Characteristics and Differences in Mpox Patients with and without HIV Infection: A Retrospective Cross-Sectional Study in Chengdu, China.

Purpose: To date, there are few reports about mpox case series in China, and scarce information is available about the in-vivo kinetics of T-cell responses in the early stage of mpox infection. This study aims to investigate the clinical difference among mpox patients with and without human immunodeficiency virus (HIV) infection. Patients and Methods: A total of 56 patients diagnosed with mpox by Chengdu Center for Disease Control and Prevention (CDC) and hospitalized in Public Health Clinical Center of Chengdu were retrospectively included and divided into an HIV-infected group (n=23) and a non-HIV-infected group (n=33). Clinical characteristics and serum chemistry findings of mpox patients were collected in order to analyze the differences between the HIV-infected group and the non-HIV-infected group. Results: Multiple laboratory abnormalities, including elevated C-reactive protein (69.1%), hypocalcemia (50.9%), elevated CD3+CD8+T counts (47.0%) and inverted ratio of CD3+CD4+T to CD3+CD8+T (64.7%) were common in mpox cases. There were statistically significant differences (all P < 0.05) in age, serum calcium levels, CD3+CD4+T counts, the ratio of CD3+CD4+T to CD3+CD8+T, proportion with >10 rashes, incidence of proctitis anus and time from rash growth to rash scab shedding between HIV-infected group and non-HIV-infected group. In the early stage of mpox infection, the median of CD3+CD8+T counts in the non-HIV-infected group was significantly higher than that in healthy donors (P<0.001), and the median of CD3+CD4+T/CD3+CD8+T ratio was significantly lower (P<0.001). The median of CD3+CD4+T counts in mpox patients co-infected with HIV significantly decreased compared to the pre-infection level (p =0.033). Conclusion: Our study indicates that mpox co-infected with HIV patients have longer lasting rash lesions and a higher incidence of proctitis anus. T-cell responses may be different between HIV-infected and non-HIV-infected individuals in the early stage of mpox infection.

AIEgens Cross-linked Iron Oxide Nanoparticles Synchronously Amplify Bimodal Imaging Signals in Situ by Tumor Acidity-Mediated Click Reaction.

Activatable dual-modal molecular imaging probes present a promising tool for the diagnosis of malignant tumors. However, synchronously enhancing dual-modal imaging signals under a single stimulus is challenging. Herein, we propose an activatable bimodal probe that integrates aggregation-induced emission luminogens (AIEgens) and iron oxide nanoparticles (IOs) to synergistically enhance near-infrared fluorescence (NIRF) intensity and magnetic resonance (MR) contrast through a tumor acidity-mediated click reaction. Tumor acidity-responsive IOs containing dibenzocyclooctyne groups (termed cDIOs) and AIEgens containing azide groups (termed AATs) can be covalently cross-linked in response to tumor acidity, which leads to a simultaneous enhancement in NIRF intensity (≈12.4-fold) and r2 relaxivity (≈2.8-fold). cDIOs and AATs were effectively activated in mice orthotropic breast tumor, and the cross-linking prolonged their retention in tumor, further augmenting the bimodal signals and expanding imaging time frame. This facile strategy leverages the inherent properties of probes themselves and demonstrates promise in future translational studies.

Self-immolative polyprodrug-based tumor-specific cascade amplificated drug release nanosystem for orchestrated synergistic cancer therapy.

Reactive oxygen species (ROS)-activated prodrugs can potentially improve the selectivity of chemotherapeutics. However, the inability to release sufficient drugs at tumor sites due to the paucity of ROS, which is required for prodrug activation usually limits the antitumor potency. Herein, a delivery nanosystem with self-amplifiable drug release pattern is constructed by encapsulating a tumor specificity ROS inducer NAD(P)H: quinone oxidoreductase-1 (NQO1)-responsive hemicyanine fluorescent dye (NCyNH2) in a ROS-responsive self-immolative polyprodrug nanoparticle for orchestrated oxidation-chemotherapy. In response to ROS stimulation, the self-immolative polyprodrug can degrade and release doxorubicin (DOX) through a domino-like fragmentation, which can impart advanced attributes of this nanosystem such as minimum cleavage events required and maximum cleavage speed for disintegration. Thus, the NCyNH2-loaded self-immolative polyprodrug nanoparticle (SIPN) could be dissociated in response to endogenous ROS, triggering the release of DOX and NCyNH2. Subsequently, the NCyNH2 could be activated by intratumoral overexpressed NQO1 to generate additional ROS, which further induces the amplifiable degradation of self-immolative polyprodrug to release sufficient drugs. The in vitro and in vivo studies consistently demonstrate that SIPN amplifies the drug release efficiency of ROS-responsive polyprodrug by specifically upregulating intratumoral ROS levels, resulting in significant antitumor efficacy with minimal side effects.

Cinnamaldehyde-based poly(thioacetal): A ROS-awakened self-amplifying degradable polymer for enhanced cancer immunotherapy.

Although stimuli-responsive polymers have emerged as promising strategies for intelligent cancer therapy, limited polymer degradation and insufficient drug release remain a challenge. Here, we report a novel reactive oxygen species (ROS)-awakened self-amplifying degradable cinnamaldehyde (CA)-based poly(thioacetal) polymer. The polymer consists of ROS responsive thioacetal (TA) group and CA as the ROS generation agent. The self-amplified polymer degradation process is triggered by endogenous ROS-induced cleavage of the TA group to release CA. The CA released then promotes the generation of more ROS through mitochondrial dysfunction, resulting in amplified polymer degradation. More importantly, poly(thioacetal) itself can trigger immunogenic cell death (ICD) of the tumor cells and its side chains can be conjugated with indoleamine 2,3-dioxygenase 1 (IDO-1) inhibitor to reverse the immunosuppressive tumor microenvironment for synergistic cancer immunotherapy. The self-amplified degradable poly(thioacetal) developed in this work provides insights into the development of novel stimulus-responsive polymers for enhanced cancer immunotherapy.

Bioorthogonal Equipping CAR-T Cells with Hyaluronidase and Checkpoint Blocking Antibody for Enhanced Solid Tumor Immunotherapy.

Adoptive cellular therapy utilizing chimeric antigen receptor redirected T (CAR-T) cells has shown impressive therapeutic effects on hematological malignancies. In contrast, the efficacy of CAR-T therapies in treating solid tumors is still poor, which is largely due to inefficient penetration into solid tumors and the immunosuppressive tumor microenvironment. Herein, we engineered hyaluronidase (HAase) and the checkpoint blocking antibody α-PDL1 on the CAR-T cell surface via highly efficient and biocompatible bioorthogonal click chemistry to improve their therapeutic effects on solid tumors. The modified HAase degrades hyaluronic acid and destroys the tumor extracellular matrix, allowing CAR-T cells to penetrate deeply into solid tumors, as evidenced by in vitro infiltration experiments and in vivo biodistribution studies. In addition, in vitro cytotoxicity studies showed stronger antitumor activity of α-PDL1-decorated cells than traditional CAR-T cells. Importantly, HAase- and α-PDL1-engineered CAR-T cells showed better therapeutic efficacy on two solid tumor models and did not cause significant systemic side effects. In this work, we provide a simple, efficient, and biologically safe chemical strategy to engineer traditional CAR-T cells for enhanced therapeutic efficacy on solid tumors, which can be extended to other adoptive cellular immunotherapies and holds great potential for clinical application.

Time-programmed activation of dual polyprodrugs for synergistic cascade oxidation-chemotherapy.

Combination therapy using multiple drugs with time-programmed administration is promising for enhanced cancer treatment. However, it is still challenging to achieve time-programmed drug release from a single nanocarrier. Here, dual polyprodrugs of hemicyanine dye (CyNH2) and doxorubicin (DOX) are developed to achieve time-programmed prodrug activation for synergistic cascade oxidation therapy and chemotherapy. The polyprodrug NPDOX/Cy, composed of CyNH2, is modified with a glutathione (GSH)-responsive disulfate group, while DOX is modified with a reactive oxygen species (ROS)-response thioketal (TK) group. Upon uptake by cancer cells overexpressing GSH, CyNH2 can be activated quickly and accumulate in the mitochondria to induce mitochondrial damage and ROS upregulation, thus achieving subsequent burst activation of DOX through the ROS-triggered cleavage of the TK linker. The early activation of CyNH2 makes the cancer cells more sensitive to subsequent DOX treatment for a synergistic effect of from oxidation therapy and chemotherapy. Therefore, the polyprodrug with time-programmed drug activation developed in this work provides a promising strategy for synergistic cancer therapy.

Bioorthogonal Pretargeting Strategy for Anchoring Activatable Photosensitizers on Plasma Membranes for Effective Photodynamic Therapy.

Developing novel activatable photosensitizers with excellent plasma membrane targeting ability is urgently needed for smart photodynamic therapy (PDT). Herein, a tumor acidity-activatable photosensitizer combined with a two-step bioorthogonal pretargeting strategy to anchor photosensitizers on the plasma membrane for effective PDT is developed. Briefly, artificial receptors are first anchored on the cell plasma membrane using cell-labeling agents (Az-NPs) via the enhanced permeability and retention effect to achieve the tumor cell labeling. Then, pH-sensitive nanoparticles (S-NPs) modified with dibenzocyclooctyne (DBCO) and chlorin e6 (Ce6) accumulate in tumor tissue and disassemble upon protonation of their tertiary amines in response to the acidic tumor environment, exposing the contained DBCO and Ce6. The selective, highly specific click reactions between DBCO and azide groups enable Ce6 to be anchored on the tumor cell surface. Upon laser irradiation, the cell membrane is severely damaged by the cytotoxic reactive oxygen species, resulting in remarkable cellular apoptosis. Taken together, the membrane-localized PDT by our bioorthogonal pretargeting strategy to anchor activatable photosensitizers on the plasma membrane provides a simple but effective method for enhancing the therapeutic efficacy of photosensitizers in anticancer therapy.

Dual-Drug Backboned Polyprodrug with a Predefined Drug Combination for Synergistic Chemotherapy.

The codelivery of drugs at specific optimal ratios to cancer cells is vital for combination chemotherapy. However, most of the current strategies are unable to coordinate the loading and release of drug combinations to acquire precise and controllable synergistic ratios. In this work, we designed an innovative dual-drug backboned and reduction-sensitive polyprodrug PEG-P(MTO-ss-CUR) containing the anticancer drugs mitoxantrone (MTO) and curcumin (CUR) at an optimal synergistic ratio to reverse drug resistance. Due to synchronous drug activation and polymer backbone degradation, drug release at the predefined ratio with a synergistic anticancer effect was demonstrated by in vitro and in vivo experiments. Therefore, the dual-drug delivery system developed in this work provides a novel and efficient strategy for combination chemotherapy.

Polyprodrug with glutathione depletion and cascade drug activation for multi-drug resistance reversal.

High intracellular glutathione (GSH) levels play an important role in multidrug resistance (MDR) in cancer cells. It remains challenging to develop a drug delivery system that is simultaneously capable of GSH depletion and drug activation for multidrug resistance reversal. Herein, we designed a polyprodrug (denoted as PSSD) based on poly(disulfide) conjugated with doxorubicin (DOX) on the polymer side chains that exhibits GSH depletion and cascade DOX activation for drug resistance reversal. The poly(disulfide) backbone with a high disulfide density depletes intracellular antioxidant GSH via the disulfide-thiol exchange reaction to disrupt intracellular redox homeostasis in cells. Simultaneously, DOX can be activated through a cascade reaction, and degradation of the poly(disulfide) backbone further facilitates its drug release. Therefore, poly(disulfide) can be used as a GSH scavenger to reverse MDR as well as a prodrug backbone to target high intracellular GSH levels in cancer cells, providing a general strategy for drug resistance reversal.

Intercellular delivery of bioorthogonal chemical receptors for enhanced tumor targeting and penetration.

Targeted drug delivery using biological ligands can improve the precision of cancer therapy. However, this active targeting strategy is limited in tumor targeting and penetration abilities due to the paucity and heterogeneous distribution of targeted receptors in tumor cells, thus compromising the treatment outcomes. In this study, we developed an alternative active targeting strategy for enhanced tumor targeting and penetration through synthetic nanoparticle-mediated metabolic tumor ligand labeling for intercellular delivery of bioorthogonal chemical receptors combined with in vivo bioorthogonal click chemistry. Briefly, artificial azide-containing ligands were first labeled on perivascular tumor cells by nanoscale metabolic precursors (Az-NPs) via the enhanced permeability and retention (EPR) effect and metabolic engineering of the tumor cells. Through transport by extracellular vesicles (EVs) secreted by perivascular tumor cells, the azide-containing ligands can be autonomously transported intercellularly to adjacent cells and further spread throughout tumor tissues and label bioorthogonal ligands on cells that are not in proximity to blood vessels. Then, water-soluble dibenzocyclooctyne-modified chlorin e6 (DBCO-Ce6) was intravenously injected to react selectively, efficiently and irreversibly with the azide groups on the cell surface through an in vivo bioorthogonal click reaction. Enhanced tumor accumulation and penetration of DBCO-Ce6 was achieved through this strategy, resulting in improved therapeutic efficiency with laser irradiation for photodynamic therapy. Therefore, the artificial azide-containing ligand targeting strategy by nanoparticle-mediated metabolic labeling through the EPR effect combined with bioorthogonal click chemistry may provide an alternative strategy for enhanced tumor targeting and penetration with broad applications.

A General Strategy for Macrotheranostic Prodrug Activation: Synergy between the Acidic Tumor Microenvironment and Bioorthogonal Chemistry.

Prodrugs activated by endogenous stimuli face the problem of tumor heterogeneity. Bioorthogonal prodrug activation that utilizes an exogenous click reaction has the potential to solve this problem, but most of the strategies currently used rely on the presence of endogenous receptors or overexpressed enzymes. We herein integrate the acidic, extracellular microenvironment of a tumor and a click reaction as a general strategy for prodrug activation. This was achieved by using a tumor pH-responsive polymer containing tetrazine groups, which formed unreactive micelles in the blood but disassembled in response to tumor pH. The vinyl ether group on the macrotheranostic prodrug (CyPVE) is activated by the tetrazine groups, which was confirmed by tumor-specific fluorescence activation and phototoxicity restoration. Therefore, the bioorthogonal reactions in the context of the ubiquitous acidic tumor microenvironment can provide a general strategy for bioorthogonal prodrug activation.

Size-Switchable Nanoparticles with Self-Destructive and Tumor Penetration Characteristics for Site-Specific Phototherapy of Cancer.

The normoxic and hypoxic microenvironments in solid tumors cause cancer cells to show different sensitivities to various treatments. Therefore, it is essential to develop different therapeutic modalities based on the tumor microenvironment. In this study, we designed size-switchable nanoparticles with self-destruction and tumor penetration characteristics for site-specific phototherapy of cancer. This was achieved by photodynamic therapy in the perivascular normoxic microenvironment due to high local oxygen concentrations and photothermal therapy (PTT) in the hypoxic microenvironment, which are not in proximity to blood vessels due to a lack of effective approaches for heat transfer. In brief, a poly(amidoamine) dendrimer with photothermal agent indocyanine green (PAMAM-ICG) was conjugated to the amphiphilic polymer through a singlet oxygen-responsive thioketal linker and then loaded with photosensitizer chlorin e6 (Ce6) to construct a nanotherapy platform (denoted as SNPICG/Ce6). After intravenous injection, SNPICG/Ce6 was accumulated at the perivascular sites of the tumor. The singlet oxygen produced by Ce6 can ablate the tumor cells in the normoxic microenvironment and simultaneously cleave the thioketal linker, allowing the release of small PAMAM-ICGs with improved tumor penetration for PTT in the hypoxic microenvironment. This tailored site-specific phototherapy in normoxic and hypoxic microenvironments provides an effective strategy for cancer therapy.