K+] buffer resulted in decreased binding of MC540. In accordance, the MC540-mediated photodamage to red cells decreased upon hyperpolarization of the cells. The results indicate that the binding of MC540 to erythrocytes is strongly dependent on the membrane potential and that hyperpolarization of the membrane could be a possible protection mechanism for erythrocytes against MC540-mediated photodynamic damage.


Subject(s)
Erythrocyte Membrane/drug effects , Photosensitizing Agents/blood , Photosensitizing Agents/pharmacology , Pyrimidinones/blood , Pyrimidinones/pharmacology , Dose-Response Relationship, Radiation , Erythrocyte Membrane/physiology , Humans , In Vitro Techniques , Light , Membrane Potentials/drug effects
13.
Photochem Photobiol ; 71(3): 341-6, 2000 Mar.
Article in English | MEDLINE | ID: mdl-10732453

ABSTRACT

Merocyanine 540 (MC540)-mediated photodynamic damage to erythrocytes was strongly reduced when illumination was performed at pH 8.5 as compared to pH 7.4. This could be explained by high pH-mediated hyperpolarization of the erythrocyte membrane, resulting in decreased MC540 binding at pH 8.5. In accordance, the MC540-mediated photooxidation of open ghosts was not inhibited at pH 8.5. Photoinactivation of vesicular stomatitis virus (VSV) was not inhibited at pH 8.5. This suggests that illumination at increased pH could be an approach to protect red blood cells selectively against MC540-mediated virucidal phototreatment. With tetrasulfonated aluminum phthalocyanine (AIPcS4) as photosensitizer, damage to erythrocytes, open ghosts and VSV was decreased when illuminated at pH 8.5. A decreased singlet oxygen yield at high pH could be excluded. The AIPcS4-mediated photooxidation of fixed erythrocytes was strongly dependent on the cation concentration in the buffer, indicating that the surface potential may affect the efficacy of this photosensitizer. This study showed that altering the environment of the target could increase both the efficacy and the specificity of a photodynamic treatment.


Subject(s)
Erythrocyte Membrane/drug effects , Indoles/adverse effects , Organometallic Compounds/adverse effects , Photochemotherapy/adverse effects , Pyrimidinones/adverse effects , Erythrocyte Membrane/radiation effects , Erythrocytes/drug effects , Erythrocytes/radiation effects , Histidine/drug effects , Histidine/radiation effects , Humans , Hydrogen-Ion Concentration , In Vitro Techniques , Photobiology , Photosensitizing Agents/adverse effects , Vesicular stomatitis Indiana virus/drug effects , Vesicular stomatitis Indiana virus/radiation effects
14.
Photochem Photobiol ; 66(2): 209-13, 1997 Aug.
Article in English | MEDLINE | ID: mdl-9277139

ABSTRACT

In several recent studies it has been shown that protein kinase C (PKC) activity may either potentiate or antagonize cell killing by different cytotoxic agents. These apparently conflicting observations suggest that the effects of PKC activity on cell survival may depend on the different properties of different cell types but do not exclude the possibility that the effects may also depend on the nature of the cytotoxic agent. In this context the effects of PKC activation and PKC inhibition or down-regulation on Chinese hamster ovary (CHO) cell survival after photodynamic treatment and ionizing radiation were studied. It appeared that PKC activation by short-term incubation with 12-O-tetradecanoyl-phorbol-13-acetate (TPA) protected CHO cells against ionizing radiation but, in contrast, sensitized the cells to photodynamic treatment. Conversely, inhibition of PKC by H7 and down-regulation of PKC activity by prolonged incubation with TPA sensitized CHO cells to ionizing radiation but protected the cells against photodynamic treatment. These results demonstrate that in one particular cell type PKC activity may have opposite effects on cell survival following cellular damage, depending on the nature of the cytotoxic agent.


Subject(s)
Photochemotherapy , Protein Kinase C/metabolism , 1-(5-Isoquinolinesulfonyl)-2-Methylpiperazine/pharmacology , Animals , CHO Cells , Cell Cycle , Cell Survival/drug effects , Cell Survival/radiation effects , Cricetinae , Down-Regulation , Enzyme Activation , Enzyme Inhibitors/pharmacology , Tetradecanoylphorbol Acetate/pharmacology , Tumor Cells, Cultured
15.
Photochem Photobiol ; 66(6): 860-5, 1997 Dec.
Article in English | MEDLINE | ID: mdl-9421972

ABSTRACT

It has been shown previously that the efficiency of photodynamic therapy (PDT) both in vivo and in vitro is dependent on fluence rate. In this study, different in vitro experiments showed that tetrasulfonated aluminum phthalocyanine (AIPcS4) is more efficient in photosensitization if the light is delivered at low fluence rate. Erythrocyte damage, virus inactivation and photooxidation of reduced glutathione (GSH) and histidine were all enhanced if light was delivered at 100 W/m2 as compared to 500 W/m2. Bleaching did not occur under these conditions. Oxygen depletion, shown to be important in fluence rate effects observed in vivo, does not seem to be involved. On theoretical grounds saturation of the triplet state is not likely under these conditions. A possible explantation for the observed fluence rate effects might be found in different reaction pathways, that are favored under high or low fluence rate illuminations. These reactions might involve uni- or bimolecular reactions of intermediate products, resulting in less efficiency at higher fluence rate. It proves to be important, under all circumstances, to monitor fluence rate, because a change in fluence rate, even with similar total fluences, might influence photobiological results in an unexpected way.


Subject(s)
Indoles/pharmacology , Organometallic Compounds/pharmacology , Photosensitizing Agents/pharmacology , Erythrocytes/drug effects , Humans , Indoles/chemistry , Kinetics , Organometallic Compounds/chemistry , Oxidation-Reduction , Photosensitizing Agents/chemistry , Vesicular stomatitis Indiana virus/drug effects
16.
J Photochem Photobiol B ; 60(1): 50-60, 2001 Apr.
Article in English | MEDLINE | ID: mdl-11386681

ABSTRACT

To describe the action mechanisms of Bacteriochlorin a (BCA), a second generation photosensitizer, in phosphate buffer (PB) and in dimyristoyl phosphatidylcholine (DMPC) liposomes we carried out oxygen consumption and ESR measurements. In PB, where BCA was in a monomer-dimer equilibrium, our results suggested that the oxygen consumption was related to the BCA monomers concentration in solution. Incorporation of BCA in DMPC liposomes, by promoting the monomerization of BCA, increased 9-fold the oxygen consumption in comparison to the value in PB. The use of specific singlet oxygen quenchers (Azide and 9,10-Anthracenedipropionic acid) in ESR and oxygen consumption experiments allowed us to assert that BCA was mainly a type II sensitizer when it was incorporated in DMPC. Finally, the cell survival of WiDr cells after a PDT treatment was measured for cells incubated with BCA in cell culture medium and cells incubated with BCA in DMPC. Irrespective of the dye concentration, the cell survival was lower when liposomes were used. This effect could be the result of a better BCA monomerization and/or a different BCA uptake in cells.


Subject(s)
Photosensitizing Agents/metabolism , Porphyrins/metabolism , Buffers , Cell Survival , Dimerization , Dimyristoylphosphatidylcholine/metabolism , Humans , Liposomes , Oxygen/metabolism , Oxygen Consumption , Phosphates , Photosensitizing Agents/adverse effects , Porphyrins/adverse effects , Singlet Oxygen , Temperature , Tumor Cells, Cultured
17.
J Photochem Photobiol B ; 49(2-3): 162-70, 1999 Apr.
Article in English | MEDLINE | ID: mdl-10392465

ABSTRACT

Human adenocarcinoma cells of the line WiDr have been treated with 2 mM 5-aminolaevulinic acid (5-ALA) in the presence of 10% foetal calf serum. The treatment induces a linear accumulation of protoporphyrin IX (PpIX) for at least 7.5 h. After 7.5 h of incubation about 45% of the PpIX accumulated is cell-bound, while the rest is found in the medium (25%) or lost from the cells during washing with phosphate-buffered saline (30%). Exposure to white light at an intensity of 30 W/m2 for 18 min results in 95% reduction of clonogenicity in cells treated with 2 mM 5-ALA for 3.5 h. The enzymatic activities of enzymes located in cytosol (glyceraldehyde 3-phosphate dehydrogenase and lactate dehydrogenase) and lysosomes (acid phosphatase and beta-glucuronidase) are not influenced by a 5-ALA and light treatment inactivating about 35% of the cells. The MTT assay, which reflects mitochondrial dehydrogenase activity, but not succinate dehydrogenase, is partly inhibited by the same treatment. Treatment with 5-ALA in the absence of light increases O2 consumption by a factor of two, while the O2 consumption is inhibited when 5-ALA treatment is combined with exposure to light. In addition, 5-ALA and light exposure enhance accumulation of rhodamine 123 by 40% and reduce the intracellular ATP level by 25%. Confocal laser scanning microscopical analysis indicates granular perinuclear localization of the PpIX formed by 5-ALA treatment. In conclusion, photodynamic treatment using 5-ALA as a prodrug induces damage to mitochondrial function without inhibiting lysosomal and cytosolic marker enzymes.


Subject(s)
Aminolevulinic Acid/therapeutic use , Colonic Neoplasms/drug therapy , Photosensitizing Agents/therapeutic use , Adenosine Triphosphate/metabolism , Biomarkers, Tumor , Fluorescent Dyes/pharmacokinetics , Heptanoates/pharmacology , Humans , Microscopy, Confocal , Microscopy, Fluorescence , Oxygen Consumption/drug effects , Photochemotherapy , Protoporphyrins/metabolism , Rhodamine 123/pharmacokinetics , Time Factors , Tumor Cells, Cultured
19.
Vox Sang ; 91(3): 244-51, 2006 Oct.
Article in English | MEDLINE | ID: mdl-16958837

ABSTRACT

BACKGROUND AND OBJECTIVES: Loss of phospholipid asymmetry in the membrane of red blood cells (RBC) results in exposure of phosphatidylserine (PS) and to subsequent removal from the circulation. In this study, we investigated the effect of long-term storage of RBCs on two activities affecting phospholipid asymmetry: the ATP-dependent aminophospholipid translocase (or flippase, transporting PS from the outer to the inner leaflet) and phospholipid scrambling (which will move PS from the inner to the outer leaflet). MATERIALS AND METHODS: Standard leukodepleted RBC concentrates were stored in saline-adenine-glucose-mannitol (SAGM) at 4 degrees C for up to 7 weeks. PS exposure was determined by measurement of AnnexinV-FITC binding to the cells, flippase activity by measurement of the inward translocation of NBD-labelled PS. Scrambling activity was determined by following the inward translocation of fluorescent NBD-phosphatidylcholine. In parallel, intracellular ATP levels were determined. RESULTS: PS exposure amounted to only 1.5 +/- 0.3% positive cells (n = 8) after 5 weeks of storage, which slightly increased to 3.5 +/- 0.7% (n = 8) after 7 weeks of storage. Flippase activity started to decrease after 21 days of storage and reached 81 +/- 5% of the control value after 5 weeks of storage (n = 6) and 59 +/- 6% (n = 6) after 7 weeks. Also in RBC obtained by apheresis, flippase activity decreased upon storage. Scrambling activity remained virtually absent during storage, explaining the low PS exposure despite the decrease in flippase activity. Rejuvenation of RBC after 7 weeks to increase ATP levels only partially restored flippase activity, but in combination with a correction of the intracellular pH to that of fresh cells, almost complete restoration was achieved. The decrease in flippase activity after prolonged storage did make the RBCs more prone to PS exposure after activation of phospholipid scrambling. CONCLUSION: This study shows that, although PS exposure remains low, prolonged storage does compromise the RBC membrane by affecting flippase activity. When the metabolic changes induced by storage are corrected, flippase activity can be restored.


Subject(s)
Blood Preservation , Erythrocytes/enzymology , Lipid Bilayers/metabolism , Phosphatidylserines/metabolism , Phospholipid Transfer Proteins/metabolism , Adenosine Triphosphate/analysis , Blood Preservation/adverse effects , Blood Preservation/methods , Erythrocyte Membrane/enzymology , Erythrocyte Transfusion/methods , Hemolysis , Humans , Phospholipid Transfer Proteins/chemistry , Refrigeration/adverse effects , Time Factors
20.
Vox Sang ; 91(2): 111-8, 2006 Aug.
Article in English | MEDLINE | ID: mdl-16907871

ABSTRACT

BACKGROUND AND OBJECTIVES: Photodynamic treatment (PDT) with the cationic porphyrin, mono-phenyl-tri-(N-methyl-4-pyridyl)-porphyrin chloride [Tri-P(4)], has previously been shown to be effective at inactivating vesicle stomatitis virus (VSV) in red cell concentrates (RCC) with limited damage to red blood cells (RBC). The aim of this study was to determine the pathogen-inactivating capacity of PDT with Tri-P(4) for a broader range of pathogens and to establish the associated effect on in vitro RBC quality. MATERIALS AND METHODS: A series of viruses and bacteria was spiked into 60% RCC. Pathogen inactivation was determined after PDT with 25 microm Tri-P(4) and red light up to 360 kJ/m2. Human immunodeficiency virus (HIV)-infected cells were evaluated for cell death induction, and RCC were analysed for the induction of haemolysis and ATP content. RESULTS: For the lipid-enveloped viruses bovine viral diarrhoea virus, HIV and pseudorabies virus, and for the Gram positive bacterium, Staphylococcus aureus, and the Gram-negative bacteria, Pseudomonas aeruginosa and Yersinia enterolitica, inactivation of > or = 5 log10 was measured after 60 min of PDT with Tri-P(4). The required treatment time to achieve this level of inactivation was four times longer than required for VSV. For cell-associated HIV, only 1.7 log10 of inactivation was found, despite clear induction of cell death of HIV-infected cells. The non-enveloped virus, canine parvovirus, was completely resistant to the treatment. PDT of RCC with Tri-P(4) for 60 min, and subsequent storage in AS-3, resulted in 4% haemolysis after 35 days of storage. The ATP content of untreated and treated RBC declined with similar kinetics during storage. CONCLUSION: PDT of RCC with Tri-P(4) for 60 min inactivates a wide range of pathogens, but not cell-associated HIV and a non-enveloped virus, and compromises RBC quality. This reduces the suitability of PDT with Tri-P(4) for red cell sterilization. Therefore, further improvements in the treatment procedures to potentiate pathogen inactivation and to preserve RBC integrity will be required to generate an effective treatment for sterilizing RCC.


Subject(s)
Erythrocytes , Hematoporphyrin Photoradiation/methods , Photosensitizing Agents/pharmacology , Porphyrins/pharmacology , Sterilization/methods , Anti-Bacterial Agents/pharmacology , Antiviral Agents/pharmacology , Blood Preservation/methods , Cell Death , Erythrocyte Transfusion/adverse effects , Erythrocytes/drug effects , Erythrocytes/microbiology , Erythrocytes/virology , Humans , Pseudomonas aeruginosa/drug effects , Staphylococcus aureus/drug effects , Virus Inactivation , Viruses/drug effects , Yersinia enterocolitica/drug effects
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