Rheumatoid arthritis (RA) is a systemic autoimmune disorder that severely compromises joint health. The primary therapeutic strategy for advanced RA aims to inhibit joint inflammation. However, the nonspecific distribution of pharmacological agents has limited therapeutic efficacy and heightens the risks associated with RA treatment. To address this issue, we developed mesenchymal stem cell (MSC)-based biomimetic liposomes, termed MSCsome, which were composed of a fusion between MSC membranes and liposomes. MSC some with relatively simple preparation method effectively enhanced the targeting efficiency of drug to diseased joints. Interaction between lymphocyte function-associated antigen-1 and intercellular adhesion molecule-1 enhanced the affinity of the MSCsome for polarized macrophages, thereby improving its targeting capability to affected joints. The effective targeted delivery facilitated drug accumulation in joints, resulting in the significant inhibition of the inflammation, as well as protection and repair of the cartilage. In conclusion, this study introduced MSCsome as a promising approach for the effective treatment of advanced RA, providing a novel perspective on targeted drug delivery therapy for inflammatory diseases.

Accumulating evidence suggests that cancer-associated fibroblast (CAF) macroautophagy/autophagy is crucial in tumor development and may be a therapeutic target for pancreatic ductal adenocarcinoma (PDAC). However, the role of CAF autophagy during immune surveillance and cancer immunotherapy is unclear. The present study revealed that the inhibition of CAF autophagy suppresses in vivo tumor development in immune-deficient xenografts. This deletion compromises anti-tumor immunity and anti-tumor efficacy both in vitro and in vivo by upregulating CD274/PDL1 levels in an immune-competent mouse model. A block in CAF autophagy reduced the production of IL6 (interleukin 6), disrupting high desmoplastic TME and decreasing USP14 expression at the transcription level in pancreatic cancer cells. We further identify USP14 as the post-translational factor responsible for downregulating CD274 expression by removing K63 linked-ubiquitination at the K280 residue. Finally, chloroquine diphosphate-loaded mesenchymal stem cell (MSC)-liposomes, by accurately targeting CAFs, inhibited CAF autophagy, improving the efficacy of immunochemotherapy to combat pancreatic cancer.Abbreviation: AIR: adaptive immune resistance; ATRA: all-trans-retinoicacid; CAF: cancer-associated fibroblast; CD274/PDL1: CD274 molecule; CM: conditioned medium; CQ: chloroquine diphosphate; CyTOF: Mass cytometry; FGF2/bFGF: fibroblast growth factor 2; ICB: immune checkpoint blockade; IF: immunofluorescence; IHC: immunohistochemistry; IP: immunoprecipitation; MS: mass spectrometer; MSC: mesenchymal stem cell; PDAC: pancreatic ductal adenocarcinoma; TEM: transmission electron microscopy; TILs: tumor infiltrating lymphocytes; TME: tumor microenvironment; USP14: ubiquitin specific peptidase 14.

Abstract Leukemia is a kind of hematological malignancy originating from bone marrow, which provides essential signals for initiation, progression, and recurrence of leukemia. However, how to specifically deliver drugs to the bone marrow remains elusive. Here, we develop biomimetic vesicles by infusing hematopoietic stem and progenitor cell (HSPC) membrane with liposomes (HSPC liposomes), which migrate to the bone marrow of leukemic mice via hyaluronic acid-CD44 axis. Moreover, the biomimetic vesicles exhibit superior binding affinity to leukemia cells through intercellular cell adhesion molecule-1 (ICAM-1)/integrin β2 (ITGB2) interaction. Further experiments validate that the vesicles carrying chemotherapy drug cytarabine (Ara-C@HSPC-Lipo) markedly inhibit proliferation, induce apoptosis and differentiation of leukemia cells, and decrease number of leukemia stem cells. Mechanically, RNA-seq reveals that Ara-C@HSPC-Lipo treatment induces apoptosis and differentiation and inhibits the oncogenic pathways. Finally, we verify that HSPC liposomes are safe in mice. This study provides a method for targeting bone marrow and treating leukemia.

The hybridization of liposome with stem cell membranes is an emerging technology to prepare the nanovehicle with the capacity of disease-responsive targeting. However, the long-term storage of this hybrid liposome has received limited attention in the literature, which is essential for its potential applicability in the clinic. Therefore, the preservation of long-term activity of stem cell-hybrid liposome using freeze-drying is investigated in the present study. Mesenchymal stem cell-hybrid liposome is synthesized and its feasibility for freeze-drying under different conditions is examined. Results reveal that pre-freezing the hybrid liposome at -20 °C in Tris buffer solution (pH 7.4) containing 10% trehalose can well preserve the liposomal structure for at least three months. Notably, major membrane proteins on the hybrid liposome are protected in this formulation and CXCR4-associated targeting capacity is maintained both in vitro and in vivo. Consequently, the hybrid liposome stored for three months demonstrates a comparable tumor inhibition as the fresh-prepared one. The present study provides the first insights into the long-term storage of stem cell hybrid liposome using lyophilization, which may make an important step forward in enhancing the long-term stability of these promising biomimetic nanovehicle and ease the logistics and the freeze-storage in the potential clinical applications.

Exosomes make a significant contribution during stem cell-based therapy due to the abundant contents. Accumulating evidence implies exosomes can act as potential biological nano agents. We herein propose hypoxic preconditioning for neural stem cells (NSCs) that could produce hypoxic exosomes for efficient treatment of ischemic stroke. Hypoxic preconditioning on NSCs significantly altered the miRNAs encapsulated in exosomes. Notably, hypoxic exosomes could target the injured brain to regulate the microenvironment to inhibit neuroinflammation and promote blood-brain barrier permeability recovery. Additionally, the autologous NSCs in Nestin-CreER mice could be activated by hypoxic exosomes to facilitate nerve regeneration. After hypoxic preconditioning, exosomes further exerted therapeutic effects on both survival (25%) and behavioral outcomes in ischemic stroke mice. Overall, hypoxic preconditioning NSCs can produce effective nano agent and may represent a promising strategy for clinical neurorestorative therapy.

细胞移植疗法方兴未艾,其中干细胞因其分化替代、旁分泌滋养能力、天然炎症归巢能力和低免疫原性优势可促进细胞和组织再生,在再生医学领域具有巨大的潜能.缺血性脑卒中是脑卒中的主要类型,发病后常伴随着不可逆转的神经功能损失和组织坏死.干细胞移植疗法在脑部疾病的治疗中表现出色,除自身的修复作用外,还可以利用干细胞作为药物/基因的靶向递送载体,调节卒中发生后的疾病微环境,促进神经再生.笔者对干细胞的炎症归巢能力及机理、干细胞的药物/基因携载方法和移植干细胞用于缺血性脑卒中的治疗等方面研究进行综述,讨论干细胞移植疗法在临床转化中存在的问题,为基于干细胞的基因传递和缺血性脑卒中的靶向治疗提供参考和新思路.

Understanding the homing dynamics of individual mesenchymal stem cells (MSCs) in physiologically relevant microenvironments is crucial for improving the efficacy of MSC-based therapies for therapeutic and targeting purposes. This study investigates the passive homing behavior of individual MSCs in micropores that mimic interendothelial clefts through predictive computational simulations informed by previous microfluidic experiments. Initially, we quantified the size-dependent behavior of MSCs in micropores and elucidated the underlying mechanisms. Subsequently, we analyzed the shape deformation and traversal dynamics of each MSC. In addition, we conducted a systematic investigation to understand how the mechanical properties of MSCs impact their traversal process. We considered geometric and mechanical parameters, such as reduced cell volume, cell-to-nucleus diameter ratio, and cytoskeletal prestress states. Furthermore, we quantified the changes in the MSC traversal process and identified the quantitative limits in their response to variations in micropore length. Taken together, the computational results indicate the complex dynamic behavior of individual MSCs in the confined microflow. This finding offers an objective way to evaluate the homing ability of MSCs in an interendothelial-slit-like microenvironment.

Pulmonary inflammation is one of the most reported tissue inflammations in clinic. Successful suppression of inflammation is vital to prevent further inevitably fatal lung degeneration. Glucocorticoid hormone, such as methylprednisolone (MP), is the most applied strategy to control the inflammatory progression yet faces the challenge of systemic side effects caused by the requirement of large-dosage and frequent administration. Highly efficient delivery of MP specifically targeted to inflammatory lung sites may overcome this challenge. Therefore, the present study develops an inflammation-targeted biomimetic nanovehicle, which hybridizes the cell membrane of mesenchymal stem cell with liposome, named as MSCsome. This hybrid nanovehicle shows the ability of high targeting specificity toward inflamed lung cells, due to both the good lung endothelium penetration and the high uptake by inflamed lung cells. Consequently, a single-dose administration of this MP-loaded hybrid nanovehicle achieves a prominent treatment of lipopolysaccharide-induced lung inflammation, and negligible treatment-induced side effects are observed. The present study provides a powerful inflammation-targeted nanovehicle using biomimetic strategy to solve the current challenges of targeted inflammation intervention.

Central nervous system (CNS) disorders, including brain tumor, ischemic stroke, Alzheimer's disease, and Parkinson's disease, threaten human health. And the existence of the blood-brain barrier (BBB) hinders the delivery of drugs and the design of drug targeting delivery vehicles. Over the past decades, great interest has been given to cell membrane-based biomimetic vehicles since the rise of targeting drug delivery systems and biomimetic nanotechnology. Cell membranes are regarded as natural multifunction biomaterials, and provide potential for targeting delivery design and modification. Cell membrane-based biomimetic vehicles appear timely with the participation of cell membranes and nanoparticles, and raises new lights for BBB recognition and transport, and effective therapy with its biological multifunction and high biocompatibility. This review summarizes existing challenges in CNS target delivery and recent advances of different kinds of cell membrane-based biomimetic vehicles for effective CNS target delivery, and deliberates the BBB targeting mechanism. It also discusses the challenges and possibility of clinical translation, and presents new insights for development.

Blood-brain barrier (BBB) dis-integrity, a characteristic of extensive inflammatory encephalopathy, provides the access for brain-targeted drug delivery. Inspired from the bioresponsiveness of stem cell, we conceived of new nano-scale delivery strategy via neural stem cell membrane-derived bioresponsive vesicles (NSC-Lipo) for inflamed BBB target delivery. After recombination of neural stem cell membranes with simple liposomes, the functional ligands, especially very late antigen-4 (VLA-4), were entirely engrafted into NSC-Lipo and equipped the NSC-Lipo with "pass order" to the "selective gate". It bestowed the bioresponsive vesicles with selective target the injured brain microvessel endothelial cells (BMECs) and penetrate into the lesion through the vascular cell adhesion molecule-1 (VCAM-1)/VLA-4 interaction in the post-ischemic mice model. The released anti-inflammatory agent, metformin, could reverse the inflammatory response of BMECs and rapidly recovers BBB's integrity. With the repair of BBB's integrity and down regulation of VCAM-1 expression, the targeting ability of bioresponsive vesicles cease to be in force as well. The bioresponsive vesicles led to enhanced survival rate of ischemic stroke mice (from 30 % to 90 %) after just a single injection compared to metformin loaded bare liposomes.

The strategy of using mesenchymal stem cells (MSCs) as a living carrier for active delivery of therapeutic agents targeting tumor sites has been attempted in a wide range of studies to validate the feasibility and efficacy for tumor treatment. This approach reveals powerful tumor targeting and tumor penetration. In addition, MSCs have been confirmed to actively participate in immunomodulation of the tumor microenvironment. Thus, MSCs are not inert delivery vehicles but have a strong impact on the fate of tumor cells. In this review, these active properties of MSCs are addressed to highlight the advantages and challenges of using MSCs for tumor-targeted delivery. In addition, some of the latest examples of using MSCs to carry a variety of anti-tumor agents for tumor-targeted therapy are summarized. Recent technologies to improve the performance and safety of this delivery strategy will be introduced. The advances, applications, and challenges summarized in this review will provide a general understanding of this promising strategy for actively delivering drugs to tumor tissues.

There is evidence to suggest that the primary tumor induces the formation of a pre-metastatic niche in distal organs by stimulating the production of pro-metastatic factors. Given the fundamental role of the pre-metastatic niche in the development of metastases, interruption of its formation would be a promising strategy to take early action against tumor metastasis. Here we report an enzyme-activated assembled peptide FR17 that can serve as a “flame-retarding blanket” in the pre-metastatic niche specifically to extinguish the “fire” of tumor-supportive microenvironment adaption. We show that the in-situ assembled peptide nano-blanket inhibits fibroblasts activation, suppressing the remodeling of the metastasis-supportive host stromal tissue, and reversing vascular destabilization and angiogenesis. Furthermore, we demonstrate that the nano-blanket prevents the recruitment of myeloid cells to the pre-metastatic niche, regulating the immune-suppressive microenvironment. We show that FR17 administration effectively inhibits the formation of the pulmonary pre-metastatic niche and postoperative metastasis, offering a therapeutic strategy against pre-metastatic niche formation.

纳米技术的发展为构建安全高效、精准可控的药物递送系统(drug delivery system,DDS)提供了可能.其中,有机或无机合成纳米载体已被广泛报道并用于肿瘤治疗药物的递送,但部分载体存在易被机体内免疫系统清除、制备过程繁琐和体内安全性较差等问题.近年来,随着生物医学的发展,基于仿生技术的生物膜介导的纳米药物递送系统,因其有机整合了天然生物膜的低免疫原性、肿瘤靶向性和智能纳米载体设计的可调控性、多功能性,有望实现纳米技术在肿瘤靶向治疗上的新突破.本文基于细胞膜仿生技术和纳米医学在肿瘤治疗领域的最新进展,从细胞膜仿生纳米技术的实验基础、膜仿生纳米递药平台的分类和在肿瘤靶向治疗上的应用三方面进行阐述,旨在为仿生智能DDS的设计及其在肿瘤靶向治疗中的发展提供参考.

The clinical translation of stem cells and their extracellular vesicles (EVs)-based therapy for central nervous system (CNS) diseases is booming. Nevertheless, the insufficient CNS delivery and retention together with the invasiveness of current administration routes prevent stem cells or EVs from fully exerting their clinical therapeutic potential. Intranasal (IN) delivery is a possible strategy to solve problems as IN route could circumvent the brain‒blood barrier non-invasively and fit repeated dosage regimens. Herein, we gave an overview of studies and clinical trials involved with IN route and discussed the possibility of employing IN delivery to solve problems in stem cells or EVs-based therapy. We reviewed relevant researches that combining stem cells or EVs-based therapy with IN administration and analyzed benefits brought by IN route. Finally, we proposed possible suggestions to facilitate the development of IN delivery of stem cells or EVs.

Background: Mesenchymal stem cells (MSCs) have been applied as a promising vehicle for tumour-targeted delivery of suicide genes in the herpes simplex virus thymidine kinase (HSV-tk)/ganciclovir (GCV) suicide gene therapy against malignant gliomas. The efficiency of this strategy is largely dependent on the bystander effect, which relies on high suicide gene expression levels and efficient transportation of activated GCV towards glioma cells. However, up to now, the methods to enhance the bystander effect of this strategy in an efficient and safe way are still lacking and new approaches to improve this therapeutic strategy are required. Methods: In this study, MSCs were gene transfected using magnetosome-like ferrimagnetic iron oxide nanochains (MFIONs) to highly express HSV-tk. Both the suicide and bystander effects of HSV-tk expressed MSCs (MSCs-tk) were quantitatively evaluated. Connexin 43 (Cx43) expression by MSCs and glioma cells was measured under different treatments. Intercellular communication between MSCs and C6 glioma cells was examined using a dye transfer assay. Glioma tropism and the bio-distribution of MSCs-tk were observed. Anti-tumour activity was investigated in the orthotopic glioma of rats after intravenous administration of MSCs-tk followed by intraperitoneal injection of GCV. Results: Gene transfection using MFIONs achieved sufficient expression of HSV-tk and triggered Cx43 overexpression in MSCs. These Cx43 overexpressing MSCs promoted gap junction intercellular communication (GJIC) between MSCs and glioma cells, resulting in significantly inhibited growth of glioma through an improved bystander effect. Outstanding tumour targeting and significantly prolonged survival with decreased tumour size were observed after the treatment using MFION-transfected MSCs in glioma model rats. Conclusion: Our results show that iron oxide nanoparticles have the potential to improve the suicide gene expression levels of transfected MSCs, while promoting the GJIC formation between MSCs and tumour cells, which enhances the sensitivity of glioma cells to HSV-tk/GCV suicide gene therapy.

Mesenchymal stem cells (MSCs) are recognized as promising drug delivery vehicles. However, the limitation of drug loading capacity and safety considerations are two obstacles to the further application of MSCs. Here, we report MSC membrane-coated mesoporous silica nanoparticles (MSN@M) that maintain the active stealth and self-positioning drug delivery abilities of MSCs and resolve issues related to MSCs-mediated drug delivery. MSN@M was established through uniformly integrating MSC membrane onto a mesoporous silica nanoparticle (MSN) core by sonication. Reduced clearance of phagocytes mediated by CD47 marker on MSC membrane was observed in vitro, which explained the only ~ 25% clearance rate of MSN@M compared with MSN in vivo within 24 h. MSN@M also showed stronger tumor targeting and penetration ability compared with MSN in HepG2 tumor bearing mice. Simultaneously, MSN@M exhibited strong capacity for drug loading and sustained drug release ability of MSN when loaded with doxorubicin (DOX), the drug loading of MSN@M increased ~ 5 folds compared with MSC membrane. In HepG2 xenograft mice, DOX-loaded MSN@M effectively inhibited the growth of tumors and decreased the side effects of treatment by decreasing the exposure of other tissues to DOX. Consequently, our MSN@M may serve as alternative vehicles for MSCs and provide more options for antitumor treatment.

Cancer nanomedicines that integrate multimodal therapies have been remarkably successful in numerous preclinical models, yet have achieved variable levels of success in the clinic because of tedious and complex manufacturing schemes. Here, we present a facile and versatile strategy to construct photoactivatable self-assembling prodrug cocktail (PSPC) nanoparticles for specific drug activation and cancer chemo-photodynamic therapy. Our strategy involves the PUFAylation of a cytotoxic agent using a polyunsaturated fatty acid (PUFA) via a self-immolation thioketal linkage and a photosensitizer via noncleavable linker. Both PUFAylated prodrugs self-assemble into PSPC therapeutic nanoassemblies without any exogenous excipients. Upon near-infrared (NIR) photoirradiation, the neighboring photosensitizer generates reactive oxygen species (ROS), which spontaneously degrades the thioketal bond to activate the cytotoxic drug cabazitaxel. Consequently, light illumination produces phototoxicity in synchrony with a tumor-specific cascade reaction to accelerate the release of cabazitaxel for potentiating therapeutic synergistic effects on cancer. In multiple mouse models of melanoma xenografts, one of which is a patient-derived xenograft, PSPC nanoassemblies exert a synergistic effect to effectively eradicate tumors. More importantly, the tumor-selective nanotherapy exhibits substantially low systemic toxicity in animals. We propose that the PSPC nanotherapies created using self-assembling small -molecule prodrugs have great therapeutic potential because they enable the spatiotemporal activation of drugs in tumors while alleviating systemic drug exposure and associated toxicities. (C) 2020 Elsevier Ltd. All rights reserved.

The transfer of mitochondria between cells has recently been revealed as a spontaneous way to protect the injured cells. However, the utilization of this natural transfer process for disease treatment is so far limited by its unsatisfactory transfer efficiency and selectivity. Here, we demonstrate that iron oxide nanoparticles (IONPs) can augment the intercellular mitochondrial transfer from human mesenchymal stem cells (hMSCs) selectively to diseased cells, owing to the enhanced formation of connexin 43–containing gap junctional channels triggered by ionized IONPs. In a mouse model of pulmonary fibrosis, the IONP-engineered hMSCs achieve a remarkable mitigation of fibrotic progression because of the promoted intercellular mitochondrial transfer, with no serious safety issues identified. The present study reports a potential method of using IONPs to enable hMSCs for efficient and safe transfer of mitochondria to diseased cells to restore mitochondrial bioenergetics.

Development of injectable nanoparticles for delivery of active anticancer compounds often requires complicated schemes that involve tedious synthetic protocols and nanoformulations. In particular, clinical translation of synergistic nanoparticles that can facilitate multimodal therapies remains a considerable challenge. Herein, we describe a self-assembling, small-molecule nanosystem with unique properties, including near-infrared (NIR) light-responsive drug activation, size transformability, combinatorial synergy, and substantially reduced toxicity. Ligation of anticancer cabazitaxel (CTX) drugs via a reactive oxygen species-activatable thioketal linkage generates a dimeric TKdC prodrug, and subsequent coassembly with a photosensitizer, chlorin e6 (Ce6), forms colloidal-stable nanoassemblies (termed psTKdC NAs). Upon NIR laser irradiation, psTKdC NAs are transformed into smaller size particles and facilitate production of pharmacologically active CTX. Importantly, reactive oxygen species yielded by coassembled Ce6 can synergize with chemotherapy to achieve potent combinatorial effects. In a preclinical orthotopic model of an aggressive, human melanoma patient-derived xenograft (PDX), we show that administration of psTKdC NAs followed by laser irradiation produced durable tumor regression, with the tumors being completely eradicated in three of six PDXs. Furthermore, low systemic toxicity of this smart, photo-activatable nanotherapy was observed in animals. The new self-deliverable combinatorial system addresses essential requirements for high efficacy, safety, and translational capacity and deserves further investigation.

Although enormous attempts are being made to develop synthetic materials for biomedical applications, more and more attention has been paid to bioderived materials due to their natural properties, including mammalian cells, bacteria, and viruses. Attributed to their symmetrical, monodisperse, and polyvalent architectures, viruses present remarkable flexibility in functionalization for biomedical applications. In this review, modification strategies including bioconjugation chemistry, encapsulation, mineralization and genetic engineering, and several related methods for construction of virus-derived materials are introduced. Through rational design, virus-derived materials show great potential in cargo delivery, imaging and therapy. Particularly, virus-derived materials can serve as versatile platforms for immune modulation via various pathways. However, safety concerns of viruses and their immunogenicity are major obstacles for virus-derived materials to be exploited in critical clinical applications, which need to be addressed urgently.