Biomaterials as vectors for the delivery of CRISPR-Cas9

Non-viral vector-based genome editing for cancer immunotherapy

Despite the exciting promise of cancer immunotherapy in the clinic, immune checkpoint blockade therapy and T cell-based therapies are often associated with low response rates, intrinsic and adaptive immune resistance, and systemic side effects. CRISPR-Cas-based genome editing appears to be an effective strategy to overcome these unmet clinical needs. As a safer delivery platform for the CRISPR-Cas system, non-viral nanoformulations have been recently explored to target tumor cells and immune cells, aiming to improve cancer immunotherapy on a gene level. In this review, we summarized the efforts of non-viral vector-based CRISPR-Cas-mediated genome editing in tumor cells and immune cells for cancer immunotherapy. Their design rationale and specific applications were highlighted.

Comparing chemical transfection, electroporation, and lentiviral vector transduction to achieve optimal transfection conditions in the Vero cell line

BACKGROUND

Transfection is an important analytical method for studying gene expression in the cellular environment. There are some barriers to efficient DNA transfection in host cells, including circumventing the plasma membrane, escaping endosomal compartmentalization, autophagy, immune sensing pathways, and translocating the nuclear envelope. Therefore, it would be very useful to introduce an optimum transfection approach to achieve a high transfection efficiency in the Vero cell line. The aim of this study was to compare various transfection techniques and introduce a highly efficient method for gene delivery in Vero cells.

METHODS

In the current study, three transfection methods were used, including chemical transfection, electroporation, and lentiviral vector transduction, to obtain the optimum transfection conditions in the Vero cell line. Vero cells were cultured and transfected with chemical transfection reagents, electroporation, or HIV-1-based lentivectors under different experimental conditions. Transfection efficiency was assessed using flow cytometry and fluorescence microscopy to detect GFP-positive cells.

RESULTS

Among the tested methods, TurboFect™ chemical transfection exhibited the highest efficiency. Optimal transfection conditions were achieved using 1 µg DNA and 4 µL TurboFect™ in 6 × 104 Vero cells.

CONCLUSION

TurboFect™, a cationic polymer transfection reagent, demonstrated superior transfection efficiency in Vero cells compared with electroporation and lentivirus particles, and is the optimal choice for chemical transfection in the Vero cell line.

Biomaterial-Based CRISPR/Cas9 Delivery Systems for Tumor Treatment

CRISPR/Cas9 gene editing technology is characterized by high specificity and efficiency, and has been applied to the treatment of human diseases, especially tumors involving multiple genetic modifications. However, the clinical application of CRISPR/Cas9 still faces some major challenges, the most urgent of which is the development of optimized delivery vectors. Biomaterials are currently the best choice for use in CRISPR/Cas9 delivery vectors owing to their tunability, biocompatibility, and efficiency. As research on biomaterial vectors continues to progress, hope for the application of the CRISPR/Cas9 system for clinical oncology therapy builds. In this review, we first detail the CRISPR/Cas9 system and its potential applications in tumor therapy. Then, we introduce the different delivery forms and compare the physical, viral, and non-viral vectors. In addition, we analyze the characteristics of different types of biomaterial vectors. We further review recent research progress in the use of biomaterials as vectors for CRISPR/Cas9 delivery to treat specific tumors. Finally, we summarize the shortcomings and prospects of biomaterial-based CRISPR/Cas9 delivery systems.

In Vitro Prostate Cancer Treatment via CRISPR-Cas9 Gene Editing Facilitated by Polyethyleneimine-Derived Graphene Quantum Dots

CRISPR-Cas9 is a programmable gene editing tool with a promising potential for cancer gene therapy. This therapeutic function is enabled in the present work via the non-covalent delivery of CRISPR ribonucleic protein (RNP) by cationic glucosamine/PEI-derived graphene quantum dots (PEI-GQD) that aid in overcoming physiological barriers and tracking genes of interest. PEI-GQD/RNP complex targeting the TP53 mutation overexpressed in ~50% of cancers successfully produces its double-stranded breaks in solution and in PC3 prostate cancer cells. Restoring this cancer "suicide" gene can promote cellular repair pathways and lead to cancer cell apoptosis. Its repair to the healthy form performed by simultaneous PEI-GQD delivery of CRISPR RNP and a gene repair template leads to a successful therapeutic outcome: 40% apoptotic cancer cell death, while having no effect on non-cancerous HeK293 cells. The translocation of PEI-GQD/RNP complex into PC3 cell cytoplasm is tracked via GQD intrinsic fluorescence, while EGFP-tagged RNP is detected in the cell nucleus, showing the successful detachment of the gene editing tool upon internalization. Using GQDs as non-viral delivery and imaging agents for CRISPR-Cas9 RNP sets the stage for image-guided cancer-specific gene therapy.

GMOs or non-GMOs? The CRISPR Conundrum

CRISPR-Cas9, the "genetic scissors", is being presaged as a revolutionary technology, having tremendous potential to create designer crops by introducing precise and targeted modifications in the genome to achieve global food security in the face of climate change and increasing population. Traditional genetic engineering relies on random and unpredictable insertion of isolated genes or foreign DNA elements into the plant genome. However, CRISPR-Cas based gene editing does not necessarily involve inserting a foreign DNA element into the plant genome from different species but introducing new traits by precisely altering the existing genes. CRISPR edited crops are touching markets, however, the world community is divided over whether these crops should be considered genetically modified (GM) or non-GM. Classification of CRISPR edited crops, especially transgene free crops as traditional GM crops, will significantly affect their future and public acceptance in some regions. Therefore, the future of the CRISPR edited crops is depending upon their regulation as GM or non-GMs, and their public perception. Here we briefly discuss how CRISPR edited crops are different from traditional genetically modified crops. In addition, we discuss different CRISPR reagents and their delivery tools to produce transgene-free CRISPR edited crops. Moreover, we also summarize the regulatory classification of CRISPR modifications and how different countries are regulating CRISPR edited crops. We summarize that the controversy of CRISPR-edited plants as GM or non-GM will continue until a universal, transparent, and scalable regulatory framework for CRISPR-edited plants will be introduced worldwide, with increased public awareness by involving all stakeholders.

Recognizing CRISPR as the new age disease-modifying drug: Strategies to bioengineer CRISPR/Cas for direct in vivo delivery

Clustered regularly interspaced short palindromic repeats (CRISPR) have established itself as a frontier technology in genetic engineering. Researchers have successfully used the CRISPR/Cas system as precise gene editing tools and have further expanded their scope beyond both imaging and diagnostic applications. The most prominent utility of CRISPR is its capacity for gene therapy, serving as the contemporary, disease-modifying drug at the genetic level of human medical disorders. Correcting these diseases using CRISPR-based gene editing has developed to the extent of preclinical trials and possible patient treatments. A major impediment in actualizing this is the complications associated with in vivo delivery of the CRISPR/Cas complex. Currently, only the viral vectors (e.g., lentivirus) and non-viral encapsulation (e.g., lipid particles, polymer-based, and gold nanoparticles) techniques have been extensively reviewed, neglecting the efficiency of direct delivery. However, the direct delivery of CRISPR/Cas for in vivo gene editing therapies is an intricate process with numerous drawbacks. Hence, this paper discusses in detail both the need and the strategies that can potentially improve the direct delivery aspects of CRISPR/Cas biomolecules for gene therapy of human diseases. Here, we focus on enhancing the molecular and functional features of the CRISPR/Cas system for targeted in vivo delivery such as on-site localization, internalization, reduced immunogenicity, and better in vivo stability. We additionally emphasize the CRISPR/Cas complex as a multifaceted, biomolecular vehicle for co-delivery with therapeutic agents in targeted disease treatments. The delivery formats of efficient CRISPR/Cas systems for human gene editing are also briefly elaborated.

Nanotechnology-enabled gene delivery for cancer and other genetic diseases

INTRODUCTION

Despite gene therapy is ideal for genetic abnormality-related diseases, the easy degradation, poor targeting, and inefficiency in entering targeted cells are plaguing the effective delivery of gene therapy. Viral and non-viral vectors have been used for delivering gene therapeutics in vivo by safeguarding nucleic acid agents to target cells and to reach the specific intracellular location. A variety of nanotechnology-enabled safe and efficient systems have been successfully developed to improve the targeting ability for effective therapeutic delivery of genetic drugs.

AREAS COVERED

In this review, we outline the multiple biological barriers associated with gene delivery process, and highlight recent advances to gene therapy strategy in vivo, including gene correction, gene silencing, gene activation and genome editing. We point out current developments and challenges exist of non-viral and viral vector systems in association with chemical and physical gene delivery technologies and their potential for the future.

EXPERT OPINION

This review focuses on the opportunities and challenges to various gene therapy strategy, with specific emphasis on overcoming the challenges through the development of biocompatibility and smart gene vectors for potential clinical application.

Application of CRISPR/Cas9 Technology in Cancer Treatment: A Future Direction

Gene editing, especially with clustered regularly interspaced short palindromic repeats associated protein 9 (CRISPR-Cas9), has advanced gene function science. Gene editing's rapid advancement has increased its medical/clinical value. Due to its great specificity and efficiency, CRISPR/Cas9 can accurately and swiftly screen the whole genome. This simplifies disease-specific gene therapy. To study tumor origins, development, and metastasis, CRISPR/Cas9 can change genomes. In recent years, tumor treatment research has increasingly employed this method. CRISPR/Cas9 can treat cancer by removing genes or correcting mutations. Numerous preliminary tumor treatment studies have been conducted in relevant fields. CRISPR/Cas9 may treat gene-level tumors. CRISPR/Cas9-based personalized and targeted medicines may shape tumor treatment. This review examines CRISPR/Cas9 for tumor therapy research, which will be helpful in providing references for future studies on the pathogenesis of malignancy and its treatment.

In vivo delivery of CRISPR-Cas9 genome editing components for therapeutic applications

Since its mechanism discovery in 2012 and the first application for mammalian genome editing in 2013, CRISPR-Cas9 has revolutionized the genome engineering field and created countless opportunities in both basic science and translational medicine. The first clinical trial of CRISPR therapeutics was initiated in 2016, which employed ex vivo CRISPR-Cas9 edited PD-1 knockout T cells for the treatment of non-small cell lung cancer. So far there have been dozens of clinical trials registered on ClinicalTrials.gov in regard to using the CRISPR-Cas9 genome editing as the main intervention for therapeutic applications; however, most of these studies use ex vivo genome editing approach, and only a few apply the in vivo editing strategy. Compared to ex vivo editing, in vivo genome editing bypasses tedious procedures related to cell isolation, maintenance, selection, and transplantation. It is also applicable to a wide range of diseases and disorders. The main obstacles to the successful translation of in vivo therapeutic genome editing include the lack of safe and efficient delivery system and safety concerns resulting from the off-target effects. In this review, we highlight the therapeutic applications of in vivo genome editing mediated by the CRISPR-Cas9 system. Following a brief introduction of the history, biology, and functionality of CRISPR-Cas9, we showcase a series of exemplary studies in regard to the design and implementation of in vivo genome editing systems that target the brain, inner ear, eye, heart, liver, lung, muscle, skin, immune system, and tumor. Current challenges and opportunities in the field of CRISPR-enabled therapeutic in vivo genome editing are also discussed.

Biomaterial Design Inspired by Regenerative Research Organisms

The efficacy of implanted biomaterials is largely dependent on the response of the host's immune and stromal cells. Severe foreign body response (FBR) can impede the integration of the implant into the host tissue and compromise the intended mechanical and biochemical function. Many features of FBR, including late-stage fibrotic encapsulation of implants, parallel the formation of fibrotic scar tissue after tissue injury. Regenerative organisms like zebrafish and salamanders can avoid fibrosis after injury entirely, but FBR in these research organisms is rarely investigated because their immune competence is much lower than humans. The recent characterization of a regenerative mammal, the spiny mouse (Acomys), has inspired us to take a closer look at cellular regulation in regenerative organisms across the animal kingdom for insights into avoiding FBR in humans. Here, we highlight how major features of regeneration, such as blastema formation, macrophage polarization, and matrix composition, can be modulated across a range of regenerative research organisms to elucidate common features that may be harnessed to minimize FBR. Leveraging a deeper understanding of regenerative biology for biomaterial design may help to reduce FBR and improve device integration and performance.

Cas13d knockdown of lung protease Ctsl prevents and treats SARS-CoV-2 infection

SARS-CoV-2 entry into cells requires specific host proteases; however, no successful in vivo applications of host protease inhibitors have yet been reported for treatment of SARS-CoV-2 pathogenesis. Here we describe a chemically engineered nanosystem encapsulating CRISPR-Cas13d, developed to specifically target lung protease cathepsin L (Ctsl) messenger RNA to block SARS-CoV-2 infection in mice. We show that this nanosystem decreases lung Ctsl expression in normal mice efficiently, specifically and safely. We further show that this approach extends survival of mice lethally infected with SARS-CoV-2, correlating with decreased lung virus burden, reduced expression of proinflammatory cytokines/chemokines and diminished severity of pulmonary interstitial inflammation. Postinfection treatment by this nanosystem dramatically lowers the lung virus burden and alleviates virus-induced pathological changes. Our results indicate that targeting lung protease mRNA by Cas13d nanosystem represents a unique strategy for controlling SARS-CoV-2 infection and demonstrate that CRISPR can be used as a potential treatment for SARS-CoV-2 infection.

Biopolymeric Prodrug Systems as Potential Antineoplastic Therapy

Nowadays, cancer represents a major public health issue, a substantial economic issue, and a burden for society. Limited by numerous disadvantages, conventional chemotherapy is being replaced by new strategies targeting tumor cells. In this context, therapies based on biopolymer prodrug systems represent a promising alternative for improving the pharmacokinetic and pharmacologic properties of drugs and reducing their toxicity. The polymer-directed enzyme prodrug therapy is based on tumor cell targeting and release of the drug using polymer–drug and polymer–enzyme conjugates. In addition, current trends are oriented towards natural sources. They are biocompatible, biodegradable, and represent a valuable and renewable source. Therefore, numerous antitumor molecules have been conjugated with natural polymers. The present manuscript highlights the latest research focused on polymer–drug conjugates containing natural polymers such as chitosan, hyaluronic acid, dextran, pullulan, silk fibroin, heparin, and polysaccharides from Auricularia auricula.

Nanocarriers: A novel strategy for the delivery of CRISPR/Cas systems

In recent decades, clustered regularly interspaced short palindromic repeat/CRISPR-associated protein (CRISPR/Cas) has become one of the most promising genome-editing tools for therapeutic purposes in biomedical and medical applications. Although the CRISPR/Cas system has truly revolutionized the era of genome editing, the safe and effective delivery of CRISPR/Cas systems represents a substantial challenge that must be tackled to enable the next generation of genetic therapies. In addition, there are some challenges in the in vivo delivery to the targeted cells/tissues. Nanotechnology-based drug delivery systems can be employed to overcome this issue. This review discusses different types and forms of CRISPR/Cas systems and the current CRISPR/Cas delivery systems, including non-viral carriers such as liposomes, polymeric, and gold particles. The focus then turns to the viral nanocarriers which have been recently used as a nanocarrier for CRISPR/Cas delivery.

In vivo Delivery Tools for Clustered Regularly Interspaced Short Palindromic Repeat/Associated Protein 9-Mediated Inhibition of Hepatitis B Virus Infection: An Update

Chronic hepatitis B virus (HBV) infection remains a major global health problem despite the availability of an effective prophylactic HBV vaccine. Current antiviral therapies are unable to fully cure chronic hepatitis B (CHB) because of the persistent nature of covalently closed circular DNA (cccDNA), a replicative template for HBV, which necessitates the development of alternative therapeutic approaches. The CRISPR/Cas system, a newly emerging genome editing tool, holds great promise for genome editing and gene therapy. Several in vitro and/or in vivo studies have demonstrated the effectiveness of HBV-specific clustered regularly interspaced short palindromic repeat (CRISPR)/associated protein 9 (CRISPR/Cas9) systems in cleaving HBV DNA and cccDNA. Although recent advances in CRISPR/Cas technology enhance its prospects for clinical application against HBV infection, in vivo delivery of the CRISPR/Cas9 system at targets sites remains a major challenge that needs to be resolved before its clinical application in gene therapy for CHB. In the present review, we discuss CRISPR/Cas9 delivery tools for targeting HBV infection, with a focus on the development of adeno-associated virus vectors and lipid nanoparticle (LNP)-based CRISPR/Cas ribonucleoprotein (RNP) delivery to treat CHB. In addition, we discuss the importance of delivery tools in the enhancement of the antiviral efficacy of CRISPR/Cas9 against HBV infection.

Dibenzocyclooctyne-Branched Primer Assembled Gene Nanovector and Its Potential Applications in Genome Editing

The CRISPR/Cas9 system has been widely used as an efficient genome editing toolkit for gene therapy. The delivery of vectors encoding the full CRISPR/Cas9 components including Cas9 gene and gRNA expression element into cells is the crucial step to effective genome editing. However, the cargo gene sequence for genome editing is usually large, which reduces the cargo encapsulation efficiency and affects the vector size. To obtain a nanovector with high cargo gene loading capacity and biocompatible size, we report the construction of a gene nanovector from branch-PCR with a dibenzocyclooctyne (DBCO)-branched primer and establish the correlation mapping between gene length and nanovector size. The results show that the size of nanovectors can be tuned according to the gene length. According to the findings, we constructed nanovectors carrying the full CRISPR/Cas9 components in 100-200 nm and validated their application in genome editing. The results show that this kind of nanovector exhibits higher serum stability than plasmids and can reach comparable genome editing efficiency with plasmids. Hence, this type of gene nanovector obtained through branch-PCR can carry large gene cargos and maintain a biocompatible nanoscale size, which we envisage will expand its medical applications in gene therapy.

Strategies for Enhancing the Homology-directed Repair Efficiency of CRISPR-Cas Systems

The CRISPR-Cas nuclease has emerged as a powerful genome-editing tool in recent years. The CRISPR-Cas system induces double-strand breaks that can be repaired via the non-homologous end joining or homology-directed repair (HDR) pathway. Compared to non-homologous end joining, HDR can be used for the treatment of incurable monogenetic diseases. Therefore, remarkable efforts have been dedicated to enhancing the efficacy of HDR. In this review, we summarize the currently used strategies for enhancing the HDR efficiency of CRISPR-Cas systems based on three factors: (1) regulation of the key factors in the DNA repair pathways, (2) modulation of the components in the CRISPR machinery, and (3) alteration of the intracellular environment around double-strand breaks. Representative cases and potential solutions for further improving HDR efficiency are also discussed, facilitating the development of new CRISPR technologies to achieve highly precise genetic manipulation in the future.

Inherent and Composite Hydrogels as Promising Materials to Limit Antimicrobial Resistance

Antibiotic resistance has increased significantly in the recent years, and has become a global problem for human health and the environment. As a result, several technologies for the controlling of health-care associated infections have been developed over the years. Thus, the most recent findings in hydrogel fabrication, particularly antimicrobial hydrogels, could offer valuable solutions for these biomedical challenges. In this review, we discuss the most promising strategies in the development of antimicrobial hydrogels and the application of hydrogels in the treatment of microbial infections. The latest advances in the development of inherently and composite antimicrobial hydrogels will be discussed, as well as hydrogels as carriers of antimicrobials, with a focus on antibiotics, metal nanoparticles, antimicrobial peptides, and biological extracts. The emergence of CRISR-Cas9 technology for removing the antimicrobial resistance has led the necessity of new and performant carriers for delivery of the CRISPR-Cas9 system. Different delivery systems, such as composite hydrogels and many types of nanoparticles, attracted a great deal of attention and will be also discussed in this review.

Nanoparticle-based non-viral CRISPR delivery for enhanced immunotherapy

The CRISPR Cas9 system has received considerable attention due to its simplicity, efficiency, and high precision for gene editing. The development of various therapeutic applications of the CRISPR system is under active research. In particular, its proven effects and promise in immunotherapy are of note. CRISPR/Cas9 components can be transported in various forms, such as plasmid DNA, mRNA of the Cas9 protein with gRNA, or a ribonucleoprotein complex. Even with its proven gene editing superiority, there are limitations in delivering the CRISPR system to target cells. CRISPR systems can be delivered via physical methods, viral vectors, or non-viral carriers. The development of diverse types of nanoparticles that could be used as non-viral carriers could overcome the disadvantages of physical techniques and viral vectors such as low cell viability, induction of immune response, limited loading capacity, and lack of targeting ability. Herein, we review the recent developments in applications of CRISPR system-mediated non-viral carriers in immunotherapy, depending on the targeting cell types, and discuss future research directions.

Reflections on drug resistance to KRASG12C inhibitors and gene silencing/editing tools for targeting mutant KRAS in cancer treatment

KRAS is the most commonly mutated oncogene in human tumors, especially in lung, pancreatic, and colorectal cancers. Small-molecule inhibitors targeting mutant KRAS^G12C demonstrated promising anti-tumor effect in patients with non-small cell lung cancer harboring KRAS^G12C mutation, while the intrinsic and acquired drug resistance occurred frequently and might be inevitable. Unlike the protein-level inhibition approach, gene silencing/editing tools for DNA-level knockout and RNA-level knockdown of mutant KRAS may be advantageous since these approaches directly eliminate the production of mutant KRAS-encoded protein. An in-depth understanding of KRAS biology, drug resistance to KRAS^G12C inhibitors and gene silencing/editing methods applied for anti-KRAS therapy may give new insight into the therapeutic strategy for cancer treatment.

Exploring nano-enabled CRISPR-Cas-powered strategies for efficient diagnostics and treatment of infectious diseases

Biomedical researchers have subsequently been inspired the development of new approaches for precisely changing an organism's genomic DNA in order to investigate customized diagnostics and therapeutics utilizing genetic engineering techniques. Clustered Regulatory Interspaced Short Palindromic Repeats (CRISPR) is one such technique that has emerged as a safe, targeted, and effective pharmaceutical treatment against a wide range of disease-causing organisms, including bacteria, fungi, parasites, and viruses, as well as genetic abnormalities. The recent discovery of very flexible engineered nucleic acid binding proteins has changed the scientific area of genome editing in a revolutionary way. Since current genetic engineering technique relies on viral vectors, issues about immunogenicity, insertional oncogenesis, retention, and targeted delivery remain unanswered. The use of nanotechnology has the potential to improve the safety and efficacy of CRISPR/Cas9 component distribution by employing tailored polymeric nanoparticles. The combination of two (CRISPR/Cas9 and nanotechnology) offers the potential to open new therapeutic paths. Considering the benefits, demand, and constraints, the goal of this research is to acquire more about the biology of CRISPR technology, as well as aspects of selective and effective diagnostics and therapies for infectious illnesses and other metabolic disorders. This review advocated combining nanomedicine (nanomedicine) with a CRISPR/Cas enabled sensing system to perform early-stage diagnostics and selective therapy of specific infectious disorders. Such a Nano-CRISPR-powered nanomedicine and sensing system would allow for successful infectious illness control, even on a personal level. This comprehensive study also discusses the current obstacles and potential of the predicted technology.

SUPPLEMENTARY INFORMATION

The online version contains supplementary material available at 10.1007/s40097-022-00472-7.

Calcium-based nanomaterials and their interrelation with chitosan: optimization for pCRISPR delivery

There have been numerous advancements in the early diagnosis, detection, and treatment of genetic diseases. In this regard, CRISPR technology is promising to treat some types of genetic issues. In this study, the relationship between calcium (due to its considerable physicochemical properties) and chitosan (as a natural linear polysaccharide) was investigated and optimized for pCRISPR delivery. To achieve this, different forms of calcium, such as calcium nanoparticles (CaNPs), calcium phosphate (CaP), a binary blend of calcium and chitosan including CaNPs/Chitosan and CaP/Chitosan, as well as their tertiary blend including CaNPs-CaP/Chitosan, were prepared via both routine and green procedures using Salvia hispanica to reduce toxicity and increase nanoparticle stability (with a yield of 85%). Such materials were also applied to the human embryonic kidney (HEK-293) cell line for pCRISPR delivery. The results were optimized using different characterization techniques demonstrating acceptable binding with DNA (for both CaNPs/Chitosan and CaNPs-CaP/Chitosan) significantly enhancing green fluorescent protein (EGFP) (about 25% for CaP/Chitosan and more than 14% for CaNPs-CaP/Chitosan).

SUPPLEMENTARY INFORMATION

The online version contains supplementary material available at 10.1007/s40097-021-00446-1.

An Outlook on Global Regulatory Landscape for Genome-Edited Crops

The revolutionary technology of CRISPR/Cas systems and their extraordinary potential to address fundamental questions in every field of biological sciences has led to their developers being awarded the 2020 Nobel Prize for Chemistry. In agriculture, CRISPR/Cas systems have accelerated the development of new crop varieties with improved traits-without the need for transgenes. However, the future of this technology depends on a clear and truly global regulatory framework being developed for these crops. Some CRISPR-edited crops are already on the market, and yet countries and regions are still divided over their legal status. CRISPR editing does not require transgenes, making CRISPR crops more socially acceptable than genetically modified crops, but there is vigorous debate over how to regulate these crops and what precautionary measures are required before they appear on the market. This article reviews intended outcomes and risks arising from the site-directed nuclease CRISPR systems used to improve agricultural crop plant genomes. It examines how various CRISPR system components, and potential concerns associated with CRISPR/Cas, may trigger regulatory oversight of CRISPR-edited crops. The article highlights differences and similarities between GMOs and CRISPR-edited crops, and discusses social and ethical concerns. It outlines the regulatory framework for GMO crops, which many countries also apply to CRISPR-edited crops, and the global regulatory landscape for CRISPR-edited crops. The article concludes with future prospects for CRISPR-edited crops and their products.

An Outlook on Global Regulatory Landscape for Genome-Edited Crops

The revolutionary technology of CRISPR/Cas systems and their extraordinary potential to address fundamental questions in every field of biological sciences has led to their developers being awarded the 2020 Nobel Prize for Chemistry. In agriculture, CRISPR/Cas systems have accelerated the development of new crop varieties with improved traits—without the need for transgenes. However, the future of this technology depends on a clear and truly global regulatory framework being developed for these crops. Some CRISPR-edited crops are already on the market, and yet countries and regions are still divided over their legal status. CRISPR editing does not require transgenes, making CRISPR crops more socially acceptable than genetically modified crops, but there is vigorous debate over how to regulate these crops and what precautionary measures are required before they appear on the market. This article reviews intended outcomes and risks arising from the site-directed nuclease CRISPR systems used to improve agricultural crop plant genomes. It examines how various CRISPR system components, and potential concerns associated with CRISPR/Cas, may trigger regulatory oversight of CRISPR-edited crops. The article highlights differences and similarities between GMOs and CRISPR-edited crops, and discusses social and ethical concerns. It outlines the regulatory framework for GMO crops, which many countries also apply to CRISPR-edited crops, and the global regulatory landscape for CRISPR-edited crops. The article concludes with future prospects for CRISPR-edited crops and their products.

An Outlook on Global Regulatory Landscape for Genome-Edited Crops

The revolutionary technology of CRISPR/Cas systems and their extraordinary potential to address fundamental questions in every field of biological sciences has led to their developers being awarded the 2020 Nobel Prize for Chemistry. In agriculture, CRISPR/Cas systems have accelerated the development of new crop varieties with improved traits-without the need for transgenes. However, the future of this technology depends on a clear and truly global regulatory framework being developed for these crops. Some CRISPR-edited crops are already on the market, and yet countries and regions are still divided over their legal status. CRISPR editing does not require transgenes, making CRISPR crops more socially acceptable than genetically modified crops, but there is vigorous debate over how to regulate these crops and what precautionary measures are required before they appear on the market. This article reviews intended outcomes and risks arising from the site-directed nuclease CRISPR systems used to improve agricultural crop plant genomes. It examines how various CRISPR system components, and potential concerns associated with CRISPR/Cas, may trigger regulatory oversight of CRISPR-edited crops. The article highlights differences and similarities between GMOs and CRISPR-edited crops, and discusses social and ethical concerns. It outlines the regulatory framework for GMO crops, which many countries also apply to CRISPR-edited crops, and the global regulatory landscape for CRISPR-edited crops. The article concludes with future prospects for CRISPR-edited crops and their products.

The Application of the CRISPR/Cas9 System in the Treatment of Hepatitis B Liver Cancer

The clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated protein 9 (Cas9) system was originally discovered in prokaryotes and functions as part of the adaptive immune system. The experimental research of many scholars, as well as scientific and technological advancements, has allowed prokaryote-derived CRISPR/Cas genome-editing systems to transform our ability to manipulate, detect, image, and annotate specific DNA and RNA sequences in the living cells of diverse species. Through modern genetic engineering editing technology and high-throughput gene sequencing, we can edit and splice covalently closed circular DNA to silence it, and correct the mutation and deletion of liver cancer genes to achieve precise in situ repair of defective genes and prohibit viral infection or replication. Such manipulations do not destroy the structure of the entire genome and facilitate the cure of diseases. In this review, we discussed the possibility that CRISPR/Cas could be used as a treatment for patients with liver cancer caused by hepatitis B virus infection, and reviewed the challenges incurred by this effective gene-editing technology.

Lactate Consumption via Cascaded Enzymes Combined VEGF siRNA for Synergistic Anti-Proliferation and Anti-Angiogenesis Therapy of Tumors

Lactate, as the most abundant component with concentrations of 4-40 mm in tumors, contributes to the regulation of metabolic pathways, angiogenesis, and immunosuppression, exhibiting remarkable potential in cancer treatment. Therefore, a codelivery strategy that combined the cascaded enzymes Lactate oxidase/Catalase (LOx/CAT) and vascular endothelial growth factor (VEGF) siRNA (siVEGF) to suppress tumor proliferation and angiogenesis synergistically is creatively proposed. In brief, the cationic liposomes (LIP) encapsulated with LOx/CAT and siVEGF via hydrophilic interaction and electrostatic adsorption followed by coating with PEGylated phenylboronic acid (PP) is established (PPL@[LOX+CAT]). Moreover, a simple 3-aminophenylboronic acid (PBA)-shielded strategy via fructose (Fru) is applied to further enhance the targeting efficiency in the tumor site. The obtained co-encapsulated nanoparticles (NPs) can simultaneous intracellular release of LOx/CAT and siVEGF, and the collaborative use of LOx and CAT can promote lactate consumption even under a hypoxic tumor microenvironment (TME) without producing systemic toxicity. The combined application of lactate depletion and VEGF silencing demonstrated the efficient migration suppression of 4T1 cells in vitro and superior antitumor and antimetastatic properties in vivo. This work offers a promising tumor treatment strategy via integrating cascaded enzymes and gene therapy, and explores a promising therapy regimen for 4T1 triple-negative breast cancer.

Perfecting Targeting in CRISPR

CRISPR-based genome editing holds promise for genome engineering and other applications in diverse organisms. Defining and improving the genome-wide and transcriptome-wide specificities of these editing tools are essential for realizing their full potential in basic research and biomedical therapeutics. This review provides an overview of CRISPR-based DNA- and RNA-editing technologies, methods to quantify their specificities, and key solutions to reduce off-target effects for research and improve therapeutic applications. Expected final online publication date for the Annual Review of Genetics, Volume 55 is November 2021. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.

Harnessing lipid nanoparticles for efficient CRISPR delivery

The CRISPR-Cas system has revolutionized the biomedical research field with its simple and flexible genome editing method. In October 2020, Emmanuelle Charpentier and Jennifer A. Doudna were awarded the 2020 Nobel Prize in chemistry in recognition of their outstanding contributions to the discovery of CRISPR-Cas9 genetic scissors, which allow scientists to alter DNA sequences with high precision. Recently, the first phase I clinical trials in cancer patients affirmed the safety and feasibility of ex vivo CRISPR-edited T cells. However, specific and effective CRISPR delivery in vivo remains challenging due to the multiple extracellular and intracellular barriers. Here, we discuss the recent advances in novel lipid nanomaterials for CRISPR delivery and describe relevant examples of potential therapeutics in cancers, genetic disorders, and infectious diseases.

Versatile modification of the CRISPR/Cas9 ribonucleoprotein system to facilitate in vivo application

The development of clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated (Cas) systems has created a tremendous wave that is sweeping the world of genome editing. The ribonucleoprotein (RNP) method has evolved to be the most advantageous form for in vivo application. Modification of the CRISPR/Cas9 RNP method to adapt delivery through a variety of carriers can either directly improve the stability and specificity of the gene-editing tool in vivo or indirectly endow the system with high gene-editing efficiency that induces few off-target mutations through different delivery methods. The exploration of in vivo applications mediated by various delivery methods lays the foundation for genome research and variety improvements, which is especially promising for better in vivo research in the field of translational biomedicine. In this review, we illustrate the modifiable structures of the Cas9 nuclease and single guide RNA (sgRNA), summarize the latest research progress and discuss the feasibility and advantages of various methods. The highlighted results will enhance our knowledge, stimulate extensive research and application of Cas9 and provide alternatives for the development of rational delivery carriers in multiple fields.

One-in-one individual package and delivery of CRISPR/Cas9 ribonucleoprotein using apoferritin

So far, most reported delivery of CRISPR/Cas9 is achieved by internalized or encapsulated multiple ribonucleoprotein units into only one carrier unit, with relatively large size. Here, we report a novel, small-sized, individual package of CRISPR/Cas9, via using tetralysine modified H-chian apoferritin (TL-HFn) as packaging material. In this paper, each CRISPR/Cas9 complex is proved to be successfully installed into one TL-HFn (~26 nm), and delivered into the targeting cell via TfR1-mediated endocytosis. We found that after 6 h of treatment, the CRISPR/Cas9 complex can be tracked within the nuclear of Hela cells for the purpose of gene editing of enhanced green fluorescent protein (EGFP). Moreover, TL-HFn individually packed CRISPR/Cas9 displayed higher genome editing activity compared with that of free CRISPR/Cas9 treated group both in vitro (up to 28.96%) and in vivo. Such satisfied genome editing efficiency could be attributed to the endosomal escape and pH-induced disassembly abilities given by TL-HFn after uptake into cytoplasm, which had been verified in our previous research. In all, those results prompted that TL-HFn possessed more potential for intracellular delivery of CRISPR/Cas9, with potential biocompatibility, stability and delivery efficiency.

Interfacing Biomaterials with Synthetic T Cell Immunity

The clinical success of cancer immunotherapy is providing exciting opportunities for the development of new methods to detect and treat cancer more effectively. A new generation of biomaterials is being developed to interface with molecular and cellular features of immunity and ultimately shape or control anti-tumor responses. Recent advances that are supporting the advancement of engineered T cells are focused here. This class of cancer therapy has the potential to cure disease in subsets of patients, yet there remain challenges such as the need to improve response rates and safety while lowering costs to expand their use. To provide a focused overview, recent strategies in three areas of biomaterials research are highlighted: low-cost cell manufacturing to broaden patient access, noninvasive diagnostics for predictive monitoring of immune responses, and strategies for in vivo control that enhance anti-tumor immunity. These research efforts shed light on some of the challenges associated with T cell immunotherapy and how engineered biomaterials that interface with synthetic immunity are gaining traction to solve these challenges.

Exosome/Liposome-like Nanoparticles: New Carriers for CRISPR Genome Editing in Plants

Rapid developments in the field of plant genome editing using clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated protein (Cas) systems necessitate more detailed consideration of the delivery of the CRISPR system into plants. Successful and safe editing of plant genomes is partly based on efficient delivery of the CRISPR system. Along with the use of plasmids and viral vectors as cargo material for genome editing, non-viral vectors have also been considered for delivery purposes. These non-viral vectors can be made of a variety of materials, including inorganic nanoparticles, carbon nanotubes, liposomes, and protein- and peptide-based nanoparticles, as well as nanoscale polymeric materials. They have a decreased immune response, an advantage over viral vectors, and offer additional flexibility in their design, allowing them to be functionalized and targeted to specific sites in a biological system with low cytotoxicity. This review is dedicated to describing the delivery methods of CRISPR system into plants with emphasis on the use of non-viral vectors.

Recent advances in liposome formulations for breast cancer therapeutics

Among many nanoparticle-based delivery platforms, liposomes have been particularly successful with many formulations passed into clinical applications. They are well-established and effective gene and/or drug delivery systems, widely used in cancer therapy including breast cancer. In this review we discuss liposome design with the targeting feature and triggering functions. We also summarise the recent progress (since 2014) in liposome-based therapeutics for breast cancer including chemotherapy and gene therapy. We finally identify some challenges on the liposome technology development for the future clinical translation.

Active Delivery of CRISPR System Using Targetable or Controllable Nanocarriers

Among programmable nuclease-based genome editing tools, the clustered regularly interspaced short palindromic repeats (CRISPR) system with accuracy and the convenient operation is most promising to be applied in gene therapy. The development of effective delivery carriers for the CRISPR system is the major premise to achieve practical applications. Although many nanocarrier-mediated deliveries have been reported to be safer and cheaper over the physical and viral delivery, the accumulation at disease sites or controllability with the spatial or temporal resolution are still desired on nanocarriers to reduce side effects and off-target from the CRISPR system. Therefore, the targetable and controllable nanocarriers to actively deliver the CRISPR system are summarized. The cell or even organ selective nanocarriers are introduced first, followed by the discussion of nanocarriers controlled by biochemical or physical signals. At last, the potential challenges faced by existing nanocarriers are discussed.

Polymeric Delivery of Therapeutic Nucleic Acids

The advent of genome editing has transformed the therapeutic landscape for several debilitating diseases, and the clinical outlook for gene therapeutics has never been more promising. The therapeutic potential of nucleic acids has been limited by a reliance on engineered viral vectors for delivery. Chemically defined polymers can remediate technological, regulatory, and clinical challenges associated with viral modes of gene delivery. Because of their scalability, versatility, and exquisite tunability, polymers are ideal biomaterial platforms for delivering nucleic acid payloads efficiently while minimizing immune response and cellular toxicity. While polymeric gene delivery has progressed significantly in the past four decades, clinical translation of polymeric vehicles faces several formidable challenges. The aim of our Account is to illustrate diverse concepts in designing polymeric vectors towards meeting therapeutic goals of in vivo and ex vivo gene therapy. Here, we highlight several classes of polymers employed in gene delivery and summarize the recent work on understanding the contributions of chemical and architectural design parameters. We touch upon characterization methods used to visualize and understand events transpiring at the interfaces between polymer, nucleic acids, and the physiological environment. We conclude that interdisciplinary approaches and methodologies motivated by fundamental questions are key to designing high-performing polymeric vehicles for gene therapy.

Bio-multifunctional noncovalent porphyrin functionalized carbon-based nanocomposite

Herein, in a one-pot method, the reduced graphene oxide layers with the assistance of multiwalled carbon nanotubes were decorated to provide a suitable space for the in situ growth of CoNi₂S₄, and the porphyrins were incorporated into the layers as well to increase the sensitivity of the prepared nanostructure. The prepared nanocomposite can establish π-π interactions between the genetic material and on the surface of porphyrin rings. Also, hydrogen bonds between genetic domains and the porphyrin' nitrogen and the surface hydroxyl groups are probable. Furthermore, the potential donor-acceptor relationship between the d⁷ transition metal, cobalt, and the genetic material provides a suitable way to increase the interaction and gene loading , and transfections. The reason for this phenomenon was optimized to increase the EGFP by up to 17.9%. Furthermore, the sensing ability of the nanocomposite towards H₂O₂ was investigated. In this regard, the limit of detection of the H₂O₂ obtained 10 µM. Also, the in situ biosensing ability in the HEK-293 and PC12 cell lines was evaluated by the addition of PMA. The nanocomposite showed the ability to detect the released H₂O₂ after adding the minimum amount of 120 ng/mL of the PMA.

Erratic journey of CRISPR/Cas9 in oncology from bench-work to successful-clinical therapy

CRISPR is a customized molecular scissor, comprising genetic guide made of RNA and an enzyme, Cas9 which snips DNA in simpler, cheaper and more precise way than any other gene editing tools. In recent years CRISPR/Cas has taken the research world by storm being go-to genome editor for potential gene therapy to fix cancer as well as several hereditary disorders. This review explores the literature around the mechanism of Nobel winning CRISPR/Cas9 and its journey from its discovery to various pre-clinical and clinical trials in oncology, focusing mostly on PD-1 knockout CAR-T cell therapy. It also discusses the hurdles and ethical dispute associated with CRISPR, such as unintended on-target and off-target cuts, embryonic germ-line editing. Despite the controversies regarding the safety of this technique, many studies reported promising results on targeting cancer and other diseases using CRISPR/Cas9. Outcomes from the first successful clinical trial showed the beneficial long term effect on genetically modified T-cells in targeting cancer cells which opens the door for CRISPR to be the most preferred technique to help treating cancer and other diseases in future. As far as germ-line editing is concerned, further studies are needed to support the safety of this technique in humans fixing genetic disorders and mutations. Therefore till date only somatic cell editing is ethically approved.

CRISPR genome engineering for retinal diseases

Novel gene therapy treatments for inherited retinal diseases have been at the forefront of translational medicine over the past couple of decades. Since the discovery of CRISPR mechanisms and their potential application for the treatment of inherited human conditions, it seemed inevitable that advances would soon be made using retinal models of disease. The development of CRISPR technology for gene therapy and its increasing potential to selectively target disease-causing nucleotide changes has been rapid. In this chapter, we discuss the currently available CRISPR toolkit and how it has been and can be applied in the future for the treatment of inherited retinal diseases. These blinding conditions have until now had limited opportunity for successful therapeutic intervention, but the discovery of CRISPR has created new hope of achieving such, as we discuss within this chapter.

Rational designs of in vivo CRISPR-Cas delivery systems

The CRISPR-Cas system initiated a revolution in genome editing when it was, for the first time, demonstrated success in the mammalian cells. Today, scientists are able to readily edit genomes, regulate gene transcription, engineer posttranscriptional events, and image nucleic acids using CRISPR-Cas-based tools. However, to efficiently transport CRISPR-Cas into target tissues/cells remains challenging due to many extra- and intra-cellular barriers, therefore largely limiting the applications of CRISPR-based therapeutics in vivo. In this review, we summarize the features of plasmid-, RNA- and ribonucleoprotein (RNP)-based CRISPR-Cas therapeutics. Then, we survey the current in vivo delivery systems. We specify the requirements for efficient in vivo delivery in clinical settings, and highlight both efficiency and safety for different CRISPR-Cas tools.

Efficient Polymer-Mediated Delivery of Gene-Editing Ribonucleoprotein Payloads through Combinatorial Design, Parallelized Experimentation, and Machine Learning

Chemically defined vectors such as cationic polymers are versatile alternatives to engineered viruses for the delivery of genome-editing payloads. However, their clinical translation hinges on rapidly exploring vast chemical design spaces and deriving structure-function relationships governing delivery performance. Here, we discovered a polymer for efficient intracellular ribonucleoprotein (RNP) delivery through combinatorial polymer design and parallelized experimental workflows. A chemically diverse library of 43 statistical copolymers was synthesized via combinatorial RAFT polymerization, realizing systematic variations in physicochemical properties. We selected cationic monomers that varied in their pK_a values (8.1-9.2), steric bulk, and lipophilicity of their alkyl substituents. Co-monomers of varying hydrophilicity were also incorporated, enabling elucidation of the roles of protonation equilibria and hydrophobic-hydrophilic balance in vehicular properties and performance. We screened our multiparametric vector library through image cytometry and rapidly uncovered a hit polymer (P38), which outperforms state-of-the-art commercial transfection reagents, achieving nearly 60% editing efficiency via nonhomologous end-joining. Structure-function correlations underlying editing efficiency, cellular toxicity, and RNP uptake were probed through machine learning approaches to uncover the physicochemical basis of P38's performance. Although cellular toxicity and RNP uptake were solely determined by polyplex size distribution and protonation degree, respectively, these two polyplex design parameters were found to be inconsequential for enhancing editing efficiency. Instead, polymer hydrophobicity and the Hill coefficient, a parameter describing cooperativity-enhanced polymer deprotonation, were identified as the critical determinants of editing efficiency. Combinatorial synthesis and high-throughput characterization methodologies coupled with data science approaches enabled the rapid discovery of a polymeric vehicle that would have otherwise remained inaccessible to chemical intuition. The statistically derived design rules elucidated herein will guide the synthesis and optimization of future polymer libraries tailored for therapeutic applications of RNP-based genome editing.

Nanovesicle-Mediated Delivery Systems for CRISPR/Cas Genome Editing

Genome-editing technology has emerged as a potential tool for treating incurable diseases for which few therapeutic modalities are available. In particular, discovery of the clustered regularly interspaced short palindromic repeats (CRISPR)/Cas system together with the design of single-guide RNAs (sgRNAs) has sparked medical applications of genome editing. Despite the great promise of the CRISPR/Cas system, its clinical application is limited, in large part, by the lack of adequate delivery technology. To overcome this limitation, researchers have investigated various systems, including viral and nonviral vectors, for delivery of CRISPR/Cas and sgRNA into cells. Among nonviral delivery systems that have been studied are nanovesicles based on lipids, polymers, peptides, and extracellular vesicles. These nanovesicles have been designed to increase the delivery of CRISPR/Cas and sgRNA through endosome escape or using various stimuli such as light, pH, and environmental features. This review covers the latest research trends in nonviral, nanovesicle-based delivery systems that are being applied to genome-editing technology and suggests directions for future progress.

Emerging Prospects of Exosomes for Cancer Treatment: From Conventional Therapy to Immunotherapy

Exosomes are a class of extracellular vesicles of around 100 nm in diameter that are secreted by most cells and contain various bioactive molecules reflecting their cellular origin and mediate intercellular communication. Studies of these exosomal features in tumor pathogenesis have led to the development of therapeutic and diagnostic approaches using exosomes for cancer therapy. Exosomes have many advantages for conveying therapeutic agents such as small interfering RNAs, microRNAs, membrane-associated proteins, and chemotherapeutic compounds; thus, they are considered a prime candidate as a delivery tool for cancer treatment. Since exosomes also provide an optimal microenvironment for the effective function of immunomodulatory factors, exosomes harboring bioactive molecules have been bioengineered as cancer immunotherapies that can effectively activate each stage of the cancer immunity cycle to successfully elicit cancer-specific immunity. This review discusses the advantages of exosomes for treating cancer and the challenges that must be overcome for their successful clinical development.

Base editing: advances and therapeutic opportunities

Base editing - the introduction of single-nucleotide variants (SNVs) into DNA or RNA in living cells - is one of the most recent advances in the field of genome editing. As around half of known pathogenic genetic variants are due to SNVs, base editing holds great potential for the treatment of numerous genetic diseases, through either temporary RNA or permanent DNA base alterations. Recent advances in the specificity, efficiency, precision and delivery of DNA and RNA base editors are revealing exciting therapeutic opportunities for these technologies. We expect the correction of single point mutations will be a major focus of future precision medicine.

Spatial and Temporal Control of CRISPR-Cas9-Mediated Gene Editing Delivered via a Light-Triggered Liposome System

The CRISPR-Cas9 and related systems offer a unique genome-editing tool allowing facile and efficient introduction of heritable and locus-specific sequence modifications in the genome. Despite its molecular precision, temporal and spatial control of gene editing with the CRISPR-Cas9 system is very limited. We developed a light-sensitive liposome delivery system that offers a high degree of spatial and temporal control of gene editing with the CRISPR-Cas9 system. We demonstrated its efficient protein release by respectively assessing the targeted knockout of the eGFP gene in human HEK293/GFP cells and the TNFAIP3 gene in TNFα-induced HEK293 cells. We further validated our results at a single-cell resolution using an in vivo eGFP reporter system in zebrafish (77% knockout). These findings indicate that light-triggered liposomes may have new options for precise control of CRISPR-Cas9 release and editing.

CRISPR-Cas systems: Overview, innovations and applications in human disease research and gene therapy

Genome editing is the modification of genomic DNA at a specific target site in a wide variety of cell types and organisms, including insertion, deletion and replacement of DNA, resulting in inactivation of target genes, acquisition of novel genetic traits and correction of pathogenic gene mutations. Due to the advantages of simple design, low cost, high efficiency, good repeatability and short-cycle, CRISPR-Cas systems have become the most widely used genome editing technology in molecular biology laboratories all around the world. In this review, an overview of the CRISPR-Cas systems will be introduced, including the innovations, the applications in human disease research and gene therapy, as well as the challenges and opportunities that will be faced in the practical application of CRISPR-Cas systems.

Electrosprayed Alginate Nanoparticles as CRISPR Plasmid DNA Delivery Carrier: Preparation, Optimization, and Characterization

Therapeutic gene editing is becoming more feasible with the emergence of the Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR)/CRISPR-associated protein (Cas) system. However, the successful implementation of CRISPR/Cas9-based therapeutics requires a safe and efficient in vivo delivery of the CRISPR components, which remains challenging. This study presents successful preparation, optimization, and characterization of alginate nanoparticles (ALG NPs), loaded with two CRISPR plasmids, using electrospray technique. The aim of this delivery system is to edit a target gene in another plasmid (green fluorescent protein (GFP)). The effect of formulation and process variables were evaluated. CRISPR ALG NPs showed mean size and zeta potential of 228 nm and −4.42 mV, respectively. Over 99.0% encapsulation efficiency was achieved while preserving payload integrity. The presence of CRISPR plasmids in the ALG NPs was confirmed by Attenuated Total Reflectance-Fourier Transform Infrared Spectroscopy. The tests revealed that the nanoparticles were cytocompatible and successfully introduced the Cas9 transgene in HepG2 cells. Nanoparticles-transfected HepG2 was able to edit its target plasmid by introducing double-strand break (DSB) in GFP gene, indicating the bioactivity of CRISPR plasmids encapsulated in alginate nanoparticles. This suggests that this method is suitable for biomedical application in vitro or ex vivo. Future investigation of theses nanoparticles might result in nanocarrier suitable for in vivo delivery of CRISPR/Cas9 system.

Functionalized exosome harboring bioactive molecules for cancer therapy

Exosomes are nanosized vesicles with a lipid membrane that are secreted by most cells and play a crucial role as intermediates of intercellular communication because they carry bioactive molecules. Exosomes are promising for drug delivery of chemicals, proteins, and nucleic acids owing to their inherent properties such as excellent biocompatibility, high tumor targetability, and prolonged circulation in vivo. In this review, we cover recent approaches and advances made in the field of exosome-mediated delivery of bioactive molecules for cancer therapy and factors that affect the clinical use of exosomes. This review can be used as a guideline for further study in expanding the utility of therapeutic exosomes.