MgSiO3 Fiber Membrane Scaffold with Triggered Drug Delivery for Osteosarcoma Synergetic Therapy and Bone Regeneration

In this research, a novel MgSiO3 fiber membrane (MSFM) loaded with indocyanine green (ICG) and doxorubicin (DOX) was prepared. Because of MgSiO3's unique lamellar structure composed of a silicon-oxygen tetrahedron, magnesium ion (Mg2+) moves easily and can be further replaced with other cations. Therefore, because of the positively charged functional group of ICG, MSFM has a rather high drug loading for ICG. In addition, there is electrostatic attraction between DOX (a cationic drug) and ICG (an anionic drug). Hence, after loading ICG, more DOX can be adsorbed into MSFM because of electrostatic interaction. The ICG endows the MSFM outstanding photothermal therapy (PTT) performance, and DOX as a chemotherapeutic drug can restrain tumor growth. On the one hand, H+ exchanged with the positively charged DOX based on the MgSiO3 special lamellar structure. On the other hand, the thermal effect could break the electrostatic interaction between ICG and DOX. Based on the above two points, both tumor acidic microenvironment and photothermal effect can trigger DOX release. What's more, in vitro and in vivo antiosteosarcoma therapy evaluations displayed a superior synergetic PTT-chemotherapy anticancer treatment and excellent biocompatibility of DOX&ICG-MSFM. Finally, the MSFM was proven to greatly promote cell proliferation, differentiation, and bone regeneration performance in vitro and in vivo. Therefore, MSFM provides a creative perspective in the design of multifunctional scaffolds and shows promising applications in controlled drug delivery, antitumor performance, and osteogenesis.

Development of Indocyanine Green/Methyl-β-cyclodextrin Complex-Loaded Liposomes for Enhanced Photothermal Cancer Therapy

Photothermal therapy (PTT) is a promising cancer therapeutic approach due to its spatial selectivity and high potency. Indocyanine green (ICG) has been considered a biocompatible PTT agent. However, ICG has several challenges to hinder its clinical use including rapid blood clearance and instability to heat, light, and solvent, leading to a loss of photoactivation property and PTT efficacy. Herein, we leveraged stabilizing components, methyl-β-cyclodextrin and liposomes, in one nanoplatform (ICD lipo) to enhance ICG stability and the photothermal therapeutic effect against cancer. Compared to ICG, ICD lipo displayed a 4.8-fold reduction in degradation in PBS solvent after 30 days and a 3.4-fold reduction in photobleaching after near-infrared laser irradiation. Moreover, in tumor-bearing mice, ICD lipo presented a 2.7-fold increase in tumor targetability and inhibited tumor growth 9.6 times more effectively than did ICG without any serious toxicity. We believe that ICD lipo could be a potential PTT agent for cancer therapeutics.

Expanded ROS Generation and Hypoxia Reversal: Excipient-free Self-assembled Nanotheranostics for Enhanced Cancer Photodynamic Immunotherapy

The efficacy of photodynamic therapy (PDT)-related cancer therapies is significantly restricted by two irreconcilable obstacles, i.e., low reactive oxygen species (ROS) generation capability and hypoxia which constrains the immune response. Herein, this work develops a self-assembled clinical photosensitizer indocyanine green (ICG) and the HSP90 inhibitor 17-dimethylaminoethylamino-17-demethoxygeldanamycin (17-DMAG) nanoparticles (ISDN) without any excipient. This work discovers that the hydrophobic interaction forces between ICG and 17-DMAG promote the photostability of ICG and its intersystem crossing (ISC) process, thereby improving the ROS quantum yield from 0.112 to 0.46. Augmented ROS generation enhances PDT efficacy and further enhances immunogenic cell death (ICD) effects. 17-DMAG inhibits the HSP90/hypoxia-inducible factor 1α (HIF-1α) axis to dramatically reverse the immunosuppressive tumor microenvironment caused by PDT-aggravated hypoxia. In a mouse model of pancreatic cancer, ISDN markedly improve cytotoxic T lymphocyte infiltration and MHC I and MHC II activation, demonstrating the superior ICD effects in situ tumor and the powerful systematic antitumor immunity generation, eventually achieving vigorous antitumor and recurrence resistance. This study proposes an unsophisticated and versatile strategy to significantly improve PDT efficacy for enhancing systemic antitumor immunity and potentially extending it to multiple cancers.

Potentiating dual-directional immunometabolic regulation with nanomedicine to enhance anti-tumor immunotherapy following incomplete photothermal ablation

Photothermal therapy (PTT) is a promising cancer treatment method due to its ability to induce tumor-specific T cell responses and enhance therapeutic outcomes. However, incomplete PTT can leave residual tumors that often lead to new metastases and decreased patient survival in clinical scenarios. This is primarily due to the release of ATP, a damage-associated molecular pattern that quickly transforms into the immunosuppressive metabolite adenosine by CD39, prevalent in the tumor microenvironment, thus promoting tumor immune evasion. This study presents a photothermal nanomedicine fabricated by electrostatic adsorption among the Fe-doped polydiaminopyridine (Fe-PDAP), indocyanine green (ICG), and CD39 inhibitor sodium polyoxotungstate (POM-1). The constructed Fe-PDAP@ICG@POM-1 (FIP) can induce tumor PTT and immunogenic cell death when exposed to a near-infrared laser. Significantly, it can inhibit the ATP-adenosine pathway by dual-directional immunometabolic regulation, resulting in increased ATP levels and decreased adenosine synthesis, which ultimately reverses the immunosuppressive microenvironment and increases the susceptibility of immune checkpoint blockade (aPD-1) therapy. With the aid of aPD-1, the dual-directional immunometabolic regulation strategy mediated by FIP can effectively suppress/eradicate primary and distant tumors and evoke long-term solid immunological memory. This study presents an immunometabolic control strategy to offer a salvage option for treating residual tumors following incomplete PTT.

Dual pH- and ATP-Responsive Antibacterial Nanospray: On-Demand Release of Antibacterial Factors, Imaging Monitoring, and Accelerated Healing of Bacteria-Infected Wounds under NIR Activation

The prevalence of pathogenic bacterial infections with high morbidity and mortality poses a widespread challenge to the healthcare system. Therefore, it is imperative to develop nanoformulations capable of adaptively releasing antimicrobial factors and demonstrating multimodal synergistic antimicrobial activity. Herein, an NIR-activated multifunctional synergistic antimicrobial nanospray MXene/ZIF-90@ICG was prepared by incorporating ZIF-90@ICG nanoparticles onto MXene-NH2 nanosheets. MXene/ZIF-90@ICG can on-demand release the antimicrobial factors MXenes, ICG, and Zn2+ in response to variations in pH and ATP levels within the bacterial infection microenvironment. Under NIR radiation, the combination of MXenes, Zn2+, and ICG generated a significant amount of ROS and elevated heat, thereby enhancing the antimicrobial efficacy of PDT and PTT. Meanwhile, NIR excitation could accelerate the further release of ICG and Zn2+, realizing the multimodal synergistic antibacterial effect of PDT/PTT/Zn2+. Notably, introducing MXenes improved the dispersion of the synthesized antimicrobial nanoparticles in aqueous solution, rendering MXene/ZIF-90@ICG a candidate for application as a nanospray. Importantly, MXene/ZIF-90@ICG demonstrated antimicrobial activity and accelerated wound healing in the constructed in vivo subcutaneous Staphylococcus aureus infection model with NIR activation, maintaining a favorable biosafety level. Therefore, MXene/ZIF-90@ICG holds promise as an innovative nanospray for adaptive multimodal synergistic and efficient antibacterial applications with NIR activation.

Tumor Cell-Targeting and Tumor Microenvironment-Responsive Nanoplatforms for the Multimodal Imaging-Guided Photodynamic/Photothermal/Chemodynamic Treatment of Cervical Cancer

Purpose

Phototherapy, known for its high selectivity, few side effects, strong controllability, and synergistic enhancement of combined treatments, is widely used in treating diseases like cervical cancer.

Methods

In this study, hollow mesoporous manganese dioxide was used as a carrier to construct positively charged, poly(allylamine hydrochloride)-modified nanoparticles (NPs). The NP was efficiently loaded with the photosensitizer indocyanine green (ICG) via the addition of hydrogen phosphate ions to produce a counterion aggregation effect. HeLa cell membrane encapsulation was performed to achieve the final M-HMnO2@ICG NP. In this structure, the HMnO2 carrier responsively degrades to release ICG in the tumor microenvironment, self-generates O2 for sensitization to ICG-mediated photodynamic therapy (PDT), and consumes GSH to expand the oxidative stress therapeutic effect [chemodynamic therapy (CDT) + PDT]. The ICG accumulated in tumor tissues exerts a synergistic PDT/photothermal therapy (PTT) effect through single laser irradiation, improving efficiency and reducing side effects. The cell membrane encapsulation increases nanomedicine accumulation in tumor tissues and confers an immune evasion ability. In addition, high local temperatures induced by PTT can enhance CDT. These properties of the NP enable full achievement of PTT/PDT/CDT and targeted effects.

Results

Mn2+ can serve as a magnetic resonance imaging agent to guide therapy, and ICG can be used for photothermal and fluorescence imaging. After its intravenous injection, M-HMnO2@ICG accumulated effectively at mouse tumor sites; the optimal timing of in-vivo laser treatment could be verified by near-infrared fluorescence, magnetic resonance, and photothermal imaging. The M-HMnO2@ICG NPs had the best antitumor effects among treatment groups under near-infrared light conditions, and showed good biocompatibility.

Conclusion

In this study, we designed a nano-biomimetic delivery system that improves hypoxia, responds to the tumor microenvironment, and efficiently loads ICG. It provides a new economical and convenient strategy for synergistic phototherapy and CDT for cervical cancer.

Near-Infrared Light-Triggered NO Nanogenerator for Gas-Enhanced Photodynamic Therapy and Low-Temperature Photothermal Therapy to Eliminate Biofilms

Purpose

Owing to its noninvasive nature, broad-spectrum effectiveness, minimal bacterial resistance, and high efficiency, phototherapy has significant potential for antibiotic-free antibacterial interventions and combating antibacterial biofilms. However, finding effective strategies to mitigate the detrimental effects of excessive temperature and elevated concentrations of reactive oxygen species (ROS) remains a pressing issue that requires immediate attention.

Methods

In this study, we designed a pH-responsive cationic polymer sodium nitroside dihydrate/branched polyethylenimine-indocyanine green@polyethylene glycol (SNP/PEI-ICG@PEG) nanoplatform using the electrostatic adsorption method and Schiff's base reaction. Relevant testing techniques were applied to characterize and analyze SNP/PEI-ICG@PEG, proving the successful synthesis of the nanomaterials. In vivo and in vitro experiments were performed to evaluate the antimicrobial properties of SNP/PEI-ICG@PEG.

Results

The morphology and particle size of SNP/PEI-ICG@PEG were observed via TEM. The zeta potential and UV-visible (UV-vis) results indicated the synthesis of the nanomaterials. The negligible cytotoxicity of up to 1 mg/mL of SNP/PEI-ICG@PEG in the presence or absence of light demonstrated its biosafety. Systematic in vivo and in vitro antimicrobial assays confirmed that SNP/PEI-ICG@PEG had good water solubility and biosafety and could be activated by near-infrared (NIR) light and synergistically treated using four therapeutic modes, photodynamic therapy (PDT), gaseous therapy (GT), mild photothermal therapy (PTT, 46 °C), and cation. Ultimately, the development of Gram-positive (G+) Staphylococcus aureus (S. aureus) and Gram-negative (G-) Escherichia coli (E. coli) were both completely killed in the free state, and the biofilm that had formed was eliminated.

Conclusion

SNP/PEI-ICG@PEG demonstrated remarkable efficacy in achieving controlled multimodal synergistic antibacterial activity and biofilm infection treatment. The nanoplatform thus holds promise for future clinical applications.

Feasibility and efficacy of indocyanine green in monitoring systemic drug leakage during isolated limb perfusion for recurrent melanoma of extremity

Melanoma is known for its high metastatic potential and aggressive growth. Recurrence is common post-surgery, sometimes leading to unresectable disease. Locally recurrent unresectable melanoma of extremity has been treated with high-dose anticancer chemotherapy via isolated limb perfusion (ILP) to improve local efficacy of drug and salvage limbs. Standard ILP monitoring uses radiolabeled dyes, requiring specialized personnel and involving radiation exposure. In this case, we used indocyanine green (ICG) to track systemic drug leakage during ILP. A 47-year-old gentleman with recurrent malignant melanoma of the left foot, operated twice earlier and treated with adjuvant pembrolizumab, presented with multiple in-transit metastases in the limb. ILP was planned, with 5 mg ICG administered in the perfusion solution along with high-dose melphalan. Stryker's SPI PHI handheld device was employed to visualize ICG during ILP. Absence of fluorescence beyond the involved extremity, such as fingers, ears, and the abdominal wall, indicated no systemic drug dispersion. For control, technetium radiocolloid dye was co-administered, monitored by a precordial gamma probe, confirming no systemic leakage, and validating effectiveness of ICG in leakage monitoring. ICG proves to be a safe, reliable, cost-effective, radiation-free approach for precise systemic drug leakage monitoring during ILP for recurrent melanoma of extremity.

Indocyanine green-mediated fabrication of urchin-like hydroxyethyl starch nanocarriers for enhanced drug tumor EPR and deep penetration effects

Effective EPR and tumor penetration are bottlenecks in current nanomedicine therapy. Comosol software was utilized to analyze the motion process of nanoparticles (NPs) with different shapes, from blood vessels to tumor tissue, to address this. By calculation, urchin-like NPs experienced higher drag forces than spherical NPs, facilitating their EPR and tumor penetration effects. Thus, urchin-like indocyanine green-loaded hydroxyethyl starch-cholesterol (ICG@HES-CH) NPs were prepared by leveraging the instability of ICG responding to near-infrared light (NIR). Upon NIR exposure, ICG degraded and partly disintegrated ICG@HES-CH NPs, and its morphology transformed from spherical to urchin-like. Vincristine (VC), as a model drug, was loaded in urchin-like ICG@HES-CH NPs for the treatment of lymphoma. A20 lymphoma cells and 3T3-A20 tumor organoids were employed to investigate the influence of shape on NPs' cellular uptake, penetration pathway, and cytotoxicity. It demonstrated that urchin-like ICG@HES-CH NPs mainly transport across the extracellular matrix through intercellular pathways, easily reaching the deep tumor sites and achieving higher cytotoxicity. In vivo VC distribution and anti-tumor results indicated that urchin-like NPs increased VC EPR and penetration ability, lowering VC neurotoxicity and superior anti-tumor effect. Therefore, urchin-like ICG@HES-CH NPs have great translational potential to be used as chemotherapeutic nanocarriers in anticancer therapy.

Amino acid-based metallo-supramolecular nanoassemblies capable of regulating cellular redox homeostasis for tumoricidal chemo-/photo-/catalytic combination therapy

Nanozymes, as nanomaterials with natural enzyme activities, have been widely applied to deliver various therapeutic agents to synergistically combat the progression of malignant tumors. However, currently common inorganic nanozyme-based drug delivery systems still face challenges such as suboptimal biosafety, inadequate stability, and inferior tumor selectivity. Herein, a super-stable amino acid-based metallo-supramolecular nanoassembly (FPIC NPs) with peroxidase (POD)- and glutathione oxidase (GSHOx)-like activities was fabricated via Pt4+-driven coordination co-assembly of l-cysteine derivatives, the chemotherapeutic drug curcumin (Cur), and the photosensitizer indocyanine green (ICG). The superior POD- and GSHOx-like activities could not only catalyze the decomposition of endogenous hydrogen peroxide into massive hydroxyl radicals, but also deplete the overproduced glutathione (GSH) in cancer cells to weaken intracellular antioxidant defenses. Meanwhile, FPIC NPs would undergo degradation in response to GSH to specifically release Cur, causing efficient mitochondrial damage. In addition, FPIC NPs intrinsically enable fluorescence/photoacoustic imaging to visualize tumor accumulation of encapsulated ICG in real time, thereby determining an appropriate treatment time point for tumoricidal photothermal (PTT)/photodynamic therapy (PDT). In vitro and in vivo findings demonstrated the quadruple orchestration of catalytic therapy, chemotherapeutics, PTT, and PDT offers conspicuous antineoplastic effects with minimal side reactions. This work may provide novel ideas for designing supramolecular nanoassemblies with multiple enzymatic activities and therapeutic functions, allowing for wider applications of nanozymes and nanoassemblies in biomedicine.

ICG-labeled PD-L1-antagonistic affibody dimer for tumor imaging and enhancement of tumor photothermal-immunotherapy

In clinical practice, tumor-targeting diagnosis and immunotherapy against programmed death ligand 1 (PD-L1) have a significant impact. In this research, a PD-L1-antagonistic affibody dimer (ZPD-L1) was successfully prepared through Escherichia coli expression system, and conjugated with the photosensitizer of ICG via N-hydroxysuccinimide (NHS) ester to develop a novel tumor-targeting agent (ICG-ZPD-L1) for both tumor imaging diagnosis and photothermal-immunotherapy simultaneously. In vitro, ZPD-L1 could specifically bind to PD-L1-positive LLC and MC38 tumor cells, and ICG-ZPD-L1-mediated photothermal therapy (PTT) also showed excellent phototoxicity to these tumor cells. In vivo, ICG-ZPD-L1 selectively enriched into the PD-L1-positive MC38 tumor tissues, and the high-contrast optical imaging of tumors was obtained. ICG-ZPD-L1-mediated PTT exhibited a potent anti-tumor effect in vivo due to its remarkable photothermal properties. Furthermore, ICG-ZPD-L1-mediated PTT significantly induced the immunogenic cell death (ICD) of primary tumors, promoted maturation of dendritic cells (DCs), up-regulated anti-tumor immune response, enhanced immunotherapy, and superiorly inhibited the growth of metastatic tumors. In addition, ICG-ZPD-L1 showed favorable biosafety throughout the brief duration of treatment. In summary, these results suggest that ICG-ZPD-L1 is a multifunctional tumor-targeting drug integrating tumor imaging diagnosis and photothermal-immunotherapy, and has great guiding significance for the diagnosis and treatment of clinical PD-L1-positive tumor patients.

Acid-Activated TAT Peptide-Modified Biomimetic Boron Nitride Nanoparticles for Enhanced Targeted Codelivery of Doxorubicin and Indocyanine Green: A Synergistic Cancer Photothermal and Chemotherapeutic Approach

The evolution of nano-drug delivery systems addresses the limitations of conventional cancer treatments with stimulus-responsive nanomaterial-based delivery systems presenting temporal and spatial advantages. Among various nanomaterials, boron nitride nanoparticles (BNNs) demonstrate significant potential in drug delivery and cancer treatment, providing a high drug loading capacity, multifunctionality, and low toxicity. However, the challenge lies in augmenting nanomaterial accumulation exclusively within tumors while preserving healthy tissues. To address this, we introduce a novel approach involving cancer cell membrane-functionalized BNNs (CM-BIDdT) for the codelivery of doxorubicin (Dox) and indocyanine green to treat homologous tumor. The cancer cell membrane biomimetic CM-BIDdT nanoparticles possess highly efficient homologous targeting capabilities toward tumor cells. The surface modification with acylated TAT peptides (dTAT) further enhances the nanoparticle intracellular accumulation. Consequently, CM-BIDdT nanoparticles, responsive to the acidic tumor microenvironment, hydrolyze amide bonds, activate the transmembrane penetrating function, and achieve precise targeting with substantial accumulation at the tumor site. Additionally, the photothermal effect of CM-BIDdT under laser irradiation not only kills cells through thermal ablation but also destroys the membrane on the surface of the nanoparticles, facilitating Dox release. Therefore, the fabricated CM-BIDdT nanoparticles orchestrate chemo-photothermal combination therapy and effectively inhibit tumor growth with minimal adverse effects, holding promise as a new modality for synergistic cancer treatment.

Morusin-Cu(II)-indocyanine green nanoassembly ignites mitochondrial dysfunction for chemo-photothermal tumor therapy

Nanoscale drug delivery systems derived from natural bioactive materials accelerate the innovation and evolution of cancer treatment modalities. Morusin (Mor) is a prenylated flavonoid compound with high cancer chemoprevention activity, however, the poor water solubility, low active pharmaceutical ingredient (API) loading content, and instability compromise its bioavailability and therapeutic effectiveness. Herein, a full-API carrier-free nanoparticle is developed based on the self-assembly of indocyanine green (ICG), copper ions (Cu2+) and Mor, termed as IMCNs, via coordination-driven and π-π stacking for synergistic tumor therapy. The IMCNs exhibits a desirable loading content of Mor (58.7 %) and pH/glutathione (GSH)-responsive motif. Moreover, the photothermal stability and photo-heat conversion efficiency (42.8 %) of IMCNs are improved after coordination with Cu2+ and help to achieve photothermal therapy. Afterward, the released Cu2+ depletes intracellular overexpressed GSH and mediates Fenton-like reactions, and further synergizes with ICG at high temperatures to expand oxidative damage. Furthermore, the released Mor elicits cytoplasmic vacuolation, expedites mitochondrial dysfunction, and exerts chemo-photothermal therapy after being combined with ICG to suppress the migration of residual live tumor cells. In vivo experiments demonstrate that IMCNs under laser irradiation could excellently inhibit tumor growth (89.6 %) through the multi-modal therapeutic performance of self-enhanced chemotherapy/coordinated-drugs/ photothermal therapy (PTT), presenting a great potential for cancer therapy.

Combined Ferritin Nanocarriers with ICG for Effective Phototherapy Against Breast Cancer

Introduction

Photodynamic Therapy (PDT) is a promising, minimally invasive treatment for cancer with high immunostimulatory potential, no reported drug resistance, and reduced side effects. Indocyanine Green (ICG) has been used as a photosensitizer (PS) for PDT, although its poor stability and low tumor-target specificity strongly limit its efficacy. To overcome these limitations, ICG can be formulated as a tumor-targeting nanoparticle (NP).

Methods

We nanoformulated ICG into recombinant heavy-ferritin nanocages (HFn-ICG). HFn has a specific interaction with transferrin receptor 1 (TfR1), which is overexpressed in most tumors, thus increasing HFn tumor tropism. First, we tested the properties of HFn-ICG as a PS upon irradiation with a continuous-wave diode laser. Then, we evaluated PDT efficacy in two breast cancer (BC) cell lines with different TfR1 expression levels. Finally, we measured the levels of intracellular endogenous heavy ferritin (H-Fn) after PDT treatment. In fact, it is known that cells undergoing ROS-induced autophagy, as in PDT, tend to increase their ferritin levels as a defence mechanism. By measuring intracellular H-Fn, we verified whether this interplay between internalized HFn and endogenous H-Fn could be used to maximize HFn uptake and PDT efficacy.

Results

We previously demonstrated that HFn-ICG stabilized ICG molecules and increased their delivery to the target site in vitro and in vivo for fluorescence guided surgery. Here, with the aim of using HFn-ICG for PDT, we showed that HFn-ICG improved treatment efficacy in BC cells, depending on their TfR1 expression. Our data revealed that endogenous H-Fn levels were increased after PDT treatment, suggesting that this defence reaction against oxidative stress could be used to enhance HFn-ICG uptake in cells, increasing treatment efficacy.

Conclusion

The strong PDT efficacy and peculiar Trojan horse-like mechanism, that we revealed for the first time in literature, confirmed the promising application of HFn-ICG in PDT.

A mitochondrion-targeted cyanine agent for NIR-II fluorescence-guided surgery combined with intraoperative photothermal therapy to reduce prostate cancer recurrence

Poorly identified tumor boundaries and nontargeted therapies lead to the high recurrence rates and poor quality of life of prostate cancer patients. Near-infrared-II (NIR-II) fluorescence imaging provides certain advantages, including high resolution and the sensitive detection of tumor boundaries. Herein, a cyanine agent (CY7-4) with significantly greater tumor affinity and blood circulation time than indocyanine green was screened. By binding albumin, the absorbance of CY7-4 in an aqueous solution showed no effects from aggregation, with a peak absorbance at 830 nm and a strong fluorescence emission tail beyond 1000 nm. Due to its extended circulation time (half-life of 2.5 h) and high affinity for tumor cells, this fluorophore was used for primary and metastatic tumor diagnosis and continuous monitoring. Moreover, a high tumor signal-to-noise ratio (up to ~ 10) and excellent preferential mitochondrial accumulation ensured the efficacy of this molecule for photothermal therapy. Therefore, we integrated NIR-II fluorescence-guided surgery and intraoperative photothermal therapy to overcome the shortcomings of a single treatment modality. A significant reduction in recurrence and an improved survival rate were observed, indicating that the concept of intraoperative combination therapy has potential for the precise clinical treatment of prostate cancer.

Accelerating the remodeling of collagen in cutaneous full-thickness wound using FIR soldering technology with bio-targeting nanocomposites hydrogel

A novel composite wound dressing hydrogel by incorporating single-walled carbon nanotubes and indocyanine green into a dual-crosslinked hydrogel through Schiff base reaction was developed. The objective was to prevent wound infection and enhance the thermal effect induced by laser energy. The hydrogel matrix was constructed using oxidized gelatin, pre-crosslinked with calcium ions, along with carboxymethyl chitosan, crosslinked via Schiff base reaction. Optimization of the blank hydrogel's gelation time, swelling index, degradation rate, and mechanical properties was achieved by adding 0.1% SWCNT and 0.1% ICG. Among them, the SWCNT-loaded hydrogel BCG-SWCNT exhibited superior performance overall: a gelation time of 102 s; a swelling index above 30 after equilibrium swelling; a degradation rate of 100.5% on the seventh day; and a compressive modulus of 8.8 KPa. It displayed significant inhibition against methicillin-resistant Staphylococcus aureus infection in wounds. When combined with laser energy usage, the composite hydrogel demonstrated excellent pro-healing activity in rats.

Tea polyphenol-derived nanomedicine for targeted photothermal thrombolysis and inflammation suppression

Thrombotic diseases impose a significant global health burden, and conventional drug-based thrombolytic therapies are encumbered by the risk of bleeding complications. In this study, we introduce a novel drug-free nanomedicine founded on tea polyphenols nanoparticles (TPNs), which exhibits multifaceted capabilities for localized photothermal thrombolysis. TPNs were synthesized through a one-pot process under mild conditions, deriving from the monomeric epigallocatechin-3-gallate (EGCG). Within this process, indocyanine green (ICG) was effectively encapsulated, exploiting multiple intermolecular interactions between EGCG and ICG. While both TPNs and ICG inherently possessed photothermal potential, their synergy significantly enhanced photothermal conversion and stability. Furthermore, the nanomedicine was functionalized with cRGD for targeted delivery to activated platelets within thrombus sites, eliciting robust thrombolysis upon laser irradiation across diverse thrombus types. Importantly, the nanomedicine's potent free radical scavenging abilities concurrently mitigated vascular inflammation, thus diminishing the risk of disease recurrence. In summary, this highly biocompatible multifunctional nanomaterial holds promise as a comprehensive approach that combines thrombolysis with anti-inflammatory actions, offering precision in thrombosis treatment.

Injectable Alginate Complex Hydrogel Loaded with Dual-Drug Nanovectors Offers Effective Photochemotherapy against Triple-Negative Breast Cancer

Triple-negative breast cancer (TNBC), accounting for approximately 20% of breast cancer cases, is a particular subtype that lacks tumor-specific targets and is difficult to treat due to its high aggressiveness and poor prognosis. Chemotherapy remains the major systemic treatment for TNBC. However, its applicability and efficacy in the clinic are usually concerning due to a lack of targeting, adverse side effects, and occurrence of multidrug resistance, suggesting that the development of effective therapeutics is still highly demanded nowadays. In this study, an injectable alginate complex hydrogel loaded with indocyanine green (ICG)-entrapped perfluorocarbon nanoemulsions (IPNEs) and camptothecin (CPT)-doped chitosan nanoparticles (CCNPs), named IPECCNAHG, was developed for photochemotherapy against TNBC. IPNEs with perfluorocarbon can induce hyperthermia and generate more singlet oxygen than an equal dose of free ICG upon near-infrared (NIR) irradiation to achieve photothermal and photodynamic therapy. CCNPs with positive charge may facilitate cellular internalization and provide sustained release of CPT to carry out chemotherapy. Both nanovectors can stabilize agents in the same hydrogel system without interactions. IPECCNAHG integrating IPNEs and CCNPs enables stage-wise combinational therapeutics that may overcome the issues described above. With 60 s of NIR irradiation, IPECCNAHG significantly inhibited the growth of MDA-MB-231 tumors in the mice without systemic toxicity within the 21 day treatment. We speculate that such anticancer efficacy was accomplished by phototherapy followed by chemotherapy, where cancer cells were first destroyed by IPNE-derived hyperthermia and singlet oxygen, followed by sustained damage with CPT after internalization of CCNPs; a two-stage tumoricidal process. Taken together, the developed IPECCNAHG is anticipated to be a feasible tool for TNBC treatment in the clinic.

Choroidal Vascular Changes on Ultrawidefield Indocyanine Green Angiography in Central Serous Chorioretinopathy: CERTAIN Study Report 1

PURPOSE

Choroidal venous overload was recently suggested to be a pathogenetic factor in central serous chorioretinopathy (CSC). Manifestations of venous overload on ultrawidefield indocyanine green angiography (UWF ICGA) include asymmetric arterial choroidal filling (AACF), enlarged choroidal vessels ("pachyvessels"), and asymmetric venous drainage (AVD) leading to choroidal intervortex venous anastomoses (CVAs) accompanied by choroidal vascular hyperpermeability (CVH). The purpose of the current study is to assess the presence of these signs of venous overload in a large cohort of CSC patients.

DESIGN

Monocentric retrospective cohort study.

PARTICIPANTS

Consecutive CSC patients seen at a large tertiary referral center.

METHODS

For the CERTAIN study, patients underwent a standardized imaging protocol including UWF ICGA. Features of choroidal venous overload were graded for each eye individually by 2 independent graders and, in case of disagreement, by a third grader.

MAIN OUTCOME MEASURES

Presence of AAFC, pachyvessels, AVD, CVA, and CVH.

RESULTS

In total, 178 eyes of 91 patients were included in this study. Mean patient age was 47.6 (± 12.0) years and 75 patients (82%) were male. The 116 eyes (65%) that showed subretinal fluid were considered affected (bilateral disease in 29 patients). In affected eyes, AACF was present in 62 eyes (85% of gradable eyes), pachyvessels in 102 eyes (88%), AVD in 81 eyes (74%), CVA in 107 eyes (94%), and CVH in 100% of affected eyes. For fellow eyes, prevalence of pachyvessels (94%), AVD (67%), and CVA (90%) was similar to affected eyes, whereas CVH was present in 85% of fellow eyes. Intergrader agreement was excellent for CVH (94%), and 74%-82% for all other criteria. Patients with pachyvessels and AVD in 1 eye were more likely to also show the same characteristic in the fellow eye (odds ratios 22.2 and 9.9, P < 0.01).

CONCLUSIONS

Signs of venous overload are seen in the vast majority of CSC patients, both in affected and unaffected eyes. Although pachyvessels, AVD, and CVA are observed frequently, CVH was observed in all affected eyes, showed excellent intergrader reliability, and is diagnostic for CSC. This supports the concept of choroidal venous overload as a major factor in CSC pathogenesis.

FINANCIAL DISCLOSURE(S)

Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

Indocyanine Green Angiography

The choroid plays an important role in the pathophysiology of the eye. Multimodal imaging offers different techniques to examine the choroid. Fundus fluorescein angiography offers limited visualization of the deep layers of the fundus due to the barrier property of the retinal pigment epithelium. Therefore, indocyanine green angiography (ICGA) is widely used in the angiographic examination of the choroidal structure. ICGA is an important component of multimodal imaging in the diagnosis and treatment of many degenerative, tumoral, and inflammatory diseases of the choroid and retina. This review presents the general characteristics of ICGA and a practical approach to its clinical use.

Calcium-enriched carbon nanoparticles loaded with indocyanine green for near-infrared fluorescence imaging-guided synergistic calcium overload, photothermal therapy, and glutathione-depletion-enhanced photodynamic therapy

Combining phototherapy with other treatments has significantly advanced cancer therapy. Here, we designed and fabricated calcium-enriched carbon nanoparticles (Ca-CNPs) that could effectively deplete glutathione (GSH) and release calcium ions in tumors, thereby enhancing the efficacy of photodynamic therapy (PDT) and the calcium overload effect that leads to mitochondrial dysfunction. Due to the electrostatic interaction, π-π stacking interaction, multiple hydrogen bonds, and microporous structures, indocyanine green (ICG) was loaded onto the surface of Ca-CNPs with a high loading efficiency of 44.7 wt%. The obtained Ca-CNPs@ICG can effectively improve the photostability of ICG while retaining its ability to generate singlet oxygen (1O2) and undergo photothermal conversion (Ca-CNPs@ICG vs. ICG, 45.1% vs. 39.5%). In vitro and in vivo experiments demonstrated that Ca-CNPs@ICG could be used for near-infrared fluorescence imaging-guided synergistic calcium overload, photothermal therapy, and GSH depletion-enhanced PDT. This study sheds light on the improvement of 1O2 utilization efficiency and calcium overload-induced mitochondrial membrane potential imbalance in tumor cells.

NIR-Triggered Thermosensitive Nanoreactors for Dual-Guard Mechanism-Mediated Precise and Controllable Cancer Chemo-Phototherapy

Thermosensitive nanoparticles can be activated by externally applying heat, either through laser irradiation or magnetic fields, to trigger the release of drug payloads. This controlled release mechanism ensures that drugs are specifically released at the tumor site, maximizing their effectiveness while minimizing systemic toxicity and adverse effects. However, its efficacy is limited by the low concentration of drugs at action sites, which is caused by no specific target to tumor sties. Herein, hyaluronic acid (HA), a gooey, slippery substance with CD44-targeting ability, was conjugated with a thermosensitive polymer poly(acrylamide-co-acrylonitrile) to produce tumor-targeting and thermosensitive polymeric nanocarrier (HA-P) with an upper critical solution temperature (UCST) at 45 °C, which further coloaded chemo-drug doxorubicin (DOX) and photosensitizer Indocyanine green (ICG) to prepare thermosensitive nanoreactors HA-P/DOX&ICG. With photosensitizer ICG acting as the "temperature control element", HA-P/DOX&ICG nanoparticles can respond to temperature changes when receiving near-infrared irradiation and realize subsequent structure depolymerization for burst drug release when the ambient temperature was above 45 °C, achieving programmable and on-demand drug release for effective antitumor therapy. Tumor inhibition rate increased from 61.8 to 95.9% after laser irradiation. Furthermore, the prepared HA-P/DOX&ICG nanoparticles possess imaging properties, with ICG acting as a probe, enabling real-time monitoring of drug distribution and therapeutic response, facilitating precise treatment evaluation. These results provide enlightenment for the design of active tumor targeting and NIR-triggered programmable and on-demand drug release of thermosensitive nanoreactors for tumor therapy.

Multilayer nanodrug delivery system with spatiotemporal drug release improves tumor microenvironment for synergistic anticancer therapy

The inflammatory response is one of the general symptoms that accompany tumorigenesis, the pro-inflammatory factors cyclooxygenase-2 (COX-2) and COX-2-derived prostaglandin-2 (PGE-2) in the inflammatory environment surrounding tumors possess promoting tumor development, metastasis and angiogenesis effects. In addition, the hypoxic environment of tumors severely limits the effectiveness of photodynamic therapy (PDT). In this study, a universal extracellular-intracellular 'on-demand' release nanomedicine DOX@PDA-ICG@MnO2@GN-CEL was developed for the combined fight against malignant tumors using a spatiotemporal controlled gelatin coated polydopamine (PDA@GN) as the carrier and loaded with the chemotherapeutic drug doxorubicin (DOX), the photosensitizer indocyanine green (ICG), the PDT enhancer MnO2and the anti-inflammatory drug celecoxib (CEL) individually. Our results showed that DOX@PDA-ICG@MnO2@GN-CEL could release CEL extracellularly by matrix metalloproteinase-2 response and inhibit the COX-2/PGE-2 pathway, reduce chemotherapy resistance and attenuate the concurrent inflammation. After entering the tumor cells, the remaining DOX@PDA-ICG@MnO2released DOX, ICG and MnO2intracellularly through PDA acid response. MnO2promoted the degradation of endogenous H2O2to generate oxygen under acidic conditions to alleviate the tumor hypoxic environment, enhance PDT triggered by ICG. PDA and ICG exhibited photothermal therapy synergistically, and DOX exerted chemotherapy with reduced chemotherapy resistance. The dual responsive drug release switch enabled the chemotherapeutic, photothermal, photodynamic and anti-inflammatory drugs precisely acted on different sites of tumor tissues and realized a promising multimodal combination therapy.

Influence of photoactivation on tissue response to different dyes used in photodynamic therapy and laser ablation therapy

Laser ablation therapy (LA) uses Indocyanine Green dye (ICG) which efficiently absorbs laser energy and the increased temperature results in an instantaneous flame that chars tissue and microbes. Photodynamic therapy (PDT) uses different dyes that are activated by light to kill bacteria. This study evaluated the biocompatibility of the dye Curcumin (CUR), Methylene Blue (MB), and Indocyanine Green (ICG) before and after laser activation (ACT). Polyethylene tubes containing one of the dyes were implanted in the subcutaneous tissue of 32 rats (4 tubes per rat) which were divided into 8 groups: C - control (saline solution); C + ACT (Red Laser 660 nm); CUR; CUR + ACT (480 nm blue LED); MB; MB + ACT (Red Laser 660 nm); ICG; ICG + ACT (810 nm Infrared Laser). After 7 and 30 days (n = 8/time), the rats were euthanized and the tubes with the surrounding tissue were removed and processed for histological analysis of inflammation using H&E stain, and collagen fiber maturation using picrosirius red (PSR). A two-way analysis of variance statistical test was applied (p < 0.05). At 7 days, regardless of laser activation, the CUR group showed a greater inflammatory infiltrate compared to the ICG and control groups, and the MB group had a greater inflammation only in relation to the control (p < 0.05). At 30 days, CUR and MB groups showed a greater inflammatory infiltrate than the control (p < 0.05). ICG group was equal to the control in both periods, regardless of the laser activation (p > 0.05). Laser activation induced the proliferation of collagen immature fibers at 7 days, regardless of the dye (p < 0.05). The CUR group showed a lower percentage of immature and mature fibers at 7 days, compared to ICG and control (p < 0.05) and, at 30 days, compared to control (p < 0.05). Regardless of laser activation, the ICG showed the results of collagen maturation closest to the control (p > 0.05). It was concluded that all dyes are biocompatible and that laser activation did not interfere with biocompatibility. In addition, the maturity of collagen was adequate before and after the laser activation. These results demonstrate that the clinical use of dyes is safe even when activated with a laser.

Effect of antibacterial photodynamic therapy with chitosan nanoparticles on Aggregatibacter actinomycetemcomitans

BACKGROUND

This study aimed to assess the effect of antibacterial photodynamic therapy (aPDT) with chitosan nanoparticles on Aggregatibacter actinomycetemcomitans (A. actinomycetemcomitans) in the culture medium.

MATERIALS AND METHODS

In this in vitro, experimental study, chitosan nanoparticles (CHNPs) containing indocyanine green (ICG) were first synthesized and characterized. A. actinomycetemcomitans was cultured on trypticase soy agar. The culture media containing A. actinomycetemcomitans were randomly subjected to the following six decontamination protocols: negative control subjected to sterile phosphate buffered saline (PBS) for 5 min, positive control exposed to 0.2 % chlorhexidine (CHX) for 5 min, exposure to 0.25 mg/mL ICG in the dark at 37 °C for 5 min, aPDT with 0.25 mg/mL ICG and diode laser (808 nm, 250 mW, 14.94 J/cm2, 30 s, 1 mm distance, 8 mm tip diameter), exposure to CHNPs containing 0.25 mg/mL ICG in the dark at 37 °C for 5 min, and aPDT with CHNPs containing 0.25 mg/mL ICG and diode laser. The number of colonies was counted, and analyzed by one-way ANOVA and Tamhane test (alpha=0.050).

RESULTS

Antimicrobial PDT with CHNPs, and CHX groups comparably showed the highest decontamination efficacy (P = 0.000).

CONCLUSION

The results showed optimal efficacy of aPDT with CHNPs containing 0.25 mg/mL ICG and 808 nm diode laser for reduction of A. actinomycetemcomitans colony count. Thus, aPDT appears to be as effective as CHX, but with fewer adverse effects.