The iron chelators can be utilized in target cells to improve 5-aminolaevulinic acid （ALA）-based photodynamic therapy （PDT）. The purpose of this study is to compare the effect of two kinds of iron chelators, desfe...The iron chelators can be utilized in target cells to improve 5-aminolaevulinic acid （ALA）-based photodynamic therapy （PDT）. The purpose of this study is to compare the effect of two kinds of iron chelators, desferrioxamine （DFO） and ethylenediaminetetraacetic acid （EDTA） on the enhancement of ALA-PDT. HaCat cells were cultured in medium containing 2.0 mmol/L of ALA and 0.5 mmol/L of DFO or EDTA. After 3-h incubation in the dark, the concentration of cellular pro-toporphyrin Ⅸ （PpⅨ） was detected by high performance liquid chromatography （HPLC）, and the fluorescence of PpⅨ was observed at 630 nm emission under confocal laser scanning microscope. For PDT, HaCat cells were irradiated using 632.8 nm laser, and the fractions of apoptotic and necrotic cells were flow cytometrically assayed. Related differences in morphology and ultrastructure of Ha-Cat cells were observed using optical microscope or transmission electron microscope. Compared to incubation with ALA alone, the addition of DFO or EDTA increased the concentration of cellular PpⅨ and the fluorescent density of PpⅨ, and also increased cell death ratio after PDT. PDT using ALA plus DFO produced the highest cellular PpⅨ level, greatest cell death ratio and most severe structural damage to the cells. It was concluded that both DFO and EDTA could enhance ALA-based PpⅨ production and PDT. Compared to the non-specific iron chelator of EDTA, the specific chelator, DFO, showed more potential for the enhancement.展开更多
Vision is one of our most precious senses,and its impairment has a high socio-economic impact.In the industrialized world,degenerative diseases of the retina lead to vision loss,particularly among the elderly.These de...Vision is one of our most precious senses,and its impairment has a high socio-economic impact.In the industrialized world,degenerative diseases of the retina lead to vision loss,particularly among the elderly.These degenerations include,for instance,retinitis pigmentosa,age-related macular degeneration,and diabetic retinopathy.Although treatments are evolving to manage late-stage symptoms of retinal degenerations,no effective therapies to recover vision loss exist.Retinal degeneration often involves loss or damage to specialized neural cells,such as photoreceptors,and their death stimulates the activation and proliferation of Müller cells(Salman et al.,2021).展开更多
Photodynamic therapy(PDT) is a clinically approved procedure for treatment of cancer and infections. PDT involves systemic or topical administration of a photosensitizer(PS), followed by irradiation of the diseased ar...Photodynamic therapy(PDT) is a clinically approved procedure for treatment of cancer and infections. PDT involves systemic or topical administration of a photosensitizer(PS), followed by irradiation of the diseased area with light of a wavelength corresponding to an absorbance band of the PS. In the presence of oxygen, a photochemical reaction is initiated, leading to the generation of reactive oxygen species and cell death. Besides causing direct cytotoxic effects on illuminated tumor cells, PDT is known to cause damage to the tumor vasculature and induce the release of pro-inflammatory molecules. Pre-clinical and clinical studies have demonstrated that PDT is capable of affecting both the innate and adaptive arms of the immune system. Immune stimulatory properties of PDT may increase its beneficial effects giving the therapy wider potential to become more extensively used in clinical practice. Be-sides stimulating tumor-specific cytotoxic T-cells capable to destroy distant untreated tumor cells, PDT leads to development of anti-tumor memory immunity that can potentially prevent the recurrence of cancer. The immunological effects of PDT make the therapy more effective also when used for treatment of bacterial infections, due to an augmented infiltration of neutrophils into the infected regions that seems to potentiate the outcome of the treatment.展开更多
Development of novel vaccine deliveries and vaccine adjuvants is of great importance to address the dilemma that the vaccine field faces:to improve vaccine efficacy without compromising safety.Harnessing the specific ...Development of novel vaccine deliveries and vaccine adjuvants is of great importance to address the dilemma that the vaccine field faces:to improve vaccine efficacy without compromising safety.Harnessing the specific effects of laser on biological systems,a number of novel concepts have been proposed and proved in recent years to facilitate vaccination in a safer and more efficient way.The key advantage of using laser technology in vaccine delivery and adjuvantation is that all processes are initiated by physical e®ects with no foreign chemicals administered into the body.Here,we review the recent advances in using laser technology to facilitate vaccine delivery and augment vaccine efficacy as well as the underlying mechanisms.展开更多
The ability to track individual cells in space over time is crucial to analyzing heterogeneous cell populations.Recently,microlaser particles have emerged as unique optical probes for massively multiplexed single-cell...The ability to track individual cells in space over time is crucial to analyzing heterogeneous cell populations.Recently,microlaser particles have emerged as unique optical probes for massively multiplexed single-cell tagging.However,the microlaser far-field emission is inherently direction-dependent,which causes strong intensity fluctuations when the orientation of the particle varies randomly inside cells.Here,we demonstrate a general solution based on the incorporation of nanoscale light scatterers into microlasers.Two schemes are developed by introducing either boundary defects or a scattering layer into microdisk lasers.The resulting laser output is omnidirectional,with the minimum-to-maximum ratio of the angle-dependent intensity improving from 0.007(-24 dB)to>0.23(-6dB).After transfer into live cells in vitro,the omnidirectional laser particles within moving cells could be tracked continuously with high signal-to-noise ratios for 2 h,while conventional microlasers exhibited frequent signal loss causing tracking failure.展开更多
Biomolecular analysis at the single-cell level is increasingly important in the study of cellular heterogeneity and its consequences,particularly in organismic development and complex diseases such as cancer.Single-ce...Biomolecular analysis at the single-cell level is increasingly important in the study of cellular heterogeneity and its consequences,particularly in organismic development and complex diseases such as cancer.Single-cell molecular analyses have led to the identification of new cell types1 and the discovery of novel targets for diagnosis and therapy2.While these analyses are performed predominantly on dissociated single cells,emerging techniques seek understanding of cellular state,cellular function and cell–cell interactions within the native tissue environment by combining optical microscopy and single-cell molecular analyses.These techniques include in situ multiplexed imaging of fluorescently labeled proteins and nucleotides,as well as low-throughput ex vivo methods in which specific cells are isolated for downstream molecular analyses.However,these methods are limited in either the number and type of molecular species they can identify or the number of cells that can be analyzed.High-throughput methods are needed for comprehensive profiling of many cells(>1000)to detect rare cell types,discriminate relevant biomarkers from intrinsic population noise,and reduce the time and cost of measurement.Many established,highthroughput single-cell analyses are not directly applicable because they require tissue dissociation,leading to a loss of spatial information3.No current methods exist that can seamlessly connect spatial mapping to single-cell techniques.In this Perspective,we review current methods for spatially resolved single-cell analysis and discuss the prospect of novel multiplexed imaging probes,called laser particles,which allow individual cells to be tagged in tissue and analyzed subsequently using high-throughput,comprehensive single-cell techniques.展开更多
Corner cube retroreflectors(CCRs)have applications in sensors,image processing,free space communication and wireless networks.The ability to construct low-loss wavelength filters embedded in CCRs can enable the develo...Corner cube retroreflectors(CCRs)have applications in sensors,image processing,free space communication and wireless networks.The ability to construct low-loss wavelength filters embedded in CCRs can enable the development of wavelength multiplexing,tunable lasers and photonic integrated circuits.Here we created an~10-μm-thick holographic corner cube retroreflector(HCCR)array that acted as a color-selective wavelength filter and diffracted light at broad angles.Angle-resolved spectral measurements showed that the Bragg peak of the diffracted light from the HCCR array could be tuned from 460 to 545 nm by varying the incident angle.The HCCR array also exhibited a wavelength-selective tuning capability based on the rotation angle in the visible spectrum.HCCRs projected holographic images with the rotational property in the far field.The utility of the HCCR was demonstrated as optical temperature and relative humidity sensors that produced a visible colorimetric response for rapid diagnostics.展开更多
Despite decades of efforts,state-of-the-art synthetic burn dressings to treat partial-thickness burns are still far from ideal.Current dressings adhere to the wound and necessitate debridement.This work describes the ...Despite decades of efforts,state-of-the-art synthetic burn dressings to treat partial-thickness burns are still far from ideal.Current dressings adhere to the wound and necessitate debridement.This work describes the first“supramolecular hybrid hydrogel(SHH)”burn dressing that is biocompatible,self-healable,and on-demand dissoluble for easy and trauma-free removal,prepared by a simple,fast,and scalable method.These SHHs leverage the interactions of a custom-designed cationic copolymer via host-guest chemistry with cucurbit[7]uril and electrostatic interactions with clay nanosheets coated with an anionic polymer to achieve enhanced mechanical properties and fast on-demand dissolution.The SHHs show high mechanical strength(>50 kPa),self-heal rapidly in~1 min,and dissolve quickly(4-6 min)using an amantadine hydrochloride(AH)solution that breaks the supramolecular interactions in the SHHs.Neither the SHHs nor the AH solution has any adverse effects on human dermal fibroblasts or epidermal keratinocytes in vitro.The SHHs also do not elicit any significant cytokine response in vitro.Furthermore,in vivo murine experiments show no immune or inflammatory cell infiltration in the subcutaneous tissue and no change in circulatory cytokines compared to sham controls.Thus,these SHHs present excellent burn dressing candidates to reduce the time of pain and time associated with dressing changes.展开更多
Background:Epidermal stem cells(EpSCs)that reside in cutaneous hair follicles and the basal layer of the epidermis are indispensable for wound healing and skin homeostasis.Little is known about the effects of photoche...Background:Epidermal stem cells(EpSCs)that reside in cutaneous hair follicles and the basal layer of the epidermis are indispensable for wound healing and skin homeostasis.Little is known about the effects of photochemical activation on EpSC differentiation,proliferation and migration during wound healing.The present study aimed to determine the effects of photodynamic therapy(PDT)on wound healing in vivo and in vitro.Methods:We created mouse full-thickness skin resection models and applied 5-aminolevulinic acid(ALA)for PDT to the wound beds.Wound healing was analysed by gross evaluation and haematoxylin–eosin staining in vivo.In cultured EpSCs,protein expression was measured using flow cytometry and immunohistochemistry.Cell migration was examined using a scratch model;apoptosis and differentiation were measured using flow cytometry.Results:PDT accelerated wound closure by enhancing EpSC differentiation,proliferation and migration,thereby promoting re-epithelialization and angiogenesis.PDT inhibited inflammatory infiltration and expression of proinflammatory cytokines,whereas the secretion of growth factors was greater than in other groups.The proportion of transient amplifying cells was significantly greater in vivo and in vitro in the PDT groups.EpSC migration was markedly enhanced after ALAinduced PDT.Conclusions:Topical ALA-induced PDT stimulates wound healing by enhancing re-epithelialization,promoting angiogenesis as well as modulating skin homeostasis.This work provides a preliminary theoretical foundation for the clinical administration of topical ALA-induced PDT in skin wound healing.展开更多
The significance and ability for receptor targeted nanoliposomes(tNLs)to bind to their molecular targets in solid tumors in vivo has been questioned,particularly as the efficiency of their tumor accumulation and selec...The significance and ability for receptor targeted nanoliposomes(tNLs)to bind to their molecular targets in solid tumors in vivo has been questioned,particularly as the efficiency of their tumor accumulation and selectivity is not always predictive of their efficacy or molecular specificity.This study presents,for the first time,in situ near-infrared(NIR)molecular imaging-based quantitation of the in vivo specificity of tNLs for their target receptors,as opposed to tumor selectivity,which includes influences of enhanced tumor permeability and retention.Results show that neither tumor delivery nor selectivity(tumor-to-normal ratio)of cetuximab and IRDye conjugated tNLs correlate with epidermal growth factor receptor(EGFR)expression in U251,U87,and 9L tumors,and in fact underrepresent their imaging-derived molecular specificity by up to 94.2%.Conversely,their in vivo specificity,which we quantify as the concentration of tNL-reported tumor EGFR provided by NIR molecular imaging,correlates positively with EGFR expression levels in vitro and ex vivo(Pearson’s r=0.92 and 0.96,respectively).This study provides a unique opportunity to address the problematic disconnect between tNL synthesis and in vivo specificity.The findings encourage their continued adoption as platforms for precision medicine,and facilitates intelligent synthesis and patient customization in order to improve safety profiles and therapeutic outcomes.展开更多
文摘The iron chelators can be utilized in target cells to improve 5-aminolaevulinic acid （ALA）-based photodynamic therapy （PDT）. The purpose of this study is to compare the effect of two kinds of iron chelators, desferrioxamine （DFO） and ethylenediaminetetraacetic acid （EDTA） on the enhancement of ALA-PDT. HaCat cells were cultured in medium containing 2.0 mmol/L of ALA and 0.5 mmol/L of DFO or EDTA. After 3-h incubation in the dark, the concentration of cellular pro-toporphyrin Ⅸ （PpⅨ） was detected by high performance liquid chromatography （HPLC）, and the fluorescence of PpⅨ was observed at 630 nm emission under confocal laser scanning microscope. For PDT, HaCat cells were irradiated using 632.8 nm laser, and the fractions of apoptotic and necrotic cells were flow cytometrically assayed. Related differences in morphology and ultrastructure of Ha-Cat cells were observed using optical microscope or transmission electron microscope. Compared to incubation with ALA alone, the addition of DFO or EDTA increased the concentration of cellular PpⅨ and the fluorescent density of PpⅨ, and also increased cell death ratio after PDT. PDT using ALA plus DFO produced the highest cellular PpⅨ level, greatest cell death ratio and most severe structural damage to the cells. It was concluded that both DFO and EDTA could enhance ALA-based PpⅨ production and PDT. Compared to the non-specific iron chelator of EDTA, the specific chelator, DFO, showed more potential for the enhancement.
文摘Vision is one of our most precious senses,and its impairment has a high socio-economic impact.In the industrialized world,degenerative diseases of the retina lead to vision loss,particularly among the elderly.These degenerations include,for instance,retinitis pigmentosa,age-related macular degeneration,and diabetic retinopathy.Although treatments are evolving to manage late-stage symptoms of retinal degenerations,no effective therapies to recover vision loss exist.Retinal degeneration often involves loss or damage to specialized neural cells,such as photoreceptors,and their death stimulates the activation and proliferation of Müller cells(Salman et al.,2021).
基金Supported by United States National Institute of Health grant AI050875the Ph D program of the Medical University of Graz,Austria
文摘Photodynamic therapy(PDT) is a clinically approved procedure for treatment of cancer and infections. PDT involves systemic or topical administration of a photosensitizer(PS), followed by irradiation of the diseased area with light of a wavelength corresponding to an absorbance band of the PS. In the presence of oxygen, a photochemical reaction is initiated, leading to the generation of reactive oxygen species and cell death. Besides causing direct cytotoxic effects on illuminated tumor cells, PDT is known to cause damage to the tumor vasculature and induce the release of pro-inflammatory molecules. Pre-clinical and clinical studies have demonstrated that PDT is capable of affecting both the innate and adaptive arms of the immune system. Immune stimulatory properties of PDT may increase its beneficial effects giving the therapy wider potential to become more extensively used in clinical practice. Be-sides stimulating tumor-specific cytotoxic T-cells capable to destroy distant untreated tumor cells, PDT leads to development of anti-tumor memory immunity that can potentially prevent the recurrence of cancer. The immunological effects of PDT make the therapy more effective also when used for treatment of bacterial infections, due to an augmented infiltration of neutrophils into the infected regions that seems to potentiate the outcome of the treatment.
基金This work is supported in part by the National Institutes of Health grants AI089779,AI070785,AI097696 and DA028378 (to M.X.W.)the National Institutes of Health grants DA033371,AI107678 (to X.Y.C).
文摘Development of novel vaccine deliveries and vaccine adjuvants is of great importance to address the dilemma that the vaccine field faces:to improve vaccine efficacy without compromising safety.Harnessing the specific effects of laser on biological systems,a number of novel concepts have been proposed and proved in recent years to facilitate vaccination in a safer and more efficient way.The key advantage of using laser technology in vaccine delivery and adjuvantation is that all processes are initiated by physical e®ects with no foreign chemicals administered into the body.Here,we review the recent advances in using laser technology to facilitate vaccine delivery and augment vaccine efficacy as well as the underlying mechanisms.
基金supported by the National Key R&D Program of China(2018YFB1107200)the National Natural Science Foundation of China(NSFC)(Grants 62075084,61522504,61420106014,11734012,and 11574218)+3 种基金the Guangdong Provincial Innovation and Entrepreneurship Project(Grant 2016ZT06D081)the Guangdong Basic and Applied Basic Research Foundation(2020A1515010615)the Fundamental Research Funds for the Central Universities(21620415)the China Scholarship Council(201906785011).
文摘The ability to track individual cells in space over time is crucial to analyzing heterogeneous cell populations.Recently,microlaser particles have emerged as unique optical probes for massively multiplexed single-cell tagging.However,the microlaser far-field emission is inherently direction-dependent,which causes strong intensity fluctuations when the orientation of the particle varies randomly inside cells.Here,we demonstrate a general solution based on the incorporation of nanoscale light scatterers into microlasers.Two schemes are developed by introducing either boundary defects or a scattering layer into microdisk lasers.The resulting laser output is omnidirectional,with the minimum-to-maximum ratio of the angle-dependent intensity improving from 0.007(-24 dB)to>0.23(-6dB).After transfer into live cells in vitro,the omnidirectional laser particles within moving cells could be tracked continuously with high signal-to-noise ratios for 2 h,while conventional microlasers exhibited frequent signal loss causing tracking failure.
基金US National Institutes of Health(DP1-OD022296,P41-EB015903,R01-CA192878)Human Frontier Science Program(RGP0034/2016)MGH Research Scholar Program.
文摘Biomolecular analysis at the single-cell level is increasingly important in the study of cellular heterogeneity and its consequences,particularly in organismic development and complex diseases such as cancer.Single-cell molecular analyses have led to the identification of new cell types1 and the discovery of novel targets for diagnosis and therapy2.While these analyses are performed predominantly on dissociated single cells,emerging techniques seek understanding of cellular state,cellular function and cell–cell interactions within the native tissue environment by combining optical microscopy and single-cell molecular analyses.These techniques include in situ multiplexed imaging of fluorescently labeled proteins and nucleotides,as well as low-throughput ex vivo methods in which specific cells are isolated for downstream molecular analyses.However,these methods are limited in either the number and type of molecular species they can identify or the number of cells that can be analyzed.High-throughput methods are needed for comprehensive profiling of many cells(>1000)to detect rare cell types,discriminate relevant biomarkers from intrinsic population noise,and reduce the time and cost of measurement.Many established,highthroughput single-cell analyses are not directly applicable because they require tissue dissociation,leading to a loss of spatial information3.No current methods exist that can seamlessly connect spatial mapping to single-cell techniques.In this Perspective,we review current methods for spatially resolved single-cell analysis and discuss the prospect of novel multiplexed imaging probes,called laser particles,which allow individual cells to be tagged in tissue and analyzed subsequently using high-throughput,comprehensive single-cell techniques.
基金the Leverhulme TrustWellcome Trust for research funding.
文摘Corner cube retroreflectors(CCRs)have applications in sensors,image processing,free space communication and wireless networks.The ability to construct low-loss wavelength filters embedded in CCRs can enable the development of wavelength multiplexing,tunable lasers and photonic integrated circuits.Here we created an~10-μm-thick holographic corner cube retroreflector(HCCR)array that acted as a color-selective wavelength filter and diffracted light at broad angles.Angle-resolved spectral measurements showed that the Bragg peak of the diffracted light from the HCCR array could be tuned from 460 to 545 nm by varying the incident angle.The HCCR array also exhibited a wavelength-selective tuning capability based on the rotation angle in the visible spectrum.HCCRs projected holographic images with the rotational property in the far field.The utility of the HCCR was demonstrated as optical temperature and relative humidity sensors that produced a visible colorimetric response for rapid diagnostics.
基金This research was supported partially by grants from the National Institutes of Health(NIH 5R21GM136002,NIH 1R21GM141683,and NIH 5R01HL145031)National Science Foundation(NSF Grant CHE-1904465 and EEC-1941543)a Massachusetts General Hospital(MGH)Executive Committee on Research(ECOR)Interim Support Fund,and a Shriners Hospital Research Grant(SHC 85125,and 85128).
文摘Despite decades of efforts,state-of-the-art synthetic burn dressings to treat partial-thickness burns are still far from ideal.Current dressings adhere to the wound and necessitate debridement.This work describes the first“supramolecular hybrid hydrogel(SHH)”burn dressing that is biocompatible,self-healable,and on-demand dissoluble for easy and trauma-free removal,prepared by a simple,fast,and scalable method.These SHHs leverage the interactions of a custom-designed cationic copolymer via host-guest chemistry with cucurbit[7]uril and electrostatic interactions with clay nanosheets coated with an anionic polymer to achieve enhanced mechanical properties and fast on-demand dissolution.The SHHs show high mechanical strength(>50 kPa),self-heal rapidly in~1 min,and dissolve quickly(4-6 min)using an amantadine hydrochloride(AH)solution that breaks the supramolecular interactions in the SHHs.Neither the SHHs nor the AH solution has any adverse effects on human dermal fibroblasts or epidermal keratinocytes in vitro.The SHHs also do not elicit any significant cytokine response in vitro.Furthermore,in vivo murine experiments show no immune or inflammatory cell infiltration in the subcutaneous tissue and no change in circulatory cytokines compared to sham controls.Thus,these SHHs present excellent burn dressing candidates to reduce the time of pain and time associated with dressing changes.
基金supported by National Natural Science Foundation of China(grant No.81571902,31872742).
文摘Background:Epidermal stem cells(EpSCs)that reside in cutaneous hair follicles and the basal layer of the epidermis are indispensable for wound healing and skin homeostasis.Little is known about the effects of photochemical activation on EpSC differentiation,proliferation and migration during wound healing.The present study aimed to determine the effects of photodynamic therapy(PDT)on wound healing in vivo and in vitro.Methods:We created mouse full-thickness skin resection models and applied 5-aminolevulinic acid(ALA)for PDT to the wound beds.Wound healing was analysed by gross evaluation and haematoxylin–eosin staining in vivo.In cultured EpSCs,protein expression was measured using flow cytometry and immunohistochemistry.Cell migration was examined using a scratch model;apoptosis and differentiation were measured using flow cytometry.Results:PDT accelerated wound closure by enhancing EpSC differentiation,proliferation and migration,thereby promoting re-epithelialization and angiogenesis.PDT inhibited inflammatory infiltration and expression of proinflammatory cytokines,whereas the secretion of growth factors was greater than in other groups.The proportion of transient amplifying cells was significantly greater in vivo and in vitro in the PDT groups.EpSC migration was markedly enhanced after ALAinduced PDT.Conclusions:Topical ALA-induced PDT stimulates wound healing by enhancing re-epithelialization,promoting angiogenesis as well as modulating skin homeostasis.This work provides a preliminary theoretical foundation for the clinical administration of topical ALA-induced PDT in skin wound healing.
基金This work was supported by the National Institutes of Health(Nos.K99CA215301 and R00CA215301 to G.O.,No.R37CA212187 to K.S.,and Nos.P01CA084203,R01CA156177,R01CA160998,S10ODO1232601,and R21CA220143 to T.H.)the Bullock-Wellman Fellowship(G.O.),Science Foundation Ireland and the Irish Research Council(S.C.),the American Society of Lasers in Surgery and Medicine Research Grant(S.M.).
文摘The significance and ability for receptor targeted nanoliposomes(tNLs)to bind to their molecular targets in solid tumors in vivo has been questioned,particularly as the efficiency of their tumor accumulation and selectivity is not always predictive of their efficacy or molecular specificity.This study presents,for the first time,in situ near-infrared(NIR)molecular imaging-based quantitation of the in vivo specificity of tNLs for their target receptors,as opposed to tumor selectivity,which includes influences of enhanced tumor permeability and retention.Results show that neither tumor delivery nor selectivity(tumor-to-normal ratio)of cetuximab and IRDye conjugated tNLs correlate with epidermal growth factor receptor(EGFR)expression in U251,U87,and 9L tumors,and in fact underrepresent their imaging-derived molecular specificity by up to 94.2%.Conversely,their in vivo specificity,which we quantify as the concentration of tNL-reported tumor EGFR provided by NIR molecular imaging,correlates positively with EGFR expression levels in vitro and ex vivo(Pearson’s r=0.92 and 0.96,respectively).This study provides a unique opportunity to address the problematic disconnect between tNL synthesis and in vivo specificity.The findings encourage their continued adoption as platforms for precision medicine,and facilitates intelligent synthesis and patient customization in order to improve safety profiles and therapeutic outcomes.
