Oxyhaemoglobin saturation NIR-IIb imaging for assessing cancer metabolism and predicting the response to immunotherapy

Unlocking the Potential of Disulfidptosis: Nanotechnology-Driven Strategies for Advanced Cancer Therapy

Tumor tissues exhibit elevated oxidative stress, with the cystine-glutamate transporter xCT solute carrier family 7 member 11 (xCT/SLC7A11) protecting cancer cells from oxidative damage by facilitating cystine uptake for glutathione synthesis. Disulfidptosis, a newly identified form of programmed cell death (PCD), occurs in cells with high xCT/SLC7A11 expression under glucose-deprived conditions. Distinct from other PCD pathways, disulfidptosis is characterized by aberrant disulfide bond formation and cellular dysfunction, ultimately resulting in cancer cell death. This novel mechanism offers remarkable therapeutic potential by targeting the inherent oxidative stress vulnerabilities of rapidly growing cancer cells. Advances in nanotechnology enable the development of nanomaterials capable of inducing reactive oxygen species (ROS) generation, disrupting disulfide bonds. In addition, they are capable to deliver therapeutic agents directly to tumors, thereby improving therapeutic precision and minimizing off-target effects. Moreover, combining disulfidptosis with ROS-induced immunogenic cell death can remodel the tumor microenvironment and enhance anti-tumor immunity. This review explores the mechanisms underlying disulfidptosis, its therapeutic potential in cancer treatment, and the synergistic role of nanotechnology in amplifying its effects. Selective induction of disulfidptosis using nanomaterials represents a promising strategy for achieving more effective, selective, and less toxic cancer therapies.

A Lifetime Nanosensor for In Vivo pH Quantitative Imaging and Monitoring

Non-invasive, in vivo quantitative imaging for long-term biomarker monitoring is crucial for elucidating disease mechanisms, advancing precision medicine, and transforming diagnostics and therapeutic strategies. However, developing chemical sensors for sustained in vivo quantitative monitoring despite sensor concentration fluctuations, excitation variability, and tissue interference remains a major challenge. Here, a long-lifetime nanosensor based on a lanthanide-dye nanocomposite is presented that overcomes these limitations, enabling precise quantitative in vivo pH monitoring. Benefiting from a 64-fold reversible change in the dye's molar extinction coefficient, this nanosensor enables the dynamic tuning of reversible non-radiative energy transfer (RNET) efficiency (6.42%-35.23%) and luminescence lifetime (265-383 µs). This nanosensor enables 4 h of monitoring of gastrointestinal pH dynamics in mice following proton pump inhibitor (PPI) administration, offering new insights into pharmacodynamic effects across different administration routes and dosages and inter-individual variability in drug efficacy. Moreover, coordination with lanthanide nanocrystals induces a significant shift in the dye's pKa, highlighting the importance of nanomaterial interface engineering. This work establishes a versatile platform for in vivo diagnostics and therapeutic monitoring, marking a significant step forward in precision medicine.

Glutathione: a naturally occurring tripeptide for functional metal nanomaterials

Glutathione (GSH), a naturally occurring tripeptide, plays an important role as an intracellular antioxidant in the physiological microenvironment and participates in redox balance, detoxification, and cellular and disease regulation. The unique structural features of GSH, including the reductive thiol and multiple coordination sites (carboxyl and amino group), make it a significant molecule not only in the physiological context but also as a ligand in the development of functional metal nanomaterials. In this context, GSH's role as a protective ligand and reducing agent in surface etching and ligand exchange reactions has been explored at the molecular level, expanding the diversity of GSH-protected metal nanomaterials. With photoluminescence (PL) as one of its most intriguing properties, investigations into GSH's influence on PL properties emphasize its multifaceted coordination capabilities in surface coating, charge transfer from electron-rich functional groups, chirality arising from its unique structure, and available conjugation sites. Moreover, the biocompatibility of GSH, combined with the synergistic effect of metal components, renders GSH-protected nanomaterials an "Inseparable Duo" highly suited for applications in bio-sensing, bio-imaging via PL radiative decay and anti-cancer bio-therapies through photothermal therapy, photodynamic therapy, and radiotherapy. By exploring the multifaceted roles of GSH, this Perspective aims to highlight pathways including the encouragement of deeper synthetic exploration, innovative design at the bio-nano interface, and expanded nanobiomedical applications.

Programming a multiplex lanthanide nanoparticle for customized cancer treatment with real-time efficiency feedback

Customized cancer therapy relies on timely therapeutic effect evaluation to provide prescription adjustment for individual cases. However, currently reported therapeutic reagents are rarely integrated with imaging probes for self-evaluation of effects. Contrast imaging agents to measure tumor size changes must be administrated separately after therapy, complicating the therapeutic process and delaying reporting time. Herein, we design a customized therapy platform (LNPs-RB/Pep/cRGD) by conjugating lanthanide nanoparticles (LNPs) with the photosensitizer rose bengal, a caspase-3 substrate peptide (with Cy7.5 labelled at the terminal), and the tumor-targeting molecule cRGD. LNPs exhibit NIR-IIb downconversion luminescence under 980 nm/808 nm excitations for in vivo imaging, and visible upconversion luminescence under high-power 980 nm excitation for photodynamic therapy (PDT). By sequentially programming NIR excitation wavelength and power, NIR-IIb-imaging guided PDT and real-time cancer cell apoptosis imaging are achieved as therapeutic efficiency feedback. PDT induces cell apoptosis, generating caspase-3, which cleaves Cy7.5-containing peptide fragments from LNPs. This process corresponds to a recovery in vivo of NIR-IIb ratiometric imaging at 808 nm versus 980 nm excitation. The cleaved Cy7.5-containing peptide fragment is cleared into urine for NIR imaging. Both cell apoptosis imaging processes are completed 12 h after PDT, which is 7 days earlier than tumor size measurement. Therefore, customized therapy is achieved by timely adjusting PDT dosage, enhancing therapeutic efficacy.

Biotin Receptor-Targeting PtIV Oxygen Carrying Prodrug Amphiphile for Alleviating Tumor Hypoxia Induced Immune Chemotherapy Suppression

Platinum (Pt)-based chemotherapeutic agents, known for their potent cytotoxicity, are extensively used in clinical oncology. However, their therapeutic efficacy is severely limited by a variety of factors, particularly the hypoxic tumor microenvironment (TME), which not only impedes effective drug delivery but also triggers immune suppression, further diminishing the antitumor effects of Pt drugs. In response to these challenges, we have developed a biotin receptor (BR)-targeting oxaliplatin (OXA)-based PtIV prodrug, named Lipo-OPtIV-BT, which could encapsulate hemoglobin (Hb) as an oxygen carrier, forming PtIV-loaded lipid nanoparticles (Hb@BTOPtIV). The design of the Hb@BTOPtIV aims to address the dual issues of poor drug delivery and immune suppression by effectively increasing local oxygen tension in the TME. Notably, our findings demonstrate that the cytotoxic effects of the BR-targeting PtIV prodrug and increased oxygen levels synergistically reverse the tumor immune microenvironment, leading to improved antitumor efficacy. We observed that Hb@BTOPtIV significantly improved the biodistribution of the drug, enabling it to preferentially accumulate in tumor regions. Importantly, the enhanced oxygenation within the TME also plays a critical role in reshaping the immune landscape of the tumor, promoting a more favorable immune environment for effective chemotherapy. This reversal of immune suppression is evidenced by increased infiltration of cytotoxic T cells and reduced levels of regulatory T cells (Tregs) within the tumor. These findings highlight the promising potential of using BR-targeting lipid PtIV prodrug amphiphiles to improve drug accumulation at tumor sites and counteract immunosuppression induced by tumor hypoxia.

Xanthene-based NIR organic phototheranostics agents: design strategies and biomedical applications

Fluorescence imaging and phototherapy in the near-infrared window (NIR, 650-1700 nm) have attracted great attention for biomedical applications due to their minimal invasiveness, ultra-low photon scattering and high spatial-temporal precision. Among NIR emitting/absorbing organic dyes, xanthene derivatives with controllable molecular structures and optical properties, excellent fluorescence quantum yields, high molar absorption coefficients and remarkable chemical stability have been extensively studied and explored in the field of biological theranostics. The present study was aimed at providing a comprehensive summary of the progress in the development and design strategies of xanthene derivative fluorophores for advanced biological phototheranostics. This study elucidated several representative controllable strategies, including electronic programming strategies, extension of conjugated backbones, and strategic establishment of activatable fluorophores, which enhance the NIR fluorescence of xanthene backbones. Subsequently, the development of xanthene nanoplatforms based on NIR fluorescence for biological applications was detailed. Overall, this work outlines future efforts and directions for improving NIR xanthene derivatives to meet evolving clinical needs. It is anticipated that this contribution could provide a viable reference for the strategic design of organic NIR fluorophores, thereby enhancing their potential clinical practice in future.

Tailoring the Electrocatalytic Properties of Porphyrin Covalent Organic Frameworks for Highly Selective Oxygen Sensing In Vivo

In vivo selective sensing of oxygen (O2) dynamics in the central nervous system could provide insights into energy metabolism and neural activities. Although the electrocatalytic four-electron oxygen reduction reaction (ORR) paves an effective way to the electrochemical sensing of O2 in vivo, the concurrent hydrogen peroxide reduction reaction (HPRR) within the potential windows for four-electron ORR unfortunately poses a great challenge to the conventional mechanism employed for selective electrochemical O2 sensing. In this work, we find that regulation of the linkers within the skeleton of porphyrin-based covalent organic frameworks (COFs) could improve the selectivity of the O2 sensor against hydrogen peroxide (H2O2). The electrochemical results reveal that the Co porphyrin active sites facilitate the direct four-electron pathway for ORR and that the Co porphyrin-based COF, enriched with pyrene units, shows enhanced four-electron ORR kinetics and better tolerance to HPRR. The theoretical calculation suggests that introducing pyrene units essentially weakens the adsorption of H2O2, leading to suppression of the HPRR. The microsensor fabricated with the Co porphyrin-based COF as the electrocatalyst features a high selectivity for real-time monitoring of O2 in a living rat brain.

Less Is More: Donor Engineering of a Stable Molecular Dye for Bioimaging in the NIR-IIb Window

Fluorescence molecular imaging aims to enhance clarity in the region of interest, particularly in the near-infrared IIb window (NIR-IIb, 1500-1700 nm). To achieve this, we developed a novel small-molecule dye, named DA-5, based on classic cyanine dyes (heptamethine or pentamethine is essential for wavelengths beyond 1000 nm). By reducing excessive polymethine to a single methine and disrupting symmetry to form an asymmetric donor-π-acceptor (D-π-A) architecture, we enhanced the donor's electron-donating capability, yielding emission at 1088 nm. DA-5 exhibits superior properties, including excellent chemo- and photostability, resistance against solvatochromism-caused quenching, and antiaggregation in aqueous solution. With a large Stokes shift (241 nm) and high brightness (321 M-1 cm-1), DA-5 enables high-performance imaging of the lymphatic system, intestinal vessels, whole-body angiography, and cerebral and hindlimb microvasculature in NIR-IIb. This molecular design strategy offers a promising platform for advancing in vivo biophotonics.

An Emerging Toolkit of Ho3+ Sensitized Lanthanide Nanocrystals with NIR-II Excitation and Emission for in Vivo Bioimaging

Optical imaging in the second near-infrared window (NIR-II, 1000-1700 nm) holds great promise for biomedical detection due to reduced tissue scattering and autofluorescence. However, the rational design of NIR-II probes with superior excitation wavelengths to balance the effects of tissue scattering and water absorption remains a great challenge. To address this issue, here we developed a series of Ho3+-sensitized lanthanide (Ln) nanocrystals (NaYF4: Ho, Ln@NaYF4) excited at 1143 nm, featuring tunable emissions ranging from 1000 to 2200 nm for in vivo bioimaging. Precise core-shell engineering (β-NaYF4: Ho@NaYF4: Ln@NaYF4 and β-NaYF4: Ho/Yb@NaYbF4@NaYbF4: Ln@NaYF4) further endows the Ho3+-sensitized system with the capability of energy migration within interfaces, enabling more abundant visible and NIR-II emissions that are unattainable in co-doped structures due to detrimental cross relaxation. Tissue phantom studies demonstrated the superior tissue penetration ability of 1143 photons, especially in imaging experiments through the highly photon-scattering skull, where the fluorescence transmittance of 1143 nm excited nanocrystals was 15% and 10% higher than that of the conventional 808 and 980 excitation, respectively. By leveraging these Ho3+-sensitized nanomaterials with multiemission characteristics and well-selected lanthanide nanomaterials with crosstalk-free excitation, we achieved six-channel NIR-II in vivo imaging, enabling the simultaneous visualization of blood vessels, liver, spleen, stomach, intestine, subcutaneous tumors, and lymph nodes in mice. Our research provides new insights into the design of lanthanide nanocrystals with NIR-II excitation and emission and highlights the potential of these materials in in vivo multichannel detection.

Shedding light on vascular imaging: the revolutionary role of nanotechnology

Vascular dysfunction, characterized by changes in anatomy, hemodynamics, and molecular expressions of vasculatures, is closely linked to the onset and development of diseases, emphasizing the importance of its detection. In clinical practice, medical imaging has been utilized as a significant tool in the assessment of vascular dysfunction, however, traditional imaging techniques still lack sufficient resolution for visualizing the complex microvascular systems. Over the past decade, with the rapid advancement of nanotechnology and the emergence of corresponding detection facilities, engineered nanomaterials offer new alternatives to traditional contrast agents. Compared with conventional small molecule counterparts, nanomaterials possess numerous advantages for vascular imaging, holding the potential to significantly advance related technologies. In this review, the latest developments in nanotechnology-assisted vascular imaging research across different imaging modalities, including contrast-enhanced magnetic resonance (MR) angiography, susceptibility-weighted imaging (SWI), and fluorescence imaging in the second near-infrared window (NIR-II) are summarized. Additionally, the advancements of preclinical and clinical studies related to these nanotechnology-enhanced vascular imaging approaches are outlined, with subsequent discussion on the current challenges and future prospects in both basic research and clinical translation.

Recent advances of versatile fluorophores for multifunctional biomedical imaging in the NIR-II region

Fluorescence imaging in the second near-infrared region (NIR-II, 1000-1700 nm) enables high-resolution visualization of deep-tissue biological architecture and physiopathological events, due to the reduced light absorption, scattering and tissue autofluorescence. Numerous versatile NIR-II fluorescent probes have been reported over the past decades. In this review, we first provide a detailed account of the advantages of fluorescence imaging in the NIR-II region. Following this, the classification, design and performance optimization strategies of NIR-II fluorescent probes are systematically discussed, along with a broad range of biomedical applications in vivo. Finally, the discussion extends to the next generation of fluorescent probes for in vivo imaging and the challenges and perspectives for the clinical translation of fluorescence imaging technology in the NIR-II region.

Facile Alkyne Assembly-Enabled Functional Au Nanosheets for Photoacoustic Imaging-Guided Photothermal/Gene Therapy of Orthotopic Glioblastoma

Treatment of glioblastoma (GBM) remains challenging due to the presence of blood-brain barrier (BBB) and tumor heterogeneity. Herein, Au nanosheets (AuNSs) functionalized with RGD peptides and small interfering RNA (siRNA), referred to as AuNSs-RGD-C≡C-siRNA (ARCR), are prepared to achieve multimodal therapy for GBM. The AuNSs with a large modifiable surface area, intriguing photothermal conversion efficiency (50.26%), and remarkable photothermal stability (44 cycles over 7 h) are created using a well-designed amphiphilic surfactant. Furthermore, alkynyl groups are assembled onto the Au surface within 1 min, enabling strong covalent binding of siRNA to AuNSs and thereby avoiding the interference from biological thiols. Owing to the lipophilicity of the surfactant and the targeting property of RGD, ARCR effectively passes through the BBB and accumulates in GBM tumor regions, allowing near-infrared photoacoustic imaging-guided photothermal/gene therapy. This work proposes a facile strategy to construct theranostic Au-based materials, highlighting the potential of multifunctional nanoagents for GBM therapy.

Advances in Lanthanide-Based NIR-IIb Probes for In Vivo Biomedical Imaging

The past decades have witnessed the significant development and practical interest of in vivo biomedical imaging technologies and optical materials in the second-near infrared (NIR-II, 1000-1700 nm) window. Imaging with the extended emission wavelength toward the long-wavelength end (NIR-IIb, 1500-1700 nm) further offers micrometer imaging resolution and centimeter tissue penetration depth by taking advantage of the much-reduced photon scattering and near-zero tissue autofluorescence background, which have become a very hot research area. This review focuses on the recent advances in the development of lanthanide-based NIR-IIb probes for in vivo biomedical applications. The progress including ratiometric imaging, multiplexed imaging for wide-field and microscopy, lifetime multiplexing and sensing, persistent luminescence, and multimodal imaging is summarized. Challenges and future directions concerning the investigation of the photophysical and photochemical properties of NIR-IIb probes, the selection of near-infrared cameras as well as the potential extension of the NIR-IIb imaging sub-window are pointed out. This review will inspire readers who have a strong interest in developing optical imaging technology and long-wavelength fluorescence probes for high-contrast in vivo biomedical applications.

Radiation-activated PD-L1 aptamer-functionalized nanoradiosensitizer to potentiate antitumor immunity in combined radioimmunotherapy and photothermal therapy

Reactive oxygen species (ROS)-mediated immunogenic cell death (ICD) is crucial in radioimmunotherapy by boosting innate antitumor immunity. However, the hypoxic tumor microenvironment (TME) often impedes ROS production, limiting the efficacy of radiotherapy. To tackle this challenge, a combination therapy involving radiotherapy and immune checkpoint blockade (ICB) with anti-programmed death-ligand 1 (PD-L1) has been explored to enhance antitumor effects and reprogram the immunosuppressive TME. Here, we introduce a novel PD-L1 aptamer-functionalized nanoradiosensitizer designed to augment radiotherapy by increasing X-ray deposition specifically at the tumor site. This innovative X-ray-activated nanoradiosensitizer, comprising gold-MnO2 nanoflowers, efficiently enhances ROS generation under single low-dose radiation and repolarizes M2-like macrophages, thereby boosting antitumor immunity. Additionally, the ICB inhibitor BMS-202 synergizes with the PD-L1 aptamer-assisted nanoradiosensitizer to block the PD-L1 receptor, promoting T cell activation. Furthermore, this nanoradiosensitizer exhibits exceptional photothermal conversion efficiency, amplifying the ICD effect. The PD-L1-targeted nanoradiosensitizer effectively inhibits primary tumor growth and eliminates distant tumors, underscoring the potential of this strategy in optimizing both radioimmunotherapy and photothermal therapy.

Visualization of drug release in a chemo-immunotherapy nanoplatform via ratiometric 19F magnetic resonance imaging

Visualization of drug release in vivo is crucial for improving therapeutic efficacy and preventing inappropriate medication dosing, yet, challenging. Herein, we report a pH-activated chemo-immunotherapy nanoplatform with visualization of drug release in vivo by ratiometric 19F magnetic resonance imaging (19F MRI). This nanoplatform consists of ultra-small histamine-modified perfluoro-15-crown-5-ether (PFCE) nanodroplets loaded with doxorubicin (Dox), which are packaged in trifluoromethyl-containing metal-organic assemblies via coordination-driven self-assembly. The chemical shifts of two types of 19F atoms in the nanoplatform are significantly different in 19F nuclear magnetic resonance (NMR) spectra, which facilitates the implementation of ratiometric 19F MRI without any signal crosstalk. In an acidic tumor microenvironment, this nanoplatform gradually degrades, which results in a sustained drug release with a real-time change in the ratiometric 19F MRI signal. Therefore, a linear correlation between the Dox release profile and ratiometric 19F MRI signal is established to visualize Dox release. Moreover, the pH-triggered disassembly of the nanoplatform leads to cell pyroptosis, which evokes immunogenic cell death (ICD), resulting in the regression of the primary tumor and inhibition of distal tumor growth. This study provides the proof-of-concept application of ratiometric 19F MRI to visualize drug release in vivo.

Neutral Cyanine: Ultra-Stable NIR-II Merocyanines for Highly Efficient Bioimaging and Tumor-Targeted Phototheranostics

Fluorescence imaging (FLI)-guided phototheranostics using emission from the second near-infrared (NIR-II) window show significant potential for cancer diagnosis and treatment. Clinical imaging-used polymethine ionic indocyanine green (ICG) dye is widely adopted for NIR fluorescence imaging-guided photothermal therapy (PTT) research due to its exceptional photophysical properties. However, ICG has limitations such as poor photostability, low photothermal conversion efficiency (PCE), short-wavelength emission peak, and liver-targeting issues, which restrict its wider use. In this study, two ionic ICG derivatives are transformed into neutral merocyanines (mCy) to achieve much-enhanced performance for NIR-II cancer phototheranostics. Initial designs of two ionic dyes show similar drawbacks as ICG in terms of poor photostability and low photothermal performance. One of the modified neutral molecules, mCy890, shows significantly improved stability, an emission peak over 1000 nm, and a high photothermal PCE of 51%, all considerably outperform ICG. In vivo studies demonstrate that nanoparticles of the mCy890 can effectively accumulate at the tumor sites for cancer photothermal therapy guided by NIR-II fluorescence imaging. This research provides valuable insights into the development of neutral merocyanines for enhanced cancer phototheranostics.

Aqueous Grown Quantum Dots with Robust Near-Infrared Fluorescence for Integrated Traumatic Brain Injury Diagnosis and Surgical Monitoring

Surgical intervention is the most common first-line treatment for severe traumatic brain injuries (TBIs) associated with high intracranial pressure, while the complexity of these surgical procedures often results in complications. Surgeons often struggle to comprehensively evaluate the TBI status, making it difficult to select the optimal intervention strategy. Here, we introduce a fluorescence imaging-based technology that uses high-quality silver indium selenide-based quantum dots (QDs) for integrated TBI diagnosis and surgical guidance. These engineered, poly(ethylene glycol)-capped QDs emit in the near-infrared region, are resistant to phagocytosis, and importantly, are ultrastable after the epitaxial growth of an aluminum-doped zinc sulfide shell in the aqueous phase that renders the QDs resistant to long-term light irradiation and complex physiological environments. We found that intravenous injection of QDs enabled both the precise diagnosis of TBI in a mouse model and, more importantly, the comprehensive evaluation of the TBI status before, during, and after an operation to distinguish intracranial from superficial hemorrhages, provide real-time monitoring of the secondary hemorrhage, and guide the decision making on the evacuation of intracranial hematomas. This QD-based diagnostic and monitoring system could ultimately complement existing clinical tools for treating TBI, which may help surgeons improve patient outcomes and avoid unnecessary procedures.

White-light activatable organic NIR-II luminescence nanomaterials for imaging-guided surgery

While second near-infrared (NIR-II) fluorescence imaging is a promising tool for real-time surveillance of surgical operations, the previously reported organic NIR-II luminescent materials for in vivo imaging are predominantly activated by expensive lasers or X-ray with high power and poor illumination homogeneity, which significantly limits their clinical applications. Here we report a white-light activatable NIR-II organic imaging agent by taking advantages of the strong intramolecular/intermolecular D-A interactions of conjugated Y6CT molecules in nanoparticles (Y6CT-NPs), with the brightness of as high as 13315.1, which is over two times that of the brightest laser-activated NIR-II organic contrast agents reported thus far. Upon white-light activation, Y6CT-NPs can achieve not only in vivo imaging of hepatic ischemia reperfusion, but also real-time monitoring of kidney transplantation surgery. During the surgery, identification of the renal vasculature, post-reconstruction assessment of renal allograft vascular integrity, and blood supply analysis of the ureter can be vividly depicted by using Y6CT-NPs with high signal-to-noise ratios upon clinical laparoscopic LED white-light activation. Our work provides efficient molecular design guidelines towards white-light activatable imaging agent and highlights an opportunity for precision imaging theranostics.

Targeting macrophages with multifunctional nanoparticles to detect and prevent atherosclerotic cardiovascular disease

Despite the emergence of novel diagnostic, pharmacological, interventional, and prevention strategies, atherosclerotic cardiovascular disease remains a significant cause of morbidity and mortality. Nanoparticle (NP)-based platforms encompass diverse imaging, delivery, and pharmacological properties that provide novel opportunities for refining diagnostic and therapeutic interventions for atherosclerosis at the cellular and molecular levels. Macrophages play a critical role in atherosclerosis and therefore represent an important disease-related diagnostic and therapeutic target, especially given their inherent ability for passive and active NP uptake. In this review, we discuss an array of inorganic, carbon-based, and lipid-based NPs that provide magnetic, radiographic, and fluorescent imaging capabilities for a range of highly promising research and clinical applications in atherosclerosis. We discuss the design of NPs that target a range of macrophage-related functions such as lipoprotein oxidation, cholesterol efflux, vascular inflammation, and defective efferocytosis. We also provide examples of NP systems that were developed for other pathologies such as cancer and highlight their potential for repurposing in cardiovascular disease. Finally, we discuss the current state of play and the future of theranostic NPs. Whilst this is not without its challenges, the array of multifunctional capabilities that are possible in NP design ensures they will be part of the next frontier of exciting new therapies that simultaneously improve the accuracy of plaque diagnosis and more effectively reduce atherosclerosis with limited side effects.

Biomimetic Tertiary Lymphoid Structures with Microporous Annealed Particle Scaffolds for Cancer Postoperative Therapy

Immunotherapy plays a vital role in cancer postoperative treatment. Strategies to increase the variety of immune cells and their sustainable supply are essential to improve the therapeutic effect of immune cell-based immunotherapy. Here, inspired by tertiary lymphoid structures (TLSs), we present a microfluidic-assisted microporous annealed particle (MAP) scaffold for the persistent recruitment of diverse immune cells for cancer postoperative therapy. Based on the thermochemical responsivity of gelatin methacryloyl (GelMA), the MAP scaffold was fabricated by physical cross-linking and sequential photo-cross-linking of GelMA droplets, which were prepared by microfluidic electrospraying. Due to the encapsulation of liquid nitrogen-inactivated tumor cells and immunostimulant, the generated MAP scaffold could recruit a large number of immune cells, involving T cells, macrophages, dendritic cells, B cells, and natural killer cells, thereby forming the biomimetic TLSs in vivo. In addition, by combination of immune checkpoint inhibitors, a synergistic anticancer immune response was provoked to inhibit tumor recurrence and metastasis. These properties make the proposed MAP scaffold-based artificial TLSs of great value for efficient cancer postoperative therapy.