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Babu B, Mack J, Nyokong T. Photodynamic activity of Sn(IV) tetrathien-2-ylchlorin against MCF-7 breast cancer cells. Dalton Trans 2021; 50:2177-2182. [PMID: 33496304 DOI: 10.1039/d0dt03958f] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A new readily-synthesized Sn(iv) tetraarylchlorin with thien-2-yl substituents (SnC) has been prepared and fully characterized by various spectroscopic techniques and its photophysical and photochemical properties, such as the singlet oxygen quantum yield (ΦΔ), fluorescence quantum yield (ΦF), triplet lifetime (τT) and photostability, have been evaluated. SnC has an unusually high ΦΔ value of 0.89 in DMF. Studies on the photodynamic activity against MCF-7 breast cancer cells exhibited a very low IC50 value of 0.9 μM and high phototoxicity (dark versus light) indices of >27.8 after irradiation with a 660 nm Thorlabs LED (280 mW cm-2). The results demonstrate that Sn(iv) tetraarylchlorins of this type are suitable candidates for further in-depth PDT studies.
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Affiliation(s)
- Balaji Babu
- Institute for Nanotechnology Innovation, Department of Chemistry, Rhodes University, Makhanda 6140, South Africa.
| | - John Mack
- Institute for Nanotechnology Innovation, Department of Chemistry, Rhodes University, Makhanda 6140, South Africa.
| | - Tebello Nyokong
- Institute for Nanotechnology Innovation, Department of Chemistry, Rhodes University, Makhanda 6140, South Africa.
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2
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Dąbrowski JM, Pucelik B, Regiel-Futyra A, Brindell M, Mazuryk O, Kyzioł A, Stochel G, Macyk W, Arnaut LG. Engineering of relevant photodynamic processes through structural modifications of metallotetrapyrrolic photosensitizers. Coord Chem Rev 2016. [DOI: 10.1016/j.ccr.2016.06.007] [Citation(s) in RCA: 123] [Impact Index Per Article: 15.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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3
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van Driel PBAA, Boonstra MC, Slooter MD, Heukers R, Stammes MA, Snoeks TJA, de Bruijn HS, van Diest PJ, Vahrmeijer AL, van Bergen En Henegouwen PMP, van de Velde CJH, Löwik CWGM, Robinson DJ, Oliveira S. EGFR targeted nanobody-photosensitizer conjugates for photodynamic therapy in a pre-clinical model of head and neck cancer. J Control Release 2016; 229:93-105. [PMID: 26988602 PMCID: PMC7116242 DOI: 10.1016/j.jconrel.2016.03.014] [Citation(s) in RCA: 115] [Impact Index Per Article: 14.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2015] [Revised: 03/07/2016] [Accepted: 03/09/2016] [Indexed: 12/21/2022]
Abstract
Photodynamic therapy (PDT) induces cell death through local light activation of a photosensitizer (PS) and has been used to treat head and neck cancers. Yet, common PS lack tumor specificity, which leads to collateral damage to normal tissues. Targeted delivery of PS via antibodies has pre-clinically improved tumor selectivity. However, antibodies have long half-lives and relatively poor tissue penetration, which could limit therapeutic efficacy and lead to long photosensitivity. Here, in this feasibility study, we evaluate at the pre-clinical level a recently introduced format of targeted PDT, which employs nanobodies as targeting agents and a water-soluble PS (IRDye700DX) that is traceable through optical imaging. In vitro, the PS solely binds to cells and induces phototoxicity on cells overexpressing the epidermal growth factor receptor (EGFR), when conjugated to the EGFR targeted nanobodies. To investigate whether this new format of targeted PDT is capable of inducing selective tumor cell death in vivo, PDT was applied on an orthotopic mouse tumor model with illumination at 1h post-injection of the nanobody-PS conjugates, as selected from quantitative fluorescence spectroscopy measurements. In parallel, and as a reference, PDT was applied with an antibody-PS conjugate, with illumination performed 24h post-injection. Importantly, EGFR targeted nanobody-PS conjugates led to extensive tumor necrosis (approx. 90%) and almost no toxicity in healthy tissues, as observed through histology 24h after PDT. Overall, results show that these EGFR targeted nanobody-PS conjugates are selective and able to induce tumor cell death in vivo. Additional studies are now needed to assess the full potential of this approach to improving PDT.
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Affiliation(s)
- Pieter B A A van Driel
- Department of Radiology, Division of Molecular Imaging, Leiden University Medical Center, Albinusdreef 2, 2333 ZA Leiden, The Netherlands; Percuros BV, Drienerlolaan 5, 7522 NB Enschede, The Netherlands
| | - Martin C Boonstra
- Department of Surgery, Leiden University Medical Center, Albinusdreef 2, 2333 ZA Leiden, The Netherlands
| | - Maxime D Slooter
- Department of Radiology, Division of Molecular Imaging, Leiden University Medical Center, Albinusdreef 2, 2333 ZA Leiden, The Netherlands; Percuros BV, Drienerlolaan 5, 7522 NB Enschede, The Netherlands
| | - Raimond Heukers
- Molecular Oncology, Cell Biology Division, Department of Biology, Faculty of Science, Utrecht University, Padualaan 8, 3584 CH Utrecht, The Netherlands
| | - Marieke A Stammes
- Department of Radiology, Division of Molecular Imaging, Leiden University Medical Center, Albinusdreef 2, 2333 ZA Leiden, The Netherlands; Percuros BV, Drienerlolaan 5, 7522 NB Enschede, The Netherlands
| | - Thomas J A Snoeks
- Department of Radiology, Division of Molecular Imaging, Leiden University Medical Center, Albinusdreef 2, 2333 ZA Leiden, The Netherlands
| | - Henriette S de Bruijn
- Department of Otorhinolaryngology & Head and Neck Surgery, Center for Optical Diagnostics and Therapy, Erasmus Medical Center, s-Gravendijkwal 230, 3015 CE Rotterdam, The Netherlands
| | - Paul J van Diest
- Department of Pathology, University Medical Center Utrecht, Heidelberglaan 100, 3584 CX Utrecht, The Netherlands
| | - Alexander L Vahrmeijer
- Department of Surgery, Leiden University Medical Center, Albinusdreef 2, 2333 ZA Leiden, The Netherlands
| | - Paul M P van Bergen En Henegouwen
- Molecular Oncology, Cell Biology Division, Department of Biology, Faculty of Science, Utrecht University, Padualaan 8, 3584 CH Utrecht, The Netherlands
| | - Cornelis J H van de Velde
- Department of Surgery, Leiden University Medical Center, Albinusdreef 2, 2333 ZA Leiden, The Netherlands
| | - Clemens W G M Löwik
- Department of Radiology, Division of Molecular Imaging, Leiden University Medical Center, Albinusdreef 2, 2333 ZA Leiden, The Netherlands
| | - Dominic J Robinson
- Department of Otorhinolaryngology & Head and Neck Surgery, Center for Optical Diagnostics and Therapy, Erasmus Medical Center, s-Gravendijkwal 230, 3015 CE Rotterdam, The Netherlands
| | - Sabrina Oliveira
- Molecular Oncology, Cell Biology Division, Department of Biology, Faculty of Science, Utrecht University, Padualaan 8, 3584 CH Utrecht, The Netherlands.
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Hudson R, Boyle RW. Strategies for selective delivery of photodynamic sensitisers to biological targets. J PORPHYR PHTHALOCYA 2012. [DOI: 10.1142/s1088424604000325] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Strategies for increasing the affinity of photodynamic sensitisers for specific tissues, cells and organisms are reviewed. Biological outcomes are evaluated and therapeutic potential assessed.
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Affiliation(s)
- Robert Hudson
- Photobiology & Photomedicine Group, Department of Chemistry, University of Hull, Cottingham Road, Hull, East Yorkshire HU6 7RX, United Kingdom
| | - Ross W. Boyle
- Photobiology & Photomedicine Group, Department of Chemistry, University of Hull, Cottingham Road, Hull, East Yorkshire HU6 7RX, United Kingdom
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Bullous AJ, Alonso CMA, Boyle RW. Photosensitiser–antibody conjugates for photodynamic therapy. Photochem Photobiol Sci 2011; 10:721-50. [DOI: 10.1039/c0pp00266f] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Savellano MD, Hasan T. Photochemical Targeting of Epidermal Growth Factor Receptor: A Mechanistic Study. Clin Cancer Res 2005; 11:1658-68. [PMID: 15746071 DOI: 10.1158/1078-0432.ccr-04-1902] [Citation(s) in RCA: 74] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
PURPOSE Photoimmunotherapy may allow target-specific photodynamic destruction of malignancies and may also potentiate anticancer antibody therapies. However, clinical use of either of the two modalities is limited for different reasons. Antibody therapies suffer from being primarily cytostatic and the need for prolonged administration with consequent side effects. In the case of photoimmunotherapy, a major impediment has been the absence of well-characterized photosensitizer immunoconjugates (PIC). In this investigation, we suggest a strategy to overcome these limitations and present the successful targeting of epidermal growth factor receptor (EGFR) using a well-characterized PIC. EXPERIMENTAL DESIGN The PIC consisted of the EGFR-recognizing chimeric monoclonal antibody, C225, conjugated with a two-branched polyethylene glycol and benzoporphyrin derivative (BPD, Verteporfin). Mechanistic studies included photophysics, phototoxicity, cellular uptake, and catabolism experiments to yield dosimetric parameters. Target cells included two EGFR-overexpressing human cancer cell lines, OVCAR-5 and A-431. Nontarget cells included an EGFR-negative fibroblast cell line, 3T3-NR6, and a monocyte-macrophage cell line, J774. RESULTS BPD-C225 PICs targeted and photodynamically killed EGFR-overexpressing cells, whereas free BPD exhibited no specificity. On a per mole basis, PICs were less phototoxic than free BPD, but PICs were very selective for target cells, whereas free BPD was not. Phototoxicity of the PICs increased at prolonged incubations. Photodynamic dose calculations indicated that PIC photophysics, photochemistry, catabolism, and subcellular localization were important determinants of PIC phototoxic potency. CONCLUSIONS This study shows the efficacy of EGFR targeting with PIC constructs and suggests approaches to improve PIC designs and targeting strategies for in vivo photoimmunotherapy. The approach offers the possibility of dual effects via antibody-mediated cytostasis and photoimmunotherapy-based cytotoxicity.
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Affiliation(s)
- Mark D Savellano
- Department of Surgery, Dartmouth-Hitchcock Medical Center, Lebanon, NH, USA
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Nyman ES, Hynninen PH. Research advances in the use of tetrapyrrolic photosensitizers for photodynamic therapy. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY B-BIOLOGY 2004; 73:1-28. [PMID: 14732247 DOI: 10.1016/j.jphotobiol.2003.10.002] [Citation(s) in RCA: 555] [Impact Index Per Article: 27.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Photodynamic therapy (PDT) is a promising new treatment modality for several diseases, most notably cancer. In PDT, light, O2, and a photosensitizing drug are combined to produce a selective therapeutic effect. Lately, there has been active research on new photosensitizer candidates, because the most commonly used porphyrin photosensitizers are far from ideal with respect to PDT. Finding a suitable photosensitizer is crucial in improving the efficacy of PDT. Recent synthetic activity has created such a great number of potential photosensitizers for PDT that it is difficult to decide which ones are suitable for which pathological conditions, such as various cancer species. To facilitate the choice of photosensitizer, this review presents a thorough survey of the photophysical and chemical properties of the developed tetrapyrrolic photosensitizers. Special attention is paid to the singlet-oxygen yield (PhiDelta) of each photosensitizer, because it is one of the most important photodynamic parameters in PDT. Also, in the survey, emphasis is placed on those photosensitizers that can easily be prepared by partial syntheses starting from the abundant natural precursors, protoheme and the chlorophylls. Such emphasis is justified by economical and environmental reasons. Several of the most promising photosensitizer candidates are chlorins or bacteriochlorins. Consequently, chlorophyll-related chlorins, whose PhiDelta have been determined, are discussed in detail as potential photosensitizers for PDT. Finally, PDT is briefly discussed as a treatment modality, including its clinical aspects, light sources, targeting of the photosensitizer, and opportunities.
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Affiliation(s)
- Emma S Nyman
- Laboratory of Organic Chemistry, Department of Chemistry, University of Helsinki, P.O. BOX 55 (A.I. Virtasen aukio 1), Helsinki FIN-00014, Finland
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Cavanaugh PG. Synthesis of chlorin e6-transferrin and demonstration of its light-dependent in vitro breast cancer cell killing ability. Breast Cancer Res Treat 2002; 72:117-30. [PMID: 12038702 DOI: 10.1023/a:1014811915564] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
The transferrin receptor is often highly expressed in tumor cells whereas it is usually present at low levels in surrounding normal adult tissue. Here, a potential anti-cancer agent is described, which is directed at this receptor and consists of a toxin-modified transferrin, which is activated via photodynamic therapy. The porphyrin chlorin e6 was conjugated to transferrin using a procedure, which involved the preliminary binding of the protein to quaternary amino ethyl-sephadex. This maintained the natural activity of the transferrin, and the un-activated conjugate exhibited no in vitro cellular toxicity. The conjugate's singlet oxygen yield was estimated by assessment of its light-dependent oxidation of tetramethylbenzidine, where it displayed approximately 70% of the efficiency of native chlorin e6. When chlorin e6-transferrin treated human MCF7 and rat MTLn3 mammary adenocarcinoma cells were exposed to toxin-activating visible light, a tumor cell killing effect was achieved in normal (medium plus 10% FBS) culture conditions with an ED50 of approximately 10-20 microg/ml. A method for the synthesis of chlorin e6-transferrin was developed, and the conjugate was shown to exhibit a light-dependent killing of mammary adenocarcinoma cells in culture. The conjugate demonstrated potential as an anti-cancer agent.
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Strong LH, Berthiaume F, Yarmush ML. Control of fibroblast populated collagen lattice contraction by antibody targeted photolysis of fibroblasts. Lasers Surg Med 2000; 21:235-47. [PMID: 9291080 DOI: 10.1002/(sici)1096-9101(1997)21:3<235::aid-lsm3>3.0.co;2-r] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
BACKGROUND AND OBJECTIVE Hypertrophic scarring and rigid scar contracture are disorders of wound healing for which there is presently no effective therapy. The dermal fibroblast plays a major role in scar fibrillogenesis and contracture. The objective of this study was to establish a selective and effective method to destroy fibroblasts. STUDY DESIGN/MATERIALS AND METHODS An antifibroblast conjugate was synthesized by covalent attachment of the antifibroblast antibody PR2D3 to the photosensitizer Sn-chlorin e6. Fibroblasts were cultured in fibroblast-populated collagen lattices (FPCLs), incubated with the conjugate and exposed to light. The effect of the treatment on cell viability and the rate of contraction of the FPCL were assessed. RESULTS The toxicity of antifibroblast conjugates increased with increasing conjugate concentration, light dose, and number of photosensitizers per antibody molecule, until nearly complete killing was achieved. The rate of lattice contraction after irradiation linearly correlated with the remaining viable fraction of fibroblasts. These conjugates were not cytotoxic to keratinocytes cultured on collagen lattices, and nonspecific conjugates could not cause significant fibroblast killing. Spatial selectivity was demonstrated using a light mask. CONCLUSIONS Antibody-targeted photolysis is an effective and selective technique for controlling FPCL contraction in vitro and may have potential in vivo applications to modulate extracellular matrix remodeling by connective tissue cells.
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Affiliation(s)
- L H Strong
- Center for Engineering in Medicine/Surgical Services, Massachusetts General Hospital, Boston 02114, USA
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Carcenac M, Larroque C, Langlois R, Lier JE, Artus JC, Pelegrin A. Preparation, Phototoxicity and Biodistribution Studies of Anti-Carcinoembryonic Antigen Monoclonal Antibody-Phthalocyanine Conjugates. Photochem Photobiol 1999. [DOI: 10.1111/j.1751-1097.1999.tb08304.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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11
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Redmond RW, Gamlin JN. A Compilation of Singlet Oxygen Yields from Biologically Relevant Molecules. Photochem Photobiol 1999. [DOI: 10.1111/j.1751-1097.1999.tb08240.x] [Citation(s) in RCA: 573] [Impact Index Per Article: 22.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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12
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Busch NA, Yarmush ML, Toner M. A theoretical formalism for aggregation of peroxidized lipids and plasma membrane stability during photolysis. Biophys J 1998; 75:2956-70. [PMID: 9826616 PMCID: PMC1299967 DOI: 10.1016/s0006-3495(98)77737-9] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
The objective of this investigation was to examine, from a theoretical perspective, the mechanism underlying the lysis of plasma membranes by photoinduced, chemically mediated damage such as is found in photolysis. Toward this end, a model is presented which relates the membrane lifetime to the thermodynamic parameters of the membrane components based upon the kinetic theory of aggregate formation. The formalism includes a standard birth/death process for the formation of damaged membrane components (i.e., peroxidized lipids) as well as a terminating condensation process for the formation of aggregates of peroxidized plasma membrane lipids. Our theory predicts that 1) the membrane lifetime is inversely correlated with predicted rate of membrane damage; 2) an upper limit on the duration of membrane damage exists, above which the mean and variance of the membrane lifetime is independent of further membrane damage; and 3) both the mean and variance of the time of membrane lifetime distribution are correlated with the number of sites that may be damaged to form a single membrane defect. The model provides a framework to optimize the lysis of cell membranes by photodynamic therapy.
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Affiliation(s)
- N A Busch
- Center for Engineering in Medicine and Surgical Services, Massachusetts General Hospital, Harvard Medical School, and Shriners Burns Hospital, Boston, Massachusetts 02139 USA
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Busch NA, Reiken SR, Toner M, Yarmush ML. Intracellular calcium dynamics during photolysis. J Biomech Eng 1998; 120:570-8. [PMID: 10412433 DOI: 10.1115/1.2834746] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The objective of this investigation was to gain a deeper understanding of the intracellular events that precede photolysis of cells. A model system, consisting of malignant melanoma cells pretreated with the calcium sensitive fluorescent dye, Fluo-3, was used to examine the intracellular calcium dynamics in single-cell photolysis experiments. Exposure of the cells to 632 nm laser light in the presence of photosensitizer, tin chlorin e6, resulted in a rise in intracellular calcium. The increase in intracellular calcium was blocked using a variety of calcium channel blocking agents, including verapamil, nifedipine, and nickel. Treatment with the channel blockers was also effective in either decreasing or eliminating cell death despite the presence of lethal doses of photosensitizer and irradiation. These results show that intracellular calcium rises prior to plasma membrane lysis, and that this early rise in intracellular calcium is necessary for membrane rupture.
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Affiliation(s)
- N A Busch
- Center for Engineering in Medicine, Massachusetts General Hospital, Boston, USA
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Boch R, Mohtat N, Lear Y, Arnason JT, Durst T, Scaiano JC. Study of photoinduced energy and electron transfer in alpha-terthienyl-bovine serum albumin conjugates: a laser flash photolysis study. Photochem Photobiol 1996; 64:92-9. [PMID: 8787021 DOI: 10.1111/j.1751-1097.1996.tb02426.x] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
The photochemistry of alpha-terthienyl (alpha-T) has been examined in bovine serum albumin (BSA). Freely associated and covalently conjugated alpha-T chromophores show similar behavior toward nonpolar quenchers such as oxygen and benzoquinone but show significant differences in the case of quenching by methyl viologen, a watersoluble cationic electron acceptor; in this case, triplet quenching reveals two distinct alpha-T populations, attributed to chromophores in sites showing very different accessibility from the aqueous phase. Rate constants for triplet quenching in BSA are generally slower than those observed in homogeneous solution for free alpha-T. For example, in the case of oxygen, the rate constant is about one order of magnitude smaller when alpha-T is associated or conjugated with the protein compared with alpha-T in solution. While triplet yields for alpha-T are essentially the same in solution and in the protein environment, the yield of detectable singlet oxygen is substantially reduced in the protein. This is attributed to a geminate reaction within the protein involving singlet oxygen trapping in the vicinity of the generation site.
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Affiliation(s)
- R Boch
- Department of Chemistry, University of Ottawa, Canada
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15
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Thorpe WP, Toner M, Ezzell RM, Tompkins RG, Yarmush ML. Dynamics of photoinduced cell plasma membrane injury. Biophys J 1995; 68:2198-206. [PMID: 7612864 PMCID: PMC1282125 DOI: 10.1016/s0006-3495(95)80402-9] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
We have developed a video microscopy system designed for real-time measurement of single cell damage during photolysis under well defined physicochemical and photophysical conditions. Melanoma cells cultured in vitro were treated with the photosensitizer (PS), tin chlorin e6 (SnCe6) or immunoconjugate (SnCe6 conjugated to a anti-ICAM monoclonal antibody), and illuminated with a 10 mW He/Ne laser at a 630 nm wavelength. Cell membrane integrity was assessed using the vital dye calcein-AM. In experiments in which the laser power density and PS concentration were varied, it was determined that the time lag before cell rupture was inversely proportional to the estimated singlet oxygen flux to the cell surface. Microscopic examination of the lytic event indicated that photo-induced lysis was caused by a point rupture of the plasma membrane. The on-line nature of this microscopy system offers an opportunity to monitor the dynamics of the cell damage process and to gain insights into the mechanism governing photolytic cell injury processes.
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Affiliation(s)
- W P Thorpe
- Department of Chemical and Biochemical Engineering, Rutgers University, Piscataway, New Jersey 08855, USA
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Berthiaume F, Reiken SR, Toner M, Tompkins RG, Yarmush ML. Antibody-targeted photolysis of bacteria in vivo. BIO/TECHNOLOGY (NATURE PUBLISHING COMPANY) 1994; 12:703-6. [PMID: 7764916 DOI: 10.1038/nbt0794-703] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
We have evaluated the efficacy of antibody-targeted photolysis to kill bacteria in vivo using specific antibacterial photosensitizer (PS) immunconjugates. After infecting the dorsal skin in mice with Pseudomonas aeruginosa, both specific and nonspecific tin (IV) chlorin e6-monoclonal antibody conjugates were injected at the infection site. After a 15 min incubation period, the site was exposed to 630 nm light with a power density of 100 mW/cm2 for 1600 seconds. Irradiation resulted in a greater then 75% decrease in the number of viable bacteria at sites treated with a specific conjugate, whereas normal bacterial growth was observed in animals that were untreated or treated with a nonspecific conjugate. Antibody-targeted photolysis may be a selective and versatile tool for treating a variety of infections.
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Affiliation(s)
- F Berthiaume
- Surgical Services, Massachusetts Hospital, Boston
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Bacterial cell killing by antibody targeted photolysis: enhanced effect by OH radical generation. J Control Release 1994. [DOI: 10.1016/0168-3659(94)90164-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Nechaeva IS, Mitina VK, Ponomarev GV, Klyashchitskii BA. Photoimmunotoxins: New targeted-action sensitizers for the photodynamic therapy of tumors (review). Pharm Chem J 1993. [DOI: 10.1007/bf00780543] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Spikes JD, Bommer JC. Photosensitizing properties of mono-L-aspartyl chlorin e6 (NPe6): a candidate sensitizer for the photodynamic therapy of tumors. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY. B, BIOLOGY 1993; 17:135-43. [PMID: 8459317 DOI: 10.1016/1011-1344(93)80006-u] [Citation(s) in RCA: 107] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
There is a large amount of interest in chlorins as photosensitizers for the photodynamic therapy of tumors because of their strong absorption in the red, where light penetration into mammalian tissues is efficient. Mono-L-aspartyl chlorin e6 (NPe6), in phosphate buffer of pH 7.4, had absorption peaks at 400 and 654 nm with molar absorption coefficients of 180,000 and 40,000 M-1 cm-1 respectively. In buffer, the NPe6 triplet had a peak at 440 nm and a lifetime under argon of approximately 300 microseconds. The triplet was efficiently quenched by ground state oxygen (kQ = 1.9 x 10(9) M-1 s-1) with the formation of singlet oxygen, as identified by its near infrared luminescence. The quantum yield of singlet oxygen production was 0.77. A number of substrates were efficiently photo-oxidized by NPe6, including furfuryl alcohol, cysteine, histidine, tryptophan and human serum albumin. These reactions were efficiently inhibited by azide (which did not quench NPe6 triplets), indicating that they are probably mediated by singlet oxygen. Thus, NPe6 has a desirable array of photoproperties for a sensitizer to be used in the clinical photodynamic therapy of tumors.
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Affiliation(s)
- J D Spikes
- Department of Biology, University of Utah, Salt Lake City 84112
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Lu XM, Fischman AJ, Stevens E, Lee TT, Strong L, Tompkins RG, Yarmush ML. Sn-chlorin e6 antibacterial immunoconjugates. An in vitro and in vivo analysis. J Immunol Methods 1992; 156:85-99. [PMID: 1431166 DOI: 10.1016/0022-1759(92)90014-k] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Monoclonal antibody-Sn-chlorin e6 immunoconjugates were prepared by the site-selective covalent modification of the monoclonal oligosaccharide moiety. By carefully controlling the reaction conditions and introducing triethanolamine groups as axial ligands of the Sn moiety, conjugates with in vivo biodistribution properties similar to underivatized IgG were prepared. By varying the reaction conditions, conjugates were reproducibly prepared with a range of photosensitizer to mAb molar ratios from 1.6 to 10. Based on a competitive inhibition radioimmunoassay, conjugates prepared by this method showed selectivity and binding affinity comparable to the unmodified antibody. The immunoconjugates had only slightly lower singlet oxygen yields than that observed with the Sn-chlorin e6 precursor indicating that negligible aggregation or structural modification of the chromophores occurred during the synthesis process. In vitro cell killing experiments demonstrated that all conjugates possessed significant cytotoxic activity. Biodistribution studies in mice showed that conjugates prepared with axial ligands had significant serum retention 24 h after injection while conjugates prepared without the triethanolamine ligand were much more rapidly cleared. In vivo specificity was demonstrated using rats infected with Fisher immunotype I P. aeruginosa at a site in the left posterior thigh muscle. Target to background ratios exceeded 60 at 120 h after conjugate injection of the specific immunoconjugate, compared to a ratio of only 6 for a non-specific mouse IgG conjugate. Biodistribution patterns at 120 h post injection indicate that the conjugates were both biologically active and structurally intact.
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Affiliation(s)
- X M Lu
- Surgical Services, Massachusetts General Hospital, Boston 02114
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