Targeted Cell Delivery Research Articles

Fabrication and Characterization of Collagen–Magnetic Particle Composite Microbeads for Targeted Cell Adhesion and Proliferation

The integration of the biocompatibility of collagen and the remote-control ability of magnetic elements serves as both a cell scaffold and an actuator. We studied the preparation, characterization, and potential applications of collagen–magnetic particle composite microbeads (CMPMBs). The interplay among collagen concentration, particle size, and surface roughness was found to influence cell adhesion and proliferation. Adsorption and desorption tests showed the reversible attachment of the particles to magnetic sheets, enabling precise spatial control and targeted cell delivery. The particles demonstrated their utility as cell carriers, supporting cell migration and proliferation. These findings showcase the potential of CMPMBs as a promising platform for advanced cell delivery and tissue regeneration applications. The ability to fine-tune particle properties and manipulate them using magnetic fields offers new possibilities for creating complex tissue constructs and controlling cellular behavior, which could contribute to the development of more effective regenerative therapies and tissue engineering approaches.

Engineering mannose-functionalized nanostructured lipid carriers by sequential design using hybrid artificial intelligence tools.

Nanostructured lipid carriers (NLCs) hold significant promise as drug delivery systems (DDS) owing to their small size and efficient drug-loading capabilities. Surface functionalization of NLCs can facilitate interaction with specific cell receptors, enabling targeted cell delivery. Mannosylation has emerged as a valuable tool for increasing the ability of nanoparticles to be recognized and internalized by macrophages. Nevertheless, the design and development of functionalized NLC is a complex task that entails the optimization of numerous variables and steps, making the process challenging and time-consuming. Moreover, no previous studies have been focused on evaluating the functionalization efficiency. In this work, hybrid Artificial Intelligence technologies are used to help in the design of mannosylated drug loaded NLCs. Artificial neural networks combined with fuzzy logic or genetic algorithms were employed to understand the particle formation processes and optimize the combinations of variables for the different steps in the functionalization process. Mannose was chemically modified to allow, for the first time, functionalization efficiency quantification and optimization. The proposed sequential methodology has enabled the design of a robust procedure for obtaining stable mannosylated NLCs with a uniform particle size distribution, small particle size (< 100nm), and a substantial positive zeta potential (> 20mV). The incorporation of mannose on the surfaces of these DDS following the established protocols achieved > 85% of functionalization efficiency. This high effectiveness should enhance NLC recognition and internalization by macrophages, thereby facilitating the treatment of chronic inflammatory diseases.

Graft cell expansion from hiPSC-RPE strip after transplantation in primate eyes with or without RPE damage

Clinical studies using suspensions or sheets of human pluripotent cell-derived retinal pigment epithelial cells (hiPSC-RPE) have been conducted globally for diseases such as age-related macular degeneration. Despite being minimally invasive, cell suspension transplantation faces challenges in targeted cell delivery and frequent cell leakage. Conversely, although the RPE sheet ensures targeted delivery with correct cell polarity, it requires invasive surgery, and graft preparation is time-consuming. We previously reported hiPSC-RPE strips as a form of quick cell aggregate that allows for reliable cell delivery to the target area with minimal invasiveness. In this study, we used a microsecond pulse laser to create a local RPE ablation model in cynomolgus monkey eyes. The hiPSC-RPE strips were transplanted into the RPE-ablated and intact sites. The hiPSC-RPE strip stably survived in all transplanted monkey eyes. The expansion area of the RPE from the engrafted strip was larger at the RPE injury site than at the intact site with no tumorigenic growth. Histological observation showed a monolayer expansion of the transplanted RPE cells with the expression of MERTK apically and collagen type 4 basally. The hiPSC-RPE strip is considered a beneficial transplantation option for RPE cell therapy.

Construction of a versatile fusion protein for targeted therapy and immunotherapy.

Antibody (Ab)-based drugs have been widely used in targeted therapies and immunotherapies, leading to significant improvements in tumor therapy. However, the failure of Ab therapy due to the loss of target antigens or Ab modifications that affect its function limits its application. In this study, we expanded the application of antibodies (Abs) by constructing a fusion protein as a versatile tool for Ab-based target cell detection, delivery, and therapy. We first constructed a SpaC Catcher (SpaCC for short) fusion protein that included the C domains of Staphylococcal protein A (SpaC) and the SpyCatcher. SpaCC conjugated with SpyTag-X (S-X) to form the SpaCC-S-X complex, which binds non-covalently to an Ab to form the Ab-SpaCC-S-X protein complex. The "X" can be a variety of small molecules such as fluoresceins, cell-penetrating peptide TAT, Monomethyl auristatin E (MMAE), and DNA. We found that Ab-SpaCC-S-FITC(-TAT) could be used for target cell detection and delivery. Besides, we synthesized the Ab-SpaCC-SN3-MMAE complex by linking Ab with MMAE by SpaCC, which improved the cytotoxicity of small molecule toxins. Moreover, we constructed an Ab-DNA complex by conjugating SpaCC with the aptamer (Ap) and found that Ab-SpaCC-SN3-Ap boosted the tumor-killing function of T-cells by retargeting tumor cells. Thus, we developed a multifunctional tool that could be used for targeted therapies and immunotherapies, providing a cheap and convenient novel drug development strategy.

Injectable cell-laden silk acid hydrogel.

This study presents an injectable cell-laden hydrogel system based on silk acid, a carboxylated derivative of natural silk fibroin, which exhibits promising applications in biomedicine. The hydrogel is produced under physiological conditions (37 °C and pH 7.4) via physical crosslinking. Notably, the hydrogel demonstrates remarkable cytocompatibility, enabling efficient cell encapsulation, and exhibits good injectability. These promising results strongly indicate the potential of silk acid hydrogel for transformative applications, including 3D cell culture, targeted cell delivery, and tissue engineering.

Modularized microrobot with lock-and-detachable modules for targeted cell delivery in bile duct

The magnetic microrobots promise benefits in minimally invasive cell-based therapy. However, they generally suffer from an inevitable compromise between their magnetic responsiveness and biomedical functions. Herein, we report a modularized microrobot consisting of magnetic actuation (MA) and cell scaffold (CS) modules. The MA module with strong magnetism and pH-responsive deformability and the CS module with cell loading-release capabilities were fabricated by three-dimensional printing technique. Subsequently, assembly of modules was performed by designing a shaft-hole structure and customizing their relative dimensions, which enabled magnetic navigation in complex environments, while not deteriorating the cellular functionalities. On-demand disassembly at targeted lesion was then realized to facilitate CS module delivery and retrieval of the MA module. Furthermore, the feasibility of proposed system was validated in an in vivo rabbit bile duct. Therefore, this work presents a modular design–based strategy that enables uncompromised fabrication of multifunctional microrobots and stimulates their development for future cell-based therapy.

Application of a 3D bioprinter: jet technology for 'biopatch' development using cells on hydrogel supports.

Additive manufacturing (3D printing) has been deployed across multiple platforms to fabricate bioengineered tissues. We demonstrate the use of a Thermal Inkjet Pipette System (TIPS) for targeted delivery of cells onto manufactured substrates to design bio-bandages. Two cell lines - HEK 293 (kidney) and K7M2wt (bone) - were applied using TIPS. We demonstrate a novel means for targeted cell delivery to a hydrogel support structure. These cell/support constructs (bio-bandages) had a high viability for survival and growth over extended periods. Combining a flexible biosupport with application of cells via TIPS printing now for the first time allows for custom cell substrate constructs with various densities to be deployed for regenerative medicine applications.

Targeted cell delivery of mesenchymal stem cell therapy for cardiovascular disease applications: a review of preclinical advancements.

Cardiovascular diseases (CVD) continue to be the leading cause of morbidity and mortality globally and claim the lives of over 17 million people annually. Current management of CVD includes risk factor modification and preventative strategies including dietary and lifestyle changes, smoking cessation, medical management of hypertension and cholesterol lipid levels, and even surgical revascularization procedures if needed. Although these strategies have shown therapeutic efficacy in reducing major adverse cardiovascular events such as heart attack, stroke, symptoms of chronic limb-threatening ischemia (CLTI), and major limb amputation significant compliance by patients and caregivers is required and off-target effects from systemic medications can still result in organ dysfunction. Stem cell therapy holds major potential for CVD applications but is limited by the low quantities of cells that are able to traffic to and engraft at diseased tissue sites. New preclinical investigations have been undertaken to modify mesenchymal stem cells (MSCs) to achieve targeted cell delivery after systemic administration. Although previous reviews have focused broadly on the modification of MSCs for numerous local or intracoronary administration strategies, here we review recent preclinical advances related to overcoming challenges imposed by the high velocity and dynamic flow of the circulatory system to specifically deliver MSCs to ischemic cardiac and peripheral tissue sites. Many of these technologies can also be applied for the targeted delivery of other types of therapeutic cells for treating various diseases.

A Neurospheroid-Based Microrobot for Targeted Neural Connections in a Hippocampal Slice.

Functional restoration by the re-establishment of cellular or neural connections remains a major challenge in targeted cell therapy and regenerative medicine. Recent advances in magnetically powered microrobots have shown potential for use in controlled and targeted cell therapy. In this study, a magnetic neurospheroid (Mag-Neurobot) that can form both structural and functional connections with an organotypic hippocampal slice (OHS) is assessed using an ex vivo model as a bridge toward in vivo application. The Mag-Neurobot consists of hippocampal neurons and superparamagnetic nanoparticles (SPIONs); it is precisely and skillfully manipulated by an external magnetic field. Furthermore, the results of patch-clamp recordings of hippocampal neurons indicate that neither the neuronal excitabilities nor the synaptic functions of SPION-loaded cells are significantly affected. Analysis of neural activity propagation using high-density multi-electrode arrays shows that the delivered Mag-Neurobot is functionally connected with the OHS. The applications of this study include functional verification for targeted cell delivery through the characterization of novel synaptic connections and the functionalities of transported and transplanted cells. The success of the Mag-Neurobot opens up new avenues of research and application; it offers a test platform for functional neural connections and neural regenerative processes through cell transplantation.

Magnetically Actuated Microscaffold with Controllable Magnetization and Morphology for Regeneration of Osteochondral Tissue.

Magnetic microscaffolds capable of targeted cell delivery have been developed for tissue regeneration. However, the microscaffolds developed so far with similar morphologies have limitations for applications to osteochondral disease, which requires simultaneous treatment of the cartilage and subchondral bone. This study proposes magnetically actuated microscaffolds tailored to the cartilage and subchondral bone for osteochondral tissue regeneration, named magnetically actuated microscaffolds for cartilage regeneration (MAM-CR) and for subchondral bone regeneration (MAM-SBR). The morphologies of the microscaffolds were controlled using a double emulsion and microfluidic flow. In addition, due to their different sizes, MAM-CR and MAM-SBR have different magnetizations because of the different amounts of magnetic nanoparticles attached to their surfaces. In terms of biocompatibility, both microscaffolds were shown to grow cells without toxicity as potential cell carriers. In magnetic actuation tests of the microscaffolds, the relatively larger MAM-SBR moved faster than the MAM-CR under the same magnetic field strength. In a feasibility test, the magnetic targeting of the microscaffolds in 3D knee cartilage phantoms showed that the MAM-SBR and MAM-CR were sequentially moved to the target sites. Thus, the proposed magnetically actuated microscaffolds provide noninvasive treatment for osteochondral tissue disease.

Cellular modifications and biomaterial design to improve mesenchymal stem cell transplantation.

Research has advanced considerably since the first clinical trial of human mesenchymal stem cells (MSCs) in the early 1990s. During this period, our understanding of MSC biology and our ability to expand and manipulate these cells have provided hope for the repair of damaged tissues due to illness or injury. MSCs have conventionally been injected systemically or locally into target tissue; however, inconsistent cell homing and engraftment efficiencies represent a major bottleneck that has led to mixed results in clinical studies. To overcome these issues, MSCs have been pre-conditioned with biomolecules, genetically altered, or surface engineered to enhance their homing and engraftment capabilities. In parallel, a variety of cell-encapsulating materials have been designed to improve cell delivery and post-transplantation survival and function. In this review, we discuss the current strategies that have been employed on cultured MSCs to improve targeted cell delivery and retention for tissue repair. We also discuss the advances in injectable and implantable biomaterial technologies that drive the success of MSC-based therapies in regenerative medicine. Multi-faceted approaches combining cellular modification and cell-instructive material design can pave the way for efficient and robust stem cell transplantation for superior therapeutic outcomes.

Computer Aided Development of Nucleic Acid Applications in Nanotechnologies.

Utilization of nucleic acids (NAs) in nanotechnologies and nanotechnology-related applications is a growing field with broad application potential, ranging from biosensing up to targeted cell delivery. Computer simulations are useful techniques that can aid design and speed up development in this field. This review focuses on computer simulations of hybrid nanomaterials composed of NAs and other components. Current state-of-the-art molecular dynamics simulations, empirical force fields (FFs), and coarse-grained approaches for the description of deoxyribonucleic acid and ribonucleic acid are critically discussed. Challenges in combining biomacromolecular and nanomaterial FFs are emphasized. Recent applications of simulations for modeling NAsand their interactions with nano- and biomaterials are overviewed in the fields of sensing applications, targeted delivery, and NAtemplated materials. Future perspectives of development are also highlighted.

415.5: A Proof of Principle Study of Cell Targeted Delivery of SiRNA Guided by Innate Repair Receptor EPOR/betacR Highly Expressed by Injured Tubular Epithelial Cells in Porcine Kidneys Subjected to Extended Cold Ischaemic Times

Introduction: Small interfering RNA (siRNA) has been used in biological models for disease modification. Whilst challenges remain with targeted cell delivery, caspase-3, an executing enzyme of apoptosis and inflammation, plays a crucial role in acute kidney injury. Using caspase-3 siRNA or erythropoietin derived peptide CHBP, we have demonstrated renoprotection against ischaemia-reperfusion injury in isolated kidney preservation, and further applied the conjugate of both. Methods: Porcine kidneys (n = 3) subjected to 10 minutes of warm ischemia were retrieved and perfused with 500 mL hyperosmolar citrate. In comparison with the control (Kidney 1) caspase-3 siRNA-HBSP (Kidney 2) or CHBP (Kidney 3) conjugate was administered into the kidney and autologous blood, and stored for 22 hoursin ice. Organs were then preserved by normothermic perfusion (NP) for 3 hours using clinical-grade cardiopulmonary bypass. Functional parameters were recorded, and kidney biopsies were taken at time zero (pre-perfusion) and hourly intervals following NP. Results: Preliminary findings showed increased arterial flow rate and urine output together with neutralised perfusate pH in the kidneys (2 and 3) receiving both conjugates compared to the control. Conclusion: Improved physiological outcomes in kidneys subjected to the novel agent treatment suggest protective effects against ischaemia. We hypothesise outcomes should be transferrable to human kidneys, which may facilitate the use of marginal kidneys following prolonged ischaemia, otherwise deemed unsuitable for transplantation. Renal histological and molecular studies of the effect of the agent are underway.

O083 A proof of principle study of cell targeted delivery of sirna guided by innate repair receptor epor/βcr highly expressed by injured tubular epithelial cells in porcine kidneys subjected to extended cold ischaemia times

Abstract Introduction Small interfering RNA (siRNA) has been used in biological models for disease modification. Whilst challenges remain with targeted cell delivery, caspase-3, an executing enzyme of apoptosis and inflammation, plays a crucial role in acute kidney injury. Using caspase-3 siRNA or erythropoietin derived peptide CHBP, we have demonstrated renoprotection against ischaemia-reperfusion injury in isolated kidney preservation, and further applied the conjugate of both. Methods Porcine kidneys (n = 3) subjected to 10 minutes of warm ischemia were retrieved and perfused with 500 mL hyperosmolar citrate. In comparison with the control (Kidney 1) caspase-3 siRNAHBSP (Kidney 2) or CHBP (Kidney 3) conjugate was administered into the kidney and autologous blood and stored for 22 hours in ice. Organs were then preserved by normothermic perfusion (NP) for 3 hours using clinical-grade cardiopulmonary bypass. Functional parameters were recorded, and kidney biopsies were taken at time zero (pre-perfusion) and hourly intervals following NP. Results Preliminary findings showed increased arterial flow rate and urine output together with neutralised perfusate pH in the kidneys (2 and 3) receiving both conjugates compared to the control. Conclusion Improved physiological outcomes in kidneys subjected to the novel agent treatment suggest protective effects against ischaemia. We hypothesise outcomes should be transferrable to human kidneys, which may facilitate the use of marginal kidneys following prolonged ischaemia, otherwise deemed unsuitable for transplantation. Renal histological and molecular studies of the effect of the agent are underway. Take-home message Despite a small sample, this pilot proof of principle study suggests that caspase-3 inhibitors may have a role in limiting the detrimental effects of ischaemia on renal tissues subjected to prolonged cold ischaemic times. It is hoped that this may be beneficial if replicated in the human kidney model at increasing the deceased donor organ pool by enabling use of marginal kidneys subjected to prolonged ischaemic times.

Tetraethylenepentamine-Coated β Cyclodextrin Nanoparticles for Dual DNA and siRNA Delivery.

Nucleic acid reagents, including plasmid-encoded genes and small interfering RNA (siRNA), are promising tools for validating gene function and for the development of therapeutic agents. Native β-cyclodextrins (BCDs) have limited efficiency in gene delivery due to their instable complexes with nucleic acid. We hypothesized that cationic BCD nanoparticles could be an efficient carrier for both DNA and siRNA. Tetraethylenepentamine-coated β-cyclodextrin (TEPA-BCD) nanoparticles were synthesized, characterized, and evaluated for targeted cell delivery of plasmid DNA and siRNA. The cationic TEPA coating provided ideal zeta potential and effective nucleic acid binding ability. When transfecting plasmid encoding green fluorescent protein (GFP) by TEPA-BCD, excellent GFP expression could be achieved in multiple cell lines. In addition, siRNA transfected by TEPA-BCD suppressed target GFP gene expression. We showed that TEPA-BCD internalization was mediated by energy-dependent endocytosis via both clathrin-dependent and caveolin-dependent endocytic pathways. TEPA-BCD nanoparticles provide an effective means of nucleic acid delivery and can act as potential carriers in future pharmaceutical application.

An Unrevealed Molecular Function of Corannulene Buckybowl Glycoconjugates in Selective Tumor Annihilation by Targeting the Cancer-Specific Warburg Effect.

The biomedical application of corannulene π‐bowls is historically limited by low solubility and bioavailability despite the potential in their unique electronic properties for new functional materials. Herein, the unexpected role and molecular mechanism of Corranulene π‐bowls are uncovered in biomedical applications as an effective anticancer agent for Warburg effect mediated selective tumor targeting. The corannulene triazolyl monosaccharides Cor‐sugars exhibit highly potent cytotoxicity against human cancer cells and effectively inhibit xenograft growth of hyperglycolytic tumors. Particularly, the galactose‐conjugated Cor‐gal exhibits superior in vivo anticancer efficacy in A549 tumor models with outstanding safety profile compared to doxorubicin. Moreover, the combined treatment of Cor‐gal with immune checkpoint inhibitor results in an effective synergy in treating H460 human lung carcinoma. An uptake mechanism study reveals that Cor‐sugars exploit tumor‐specific glucose transporter glucose transporter 1 (GLUT1) for targeted cell delivery and intra‐tumoral accumulation through the cancer‐specific Warburg effect. Their significant anticancer activity is attributed to multiphasic DNA‐binding and cell cycle alteration effects. This study uncovers new molecular properties of corannulene buckybowl and enabling their potential new applications in biomedical engineering.

The Impact of Cerebral Perfusion on Mesenchymal Stem Cells Distribution after Intra-Arterial Transplantation: A Quantitative MR Study.

Intra-arterial (IA) mesenchymal stem cells (MSCs) transplantation providing targeted cell delivery to brain tissue is a promising approach to the treatment of neurological disorders, including stroke. Factors determining cell distribution after IA administration have not been fully elucidated. Their decoding may contribute to the improvement of a transplantation technique and facilitate translation of stroke cell therapy into clinical practice. The goal of this work was to quantitatively assess the impact of brain tissue perfusion on the distribution of IA transplanted MSCs in rat brains. We performed a selective MR-perfusion study with bolus IA injection of gadolinium-based contrast agent and subsequent IA transplantation of MSCs in intact rats and rats with experimental stroke and evaluated the correlation between different perfusion parameters and cell distribution estimated by susceptibility weighted imaging (SWI) immediately after cell transplantation. The obtained results revealed a certain correlation between the distribution of IA transplanted MSCs and brain perfusion in both intact rats and rats with experimental stroke with the coefficient of determination up to 30%. It can be concluded that the distribution of MSCs after IA injection can be partially predicted based on cerebral perfusion data, but other factors requiring further investigation also have a significant impact on the fate of transplanted cells.

The effect of the surface coating of human adipose-derived stem cells by various GAGs on the biodistribution of them upon intravenous administration

Glycosaminoglycans (GAGs) are essential for cell-cell and cell-ECM interactions. Unique structures of GAGs provide high affinities to specific cell receptors. Especially, hyaluronic acid (HA), chondroitin sulfate (CS), and heparin are known to have affinities to the liver sinusoidal endothelial cells (LSECs), so they have been utilized as a ligand for liver targeting nanoparticle systems. In this study, we compared different GAGs as a targeted cell delivery ligand by using lipid-conjugated GAGs. Conjugated lipids of GAGs could provide a stable coating over 2 days on the surface of human adipose-derived stem cells (hADSCs) by physical insertion. The hADSCs coated by different GAGs were intravenously injected into mice, and the biodistribution of cells was analyzed by an In Vivo Imaging System (IVIS) to compare the effect of various GAGs on the modulation of biodistribution of stem cells. The results showed that all three GAGs could provide less entrapment in the lung but enhanced accumulation in the liver and spleen. Especially, HA- and heparin coating on hADSCs showed a 1.5-fold higher accumulation than CS-coating on hADSCs in the liver and spleen. Thus, lipid-conjugated HA and heparin are potentially useful coating materials for the liver or spleen-targeted delivery system of therapeutic stem cells.

Microneedle-based technology for cell therapy: current status and future directions.

With the growing technological innovations in medical treatments, cell-based therapies hold great potential as efficient tools against various previously incurable diseases by restoring or altering the function of certain sets of cells. Along this line, an essential factor to determine the success of cell therapy is the choice of cell delivery strategy. In recent years, a novel trend is blooming in the application of microneedle systems, which are based on the miniaturization of multiple needles within a patch to the micrometer dimensions, aimed at the delivery of therapeutic cells to the target site with high efficiency and in a minimally invasive manner. This review aims to demonstrate the advantages of exploiting microneedle-based technology as a new tool for cell therapy. The advancements of microneedle-based strategies for cell delivery are summarized in terms of two categories: cell-free and cell-loaded microneedle systems. The majority of research on microneedle-based cell therapy has shown promising results for tissue regeneration, cancer immunotherapy, skin immune monitoring and targeted cell delivery. Finally, current challenges and future perspectives toward the development and application of microneedles for cell therapy are also discussed.

A homogeneous high-DAR antibody-drug conjugate platform combining THIOMAB antibodies and XTEN polypeptides.

The antibody–drug conjugate (ADC) is a well-validated modality for the cell-specific delivery of small molecules with impact expanding rapidly beyond their originally-intended purpose of treating cancer. However, antibody-mediated delivery (AMD) remains inefficient, limiting its applicability to targeting highly potent payloads to cells with high antigen expression. Maximizing the number of payloads delivered per antibody is one key way in which delivery efficiency can be improved, although this has been challenging to carry out; with few exceptions, increasing the drug-to-antibody ratio (DAR) above ∼4 typically destroys the biophysical properties and in vivo efficacy for ADCs. Herein, we describe the development of a novel bioconjugation platform combining cysteine-engineered (THIOMAB) antibodies and recombinant XTEN polypeptides for the unprecedented generation of homogeneous, stable “TXCs” with DAR of up to 18. Across three different bioactive payloads, we demonstrated improved AMD to tumors and Staphylococcus aureus bacteria for high-DAR TXCs relative to conventional low-DAR ADCs.