Engineered Microrobots for Targeted Delivery of Bacterial Outer Membrane Vesicles (OMV) in Thrombus Therapy.

In the realm of thrombosis treatment, bioengineered outer membrane vesicles (OMVs) offer a novel and promising approach, as they have rich content of bacterial-derived components. This study centers on OMVs derived from Escherichia coli BL21 cells, innovatively engineered to encapsulate the staphylokinase-hirudin fusion protein (SFH). SFH synergizes the properties of staphylokinase (SAK) and hirudin (HV) to enhance thrombolytic efficiency while reducing the risks associated with re-embolization and bleeding. Building on this foundation, this study introduces two cutting-edge microrobotic platforms: SFH-OMV@H for venous thromboembolism (VTE) treatment, and SFH-OMV@MΦ, designed specifically for cerebral venous sinus thrombosis (CVST) therapy. These platforms have demonstrated significant efficacy in dissolving thrombi, with SFH-OMV@H showcasing precise vascular navigation and SFH-OMV@MΦ effectively targeting cerebral thrombi. The study shows that the integration of these bioengineered OMVs and microrobotic systems marks a significant advancement in thrombosis treatment, underlining their potential to revolutionize personalized medical approaches to complex health conditions.

Magnetically Powered Immunogenic Macrophage Microrobots for Targeted Multimodal Cancer Therapy.

Motile microrobots open a new realm for disease treatment. However, the concerns of possible immune elimination, targeted capability and limited therapeutic avenue of microrobots constrain its practical biomedical applications. Herein, a biogenic macrophage-based microrobot loaded with magnetic nanoparticles and bioengineered bacterial outer membrane vesicles (OMVs), capable of magnetic propulsion, tumor targeting, and multimodal cancer therapy is reported. Such cell robots preserve intrinsic properties of macrophages for tumor suppression and targeting, and bioengineered OMVs for antitumor immune regulation and fused anticancer peptides. Cell robots display efficient magnetic propulsion and directional migration in the confined space. In vivo tests show that cell robots can accumulate at the tumor site upon magnetic manipulation, coupling with tumor tropism of macrophages to greatly improve the efficacy of its multimodal therapy, including tumor inhibition of macrophages, immune stimulation, and antitumor peptides of OMVs. This technology offers an attractive avenue to design intelligent medical microrobots with remote manipulation and multifunctional therapy capabilities for practical precision treatment.

Ovarian Granulosa Cell Tumor Initially Presenting as a Giant Liver Mass Radiologically Mimicking Primary Cystic Cholangiocarcinoma.

BACKGROUND: Ovarian granulosa cell tumor (GCT) is a rare type of malignant sex-cord stromal tumor, with adult and juvenile types. The ovarian GCT initially presented as a giant liver mass clinically mimicking primary cholangiocarcinoma is exceedingly rare. CASE REPORT: We report such a case of a 66-year-old woman who presented with right upper quadrant pain. Abdominal magnetic resonance imaging (MRI) and a subsequently fused positron emission tomography/computed tomography (PET/CT) showed a solid and cystic mass with hypermetabolic activity concerning intrahepatic primary cystic cholangiocarcinoma. A fine-needle core biopsy of the liver mass showed coffee-bean-shaped tumor cells. The tumor cells were positive for Forkhead Box L2 (FOXL2), inhibin, Wilms tumor protein 1 (WT-1), steroidogenic factor 1 (SF1), vimentin, estrogen receptor (ER), and smooth muscle actin (SMA). The histologic features and immunoprofile supported a metastatic sex-cord stromal tumor favoring granulosa cell tumor, adult type. Strata next-generation sequencing test was performed on the liver biopsy and FOXL2 c.402C>G (p.C134W) mutation was present, consistent with granulosa cell tumor. CONCLUSION: To the best of our knowledge, this is the first documented case of ovarian granulosa cell tumor with FOXL2 mutation initially presenting as a giant liver mass clinically mimicking primary cystic cholangiocarcinoma.

Bioengineered bacterial outer membrane vesicles encapsulated Polybia-mastoparan I fusion peptide as a promising nanoplatform for bladder cancer immune-modulatory chemotherapy.

Background: Nanosized bacterial outer membrane vesicles (OMVs) secreted by Gram-negative bacteria have emerged as a novel antitumor nanomedicine reagent due to their immunostimulatory properties. The encapsulated bacterial composition in OMVs can be edited via manipulating bioengineering technology on paternal bacteria, allowing us to design an ingenious antitumor platform by loading the Polybia-mastoparan I (MPI) fusion peptide into OMVs. Methods: OMVs containing the MPI fusion peptide were obtained from bioengineered Escherichia coli transformed with recombinant plasmid. The antitumor efficacy of bioengineered OMVs in vitro was verified by performing cell viability and wound-healing and apoptosis assays using MB49 and UMUC3 cells, respectively. Subcutaneous MB49 tumor-bearing mice were involved to investigate the tumor inhibition ability of bioengineered OMVs. Moreover, the activated immune response in tumor and the biosafety were also evaluated in detail. Results: The resulting OMVs had the successful encapsulation of MPI fusion peptides and were subjected to physical characterization for morphology, size, and zeta potential. Cell viabilities of bladder cancer cells including MB49 and UMUC3 rather than a non-carcinomatous cell line (bEnd.3) were decreased when incubated with bioengineered OMVs. In addition, bioengineered OMVs restrained migration and induced apoptosis of bladder cancer cells. With intratumor injection of bioengineered OMVs, growths of subcutaneous MB49 tumors were significantly restricted. The inherent immunostimulation of OMVs was demonstrated to trigger maturation of dendritic cells (DCs), recruitment of macrophages, and infiltration of cytotoxic T lymphocytes (CTLs), resulting in the increased secretion of pro-inflammatory cytokines (IL-6, TNF-α, and IFN-γ). Meanwhile, several lines of evidence also indicated that bioengineered OMVs had satisfactory biosafety. Conclusion: Bioengineered OMVs fabricated in the present study were characterized by strong bladder cancer suppression and great biocompatibility, providing a new avenue for clinical bladder cancer therapy.

Pulmonary delivery of size-transformable nanoparticles improves tumor accumulation and penetration for chemo-sonodynamic combination therapy.

Very little is currently known about how inhaled nanomedicine for lung cancer treatment overcomes biological barriers hampering the tumor availability of drug and nanoparticles. Here, we developed a size-transformable nanocarrier (~ 119 nm) in which small-size nanoparticles (~ 28 nm) were loaded in the large nanocarrier after the addition of modified hyaluronan and could be released upon size-transformation at tumor tissue. Subsequently, the pulmonary and tumor pharmacokinetics of the two nanocarriers containing 7-ethyl-10-hydroxycamptothecin (SN38) and a covalently linked fluorescent sonosensitizer were comparatively investigated after intratracheal instillation to mice bearing orthotopic Lewis lung carcinoma tumors. The results showed that both instilled nanoparticles seemed to transport drug to tumor by direct access and transcytosis of nanoparticles, and diffusion of the released drug with the latter accounting for a great proportion of the drug tumor bioavailability. Relative to the small-size nanocarrier, the size-transformable counterpart appeared to restrict the mucociliary and absorption clearances from the lung and the clearance from the tumor interstitium to circulation, leading to increases in lung and tumor bioavailability of SN38 by 58.5% and 199%, respectively. In addition, the size-transformable nanoformulation conferred deep tumor penetration and sustained levels of both sonosensitizer and SN38 within tumors and simultaneously exerted sonodynamic- and chemo-therapies. Overall, the pulmonary delivery of size-transformable nanocarrier could co-deliver sonosensitizer and drug to deep tumor sites with enhanced tumor accumulation to realize combination therapy in lung cancer.

Pollen Typhae-Based Magnetic-Powered Microrobots toward Acute Gastric Bleeding Treatment.

Traditional Chinese herbal medicine (TCHM) is the naturally available pharmaceutical with millennia of evolution from ancient China, capable of a superior therapeutic index and minimized unwanted effects on the human body. This work presents a therapeutic microrobotic platform based on pollen typhae (PT), a typical type of TCHM, fabricated by coating porous PT microspheres with Fe3O4 nanoparticles (PT robots) via electrostatic adsorption. The PT robots exhibit effective and controllable motion in various biological media upon external magnetic control and, meanwhile, preserve the inherent hemostasis property of PT. The blood clotting capacity of PT robots is attributed to their stimulation of the endogenous blood coagulation pathway and platelets with increased counts, which could be further improved by their effective magnetic propulsion. The remote magnetic control also allows the manipulation of PT robots in mice stomach, inducing enhanced binding and prolonged retention of PT robots in stomach mucosa. Moreover, PT robots upon magnetic control show an enhanced hemostatic effect in treating the mice bearing acute gastric bleeding compared with other passive groups. This work offers a facile and feasible route to integrate TCHM with manmade micromachines possessing the innate curative features of TCHM. Such a design expanded the versatility of microrobots and can be generalized to vast types of TCHM for broader biomedical applications.

Magnetic-Powered Janus Cell Robots Loaded with Oncolytic Adenovirus for Active and Targeted Virotherapy of Bladder Cancer.

A unique robotic medical platform is designed by utilizing cell robots as the active "Trojan horse" of oncolytic adenovirus (OA), capable of tumor-selective binding and killing. The OA-loaded cell robots are fabricated by entirely modifying OA-infected 293T cells with cyclic arginine-glycine-aspartic acid tripeptide (cRGD) to specifically bind with bladder cancer cells, followed by asymmetric immobilization of Fe3 O4 nanoparticles (NPs) on the cell surface. OA can replicate in host cells and induce cytolysis to release the virus progeny to the surrounding tumor sites for sustainable infection and oncolysis. The asymmetric coating of magnetic NPs bestows the cell robots with effective movement in various media and wireless manipulation with directional migration in a microfluidic device and bladder mold under magnetic control, further enabling steerable movement and prolonged retention of cell robots in the mouse bladder. The biorecognition of cRGD and robust, controllable propulsion of cell robots work synergistically to greatly enhance their tissue penetration and anticancer efficacy in the 3D cancer spheroid and orthotopic mouse bladder tumor model. Overall, this study integrates cell-based microrobots with virotherapy to generate an attractive robotic system with tumor specificity, expanding the operation scope of cell robots in biomedical community.

Magnetic-Propelled Janus Yeast Cell Robots Functionalized with Metal-Organic Frameworks for Mycotoxin Decontamination.

Cell robots that transform natural cells into active platforms hold great potential to enrich the biomedical prospects of artificial microrobots. Here, we present Janus yeast cell microrobots (JYC-robots) prepared by asymmetrically coating Fe3O4 nanoparticles (NPs) and subsequent in situ growth of zeolitic imidazolate framework-67 (ZIF-67) on the surface of yeast cells. The magnetic actuation relies on the Fe3O4 NPs wrapping. As the compositions of cell robots, the cell wall with abundant polysaccharide coupling with porous and oxidative ZIF-67 can concurrently remove mycotoxin (e.g., zearalenone (ZEN)). The magnetic propulsion accelerates the decontamination efficiency of JYC-robots against ZEN. Although yeast cells with fully coating of Fe3O4 NPs and ZIF-67 (FC-yeasts) show faster movement than JYC-robots, higher toxin-removal efficacy is observed for JYC-robots compared with that of FC-yeasts, reflecting the vital factor of the yeast cell wall in removing mycotoxin. Such design with Janus modification of magnetic NPs (MNPs) and entire coating of ZIF-67 generates active cell robot platform capable of fuel-free propulsion and enhanced detoxification, offering a new formation to develop cell-based robotics system for environmental remediation.

Multifunctional Metal-Organic Framework Exoskeletons Protect Biohybrid Sperm Microrobots for Active Drug Delivery from the Surrounding Threats.

Utilizing spermatozoa as the engine unit of robotic systems at a microscale has brought revolutionized inspirations and strategies to the biomedical community. However, the motility of sperms is impaired by the surrounding threats. For example, the antisperm antibody (AsA) can specifically bind with surface antigens on the sperm membrane and adversely affect their propulsion, hindering the operation of sperm-based microrobots in practical environments. In the present work, we report a biohybrid sperm microrobot by encapsulating sperm cells within metal-organic frameworks (MOFs) and zeolitic imidazolate framework-8 (ZIF-8) nanoparticles (NPs) (ZIFSpermbot), capable of active drug delivery and cytoprotection from the biological threats of AsA. ZIF-8 NPs can be facilely coated on the sperm membrane through complexation with tannic acid. Such cell surface engineering has a negligible impact on sperm motility under optimized conditions. The selective permeability of the resulting porous ZIF-8 wrappings protects ZIFSpermbots from the specific binding of AsA, enabling the preservation of intrinsic propulsion of the sperm engine. Besides, ZIF-8 wrappings sustainably release zinc ions and attenuate the oxidative damage generated in sperm cells, allowing the maintenance of sperm movement. Combining the effective protection of sperm propulsion with the drug-loading capacity of ZIF-8 NPs provides new applicability to ZIFSpermbots in risky surroundings with AsA, exhibiting rapid migration in a microfluidic device for active drug delivery with enhanced therapeutic efficacy due to their retained effective propulsion. Imparting bioengine-based microrobots with multifunctional wrappings holds great promise for designing adaptive cell robots that endure harsh environments toward locally extended and diverse operations, facilitating their use in practical and clinical applications.

Velvet antler polypeptide-loaded polyvinyl alcohol-sodium alginate hydrogels promote the differentiation of neural progenitor cells in 3D towards oligodendrocytes in vitro.

Three-dimensional (3D) culture of neural progenitor cells (NPCs) in hydrogels represents a powerful means for recapitulating neurodevelopment, disease modelling and drug discovery. However, the differentiation of NPCs to oligodendrocytes in 3D scaffolds remains a great challenge. In this study, polyvinyl alcohol (PVA) - sodium alginate (SA) composite hydrogels intended for NPC culture in 3D were fabricated by ionic crosslinking between SA and calcium ions. It was demonstrated that adding PVA to the composite hydrogels resulted in increases in pore size and swelling rate and decreases in elastic moduli as the PVA proportion was enhanced. In addition, the composite hydrogels were biocompatible with mouse NPCs and improved the proliferation of the encapsulated NPCs compared with SA hydrogels. Moreover, when velvet antler polypeptides (VAPs), which were capable of facilitating the differentiation of NPCs to oligodendrocyte fate in 2D, were loaded into PVA-SA hydrogels, NPCs differentiated into neurons, astrocytes and oligodendrocytes, with the presence of VAPs promoting oligodendrogenesis in a dose-dependant manner. The present composite hydrogels provide a suitable scaffold for the construction of neural tissue engineering and neurological disease modelling.

Size-Transformable Hyaluronan Stacked Self-Assembling Peptide Nanoparticles for Improved Transcellular Tumor Penetration and Photo-Chemo Combination Therapy.

Size-transformable nanomedicine has the potential to overcome systemic and local barriers, leading to efficient accumulation and penetration throughout the tumor tissue. However, the design of this type of nanomedicine was seldom based on active targeting and intracellular size transformation. Here, we report an intracellular size-transformable nanosystem, in which small and positively charged nanoparticles (<30 nm) prepared from the self-assembly of an amphiphilic hexadecapeptide derivative was coated by folic acid- and dopamine-decorated hyaluronan (HA) to form large and negatively charged nanoparticles (∼130 nm). This nanosystem has been proven to improve the blood circulation half-life of the drug and prevent premature intravascular drug leakage from the nanocarrier. Once accumulated in the tumor, the nanoparticles were prone to HA- and folic acid-mediated cellular uptake, followed by intracellular size transformation and discharge of transformed small nanoparticles. The size-transformable nanosystem facilitated the transcytosis-mediated tumor penetration and improved the internalization of nanoparticles by cells and the intracellular release of 7-ethyl-10 hydroxycamptothecin. With an indocyanine green derivative as the intrinsic component of the amphiphilic polymer, the nanosystem has exhibited additional theranostic functions: photoacoustic imaging, NIR-laser-induced drug release, and synergistic chemotherapy and phototherapy, leading to a 50% complete cure rate in a subcutaneous B16 melanoma model. This nanosystem with multimodalities and efficient tumor penetration has shown potentials in improving anticancer efficacy.

Enhancing in vivo oral bioavailability of cajaninstilbene acid using UDP-glucuronosyl transferase inhibitory excipient containing self-microemulsion.

Cajaninstilbene acid (CSA) exerts wide pharmacological activities, such as anti-inflammation, hypoglycaemic activity, analgesic effect and cognition improvement. However, it underwent severe phase II metabolism mediated by UDP-glucuronosyltransferase (UGT) in the gastrointestinal (GI) tract after oral administration, affecting its oral bioavailability. In the present study, we utilize UGT inhibitory excipient containing self-microemulsion (SME) delivery system to reduce the production of glucuronide metabolites and increase its oral bioavailability. The present results showed that although similar properties in physiochemical, cytotoxicity, cellular uptake, absorption and transport across rat everted gut sacs between SME-1 (inhibitory excipient containing SME) and SME-2 (control SME, without inhibitory excipient), an improved absolute bioavailability of 57.3 % was conferred by SME-1, significantly higher than the value of 35.4 % by SME-2 and 34.0 % by free CSA. Noticeably, the significantly lower AUC value of CSA glucuronide was determined in rats treated with SME-1 than those either treated with SME-2 or free CSA. Thus, the ability of SME-1 to enhance oral bioavailability of CSA is mainly attributed to the inhibition of phase II metabolism in the GI tract.

Transformable peptide nanoparticles arrest HER2 signalling and cause cancer cell death in vivo.

Human epidermal growth factor receptor 2 (HER2) is overexpressed in >20% of breast cancers. Dimerization of HER2 receptors leads to the activation of downstream signals enabling the proliferation and survival of malignant phenotypes. Owing to the high expression levels of HER2, combination therapies are currently required for the treatment of HER2+ breast cancer. Here, we designed non-toxic transformable peptides that self-assemble into micelles under aqueous conditions but, on binding to HER2 on cancer cells, transform into nanofibrils that disrupt HER2 dimerization and subsequent downstream signalling events leading to apoptosis of cancer cells. The phase transformation of peptides enables specific HER2 targeting, and inhibition of HER2 dimerization blocks the expression of proliferation and survival genes in the nucleus. We demonstrate, in mouse xenofraft models, that these transformable peptides can be used as a monotherapy in the treatment of HER2+ breast cancer.

Effects of Ganoderma, Rhodiola and grape seed extracts on the glucuronidation and oral bioavailability of resveratrol in rats.

Herb extracts were shown to inhibit the activity of UDP-glucuronosyltransferases (UGTs) in vitro. However, the actual in vivo effect of the inhibitory ability on oral bioavailability is yet verified. In this study, resveratrol (RES) was used as a model drug to study the effect of three Chinese herb extracts, Ganoderma, Rhodiola and grape seed, on the in vitro and in vivo inhibition of glucuronidation and the in vivo bioavailability of RES. Overall, although herb extracts might show inhibition on glucuronidation of RES in vitro and in vivo, the inhibition of glucuronidation did not necessarily mean to improve the in vivo bioavailability of RES.

Alginate Hydrogel Modified with a Ligand Interacting with α3ß1 Integrin Receptor Promotes the Differentiation of 3D Neural Spheroids toward Oligodendrocytes in Vitro.

In this study, we established a long-term three-dimensional (3D) culture system by using integrin ligand modified alginate hydrogels to encapsulate and differentiate neural progenitor cells (NPCs) toward oligodendrocyte (OL) lineage cells. The porosity of the hydrogel was optimized by varying the alginate concentrations and then characterized by scanning electronic microscopy (SEM). The surface plasmon resonance (SPR) test was used to confirm the ligand-integrin interactions indicating adherence between the NPC surfaces and the hydrogels. Following encapsulation in the hydrogels, both mouse and human NPC sphere cultures could be maintained up to 90 days. Mouse NPC spheres were differentiated into viable neurons, astrocytes and mature OLs by day 60 in all groups whereas human NPC spheres were differentiated into neurons and later into GFAP positive astrocytes and O4 positive pre-OL within 90 days. The species difference in the timeline of OL development between mouse and human was reflected in this system. The ligand LXY30 interacting with the α3ß1 integrin receptor was more effective in promoting the differentiation of hNPCs to OL lineage cells compared with the ligand LXW64 interacting with the αvß3 integrin receptor, hyaluronic acid interacting with CD44 receptor or without any ligand. This study is the first to differentiate O4+ pre-OLs from hNPCs in a LXY30-α3ß1 (integrin-ligand) modified alginate 3D hydrogel culture. This 3D platform could serve as a valuable tool in disease modeling, drug discovery, and NPC transplantation.

Fluticasone propionate nanosuspensions for sustained nebulization delivery: An in vitro and in vivo evaluation.

This study intended to investigate the in vivo pulmonary fate of intratracheally dosed nanosuspensions of fluticasone propionate (FP). Three FP suspensions, including a microsuspension and two nanosuspensions with different dissolution profiles, were prepared and they exhibited comparable aerodynamic performances after nebulization via a jet nebulizer. Following intratracheal administration to rats, the microsuspension underwent extensive mucociliary clearance, leading to a limited absorption time whereas the nanosuspensions decreased the mucociliary clearance and allowed dissolution rate-limiting and extended pulmonary absorption, resulting in prolonged pulmonary retention and long-acting anti-inflammatory efficacy in a lipopolysaccharide induced lung injury model. Delaying the FP dissolution of a nanosuspension by phospholipid coating increased AUC value in lung tissues to 1.72-fold of a conventional nanosuspension, but led to a decreased pharmacological efficacy. This study demonstrated that inhalable nanosuspensions were a feasible means for the sustained pulmonary delivery of FP and the local anti-inflammatory efficacy was highly dependent on the dissolution profiles.

Multispectral optoacoustic tomography (MSOT) for imaging the particle size-dependent intratumoral distribution of polymeric micelles.

PURPOSE: This study proposes the utilization of multispectral optoacoustic tomography (MSOT) to investigate the intratumoral distribution of polymeric micelles and effect of size on the biodistribution and antitumor efficacy (ATE). MATERIALS AND METHODS: Docetaxel and/or optoacoustic agent-loaded polymeric micelles (with diameters of 22, 48, and 124 nm) were prepared using amphiphilic block copolymers poly (ethylene glycol) methyl ether-block-poly (D,L lactide) (PEG2000-PDLLAx). Subcutaneous 4T1 tumor-bearing mice were monitored with MSOT imaging and IVIS® Spectrum in vivo live imaging after tail vein injection of micelles. The in vivo results and ex vivo confocal imaging results were then compared. Next, ATE of the three micelles was found and compared. RESULTS: We found that MSOT imaging offers spatiotemporal and quantitative information on intratumoral distribution of micelles in living animals. All the polymeric micelles rapidly extravasated into tumor site after intravenous injection, but only the 22-nm micelle preferred to distribute into the inner tumor tissues, leading to a superior ATE than that of 48- and 124-nm micelles. CONCLUSION: This study demonstrated that MSOT is theranostically a powerful imaging modality, offering quantitative information on size-dependent spatiotemporal distribution patterns after the extravasation of nanomedicine from tumor blood vessels.

Improving oral bioavailability of resveratrol by a UDP-glucuronosyltransferase inhibitory excipient-based self-microemulsion.

Self-microemulsifying (SME) drug delivery system has been developed to increase oral bioavailabilities, and inhibitory excipients are capable of improving oral bioavailability by inhibiting enzyme mediated intestinal metabolism. However, the potential of enzyme inhibitory excipients containing SME in boosting resveratrol bioavailability remains largely uninvestigated. In this study, we set out to prepare SME-1 with UGT inhibitory excipients (excipients without inhibitory activities named SME-2 as control) to increase the bioavailability of RES by inhibiting intestinal metabolism. Results demonstrated that similar physicochemical properties such as size, polydistribution index and in vitro release, cellular uptake and permeability in Caco-2 cells as well as in vivo lymphatic distribution between inhibitory SME-1 and non-inhibitory SME-2 were observed. In vivo study demonstrated that the molar ratios of RES-G/RES were 7.25±0.48 and 5.06±2.42 for free drug and SME-2, respectively, and the molar ratio decreased to 0.36±0.10 in SME-1 group. Pharmacokinetic study confirmed that the inhibitory excipients containing SME demonstrated potential in increasing bioavailability of RES from 6.5% for the free RES and 12.9% for SME-2 to 76.1% in SME-1 through modulating the glucuronidation by UGT inhibitory excipients.