Advances of mRNA vaccines for COVID-19:A new prophylactic revolution begins

The world is in the midst of 2019 coronavirus infection disease(COVID-19)pandemic.As of 30 January 2021,more than 100 million cases and 2.1 million deaths were confirmed according to the data from the World Health Organization(WHO),resulting in a widespread social and economic turmoil.Therefore,researches worldwide are racing to deploy safe and effective COVID-19 vaccines.

Exosome regulation of immune response mechanism:Pros and cons in immunotherapy

Due to its multiple features,including the ability to orchestrate remote communication between different tissues,the exosomes are the extracellular vesicles arousing the highest interest in the scientific community.Their size,established as an average of 30-150 nm,allows them to be easily uptaken by most cells.According to the type of cells-derived exosomes,they may carry specific biomolecular cargoes used to reprogram the cells they are interacting with.In certain circumstances,exosomes stimulate the immune response by facilitating or amplifying the release of foreign antigens-killing cells,inflammatory factors,or antibodies(immune activation).Meanwhile,in other cases,they are efficiently used by malignant elements such as cancer cells to mislead the immune recognition mechanism,carrying and transferring their cancerous cargoes to distant healthy cells,thus contributing to antigenic invasion(immune suppression).Exosome dichotomic patterns upon immune system regulation present broad advantages in immunotherapy.Its perfect comprehension,from its early biogenesis to its specific interaction with recipient cells,will promote a significant enhancement of immunotherapy employing molecular biology,nanomedicine,and nanotechnology.

猴痘病毒mRNA疫苗的研发进展

猴痘病毒(monkeypox virus, MPXV)属于正痘病毒科正痘病毒属,是一种双链DNA病毒. 2022年7月,猴痘病毒的全球流行使得世界卫生组织将其定义为国际关注的突发公共卫生事件(public health emergency of international concern, PHEIC).猴痘病毒与天花病毒具有高度的同源性和较强的传染性,然而目前并没有针对猴痘病毒的疫苗被批准应用. mRNA疫苗技术是一种新型的疫苗形式,其相关修饰技术于2023年荣获诺贝尔生理学或医学奖,相较于传统疫苗其具有更好的免疫保护效果.本文概述了猴痘病毒mRNA疫苗的研发进展并讨论了猴痘mRNA疫苗的潜在挑战和未来发展方向,以期为进一步推动这一研究领域的发展提供参考.

Recent progresses of exosome-liposome fusions in drug delivery

Exosomes are membrane-bound nanoscale extracellular vesicles,which produced by almost all organisms.Due to the excellent biocompatibility,long circulation time as well as low immunogenicity,exosomes as naturally-derived drug delivery carriers have experienced explosive growth over the past decades.However,issues such as insufficient loading efficiency,heterogeneous delivery efficiency,uncontrollable targeting ability,and low production limit their wide application.Recently,the emerging exosome-liposome fusion strategy has become a potential approach to solve such issues.Thus,this review mainly focuses on the currently developed exosome-liposome fusion strategy and their application in drug delivery as well as disease treatment.This review aims to shed light on the advantages of fusion strategy in drug delivery and provides a better understanding for more rational design.The current challenge and future perspective regarding their clinical translation and application will also be discussed.

pH-Responsive polymer boosts cytosolic siRNA release for retinal neovascularization therapy

Small interfering RNA(siRNA)has a promising future in the treatment of ocular diseases due to its high efficiency,specificity,and low toxicity in inhibiting the expression of target genes and proteins.However,due to the unique anatomical structure of the eye and various barriers,delivering nucleic acids to the retina remains a significant challenge.In this study,we rationally design PACD,an A-B-C type non-viral vector copolymer composed of a hydrophilic PEG block(A),a siRNA binding block(B)and a pH-responsive block(C).PACDs can self-assemble into nanosized polymeric micelles that compact siRNAs into polyplexes through simple mixing.By evaluating its pH-responsive activity,gene silencing efficiency in retinal cells,intraocular distribution,and anti-angiogenesis therapy in a mouse model of hypoxia-induced angiogenesis,we demonstrate the efficiency and safety of PACD in delivering siRNA in the retina.We are surprised to discover that,the PACD/siRNA polyplexes exhibit remarkable intracellular endosomal escape efficiency,excellent gene silencing,and inhibit retinal angiogenesis.Our study provides design guidance for developing efficient nonviral ocular nucleic acid delivery systems.

Legumain-triggered aggregable gold nanoparticles for enhanced intratumoral retention

Insufficient intratumoral retention of nanomedicines remains the major challenge for broad implementation in clinical sets.Herein,we proposed a legumain-triggered aggregable gold nanoparticle(GNP)delivery platform(GNPs-A&C).GNPs-A&C could form intratumoral or intracellular aggregates in response to the overexpressed legumain.The aggregates with size increase not only could reduce back-flow from interstitial space to peripheral bloodstream but also could restrict the cellular exocytosis,leading to enhanced intratumoral retention.In vitro studies demonstrated that GNPs-A&C possessed an excellent legumain responsiveness and the increased size was closely relevant with legumain expression.In vivo studies demonstrated GNPs-A&C possessed slower clearance rate and much higher intratumoral retention within legumain-overexpressed tumor compared to non-aggregable NPs,regardless of intravenous or intratumoral injection.More importantly,this delivery platform significantly improved the chemotherapeutic effect of doxorubicin(DOX)towards subcutaneous xenograft C6 tumor.The effectiveness of this stimulus-responsive aggregable delivery system provides a thinking for designing more intelligent size-tunable nanomedicine that can substantially improve intratumoral retention.

An MPXV mRNA-LNP vaccine candidate elicits protective immune responses against monkeypox virus

The monkeypox virus(MPXV)outbreak,declared a Public Health Emergency of International Concern(PHEIC)by the World Health Organization(WHO)in 2022,continues to pose a significant threat due to the absence of vaccines or drugs for MPXV infection.In this study,we developed an mRNA vaccine that expressing the A29L antigen,a specific protein of the intracellular mature virus.Our vaccine utilizes a thermostable ionizable lipid nanoparticle(iLNP)platform and has been administered to mice.Our find-ings demonstrate that the MPXV A29L mRNA vaccine candidate induces robust cross-neutralizing immune responses against both vaccinia virus(VACV)and MPXV live virus.Furthermore,immunization with the vaccine candidate provided protection against the VACV challenge in mice.These findings underscore the potential of mRNA-LNP vaccines as safe and effective candidates against monkeypox epidemics.Given the current absence of specific interventions for MPXV infection,our study represents a significant step forward in developing a viable solution to combat this ongoing public health threat.

Aptamers targeting SARS-CoV-2 nucleocapsid protein exhibit potential ant1ip1 an-coronavirus activity

Emerging and recurrent infectious diseases caused by human coronaviruses(HCoVs)continue to pose a significant threat to global public health security.In light of this ongoing threat,the development of a broad-spectrum drug to combat HCoVs is an urgently priority.Herein,we report a series of anti-pan-coronavirus ssDNA aptamers screened using Systematic Evolution of Ligands by Exponential Enrichment(SELEX).These aptamers have nanomolar affinity with the nucleocapsid protein(NP)of Severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)and also show excellent binding efficiency to the N proteins of both SARS,MERS,HCoV-OC43 and-NL63 with affinity KD values of 1.31 to 135.36 nM.Such aptamer-based therapeutics exhibited potent antiviral activity against both the authentic SARS-CoV-2 prototype strain and the Omicron variant(BA.5)with EC50 values at 2.00 nM and 41.08 nM,respectively.The protein docking analysis also evidenced that these aptamers exhibit strong affinities for N proteins of pan-coronavirus and other HCoVs(−229E and-HKU1).In conclusion,we have identified six aptamers with a high pan-coronavirus antiviral activity,which could potentially serve as an effective strategy for preventing infections by unknown coronaviruses and addressing the ongoing global health threat.

Advances of nanoparticles as drug delivery systems for disease diagnosis and treatment

Decades have passed since the first nanoparticles-base medicine was approved for human cancer treatment, and the research and development of nanoparticles for drug delivery are always undergoing.Nowadays, the significant advances complicate nanoparticles’ branches, including liposomes, solid lipid nanoparticles, inorganic nanoparticles, micelles, nanovaccines and nano-antibodies, etc. These nanoparticles show numerous capabilities in treatment and diagnosis of stubborn diseases like cancer and neurodegenerative diseases, emerging as novel drug carriers or therapeutic agents in future. In this review, the complicated branches of nanoparticles are classified and summarized, with their property and functions concluded. Besides, there are also some delivery strategies that make nanoparticles smarter and more efficient in drug delivery, and frontiers in these strategies are also summarized in this review. Except these excellent works in newly-produced drug delivery nanoparticles, some points of view and future expectations are made in the end.

Therapeutic siRNA:state of the art

RNA interference(RNAi)is an ancient biological mechanism used to defend against external invasion.It theoretically can silence any disease-related genes in a sequence-specific manner,making small interfering RNA(siRNA)a promising therapeutic modality.After a two-decade journey from its discovery,two approvals of siRNA therapeutics,ONPATTRO®(patisiran)and GIVLAARI™(givosiran),have been achieved by Alnylam Pharmaceuticals.Reviewing the long-term pharmaceutical history of human beings,siRNA therapy currently has set up an extraordinary milestone,as it has already changed and will continue to change the treatment and management of human diseases.It can be administered quarterly,even twice-yearly,to achieve therapeutic effects,which is not the case for small molecules and antibodies.The drug development process was extremely hard,aiming to surmount complex obstacles,such as how to efficiently and safely deliver siRNAs to desired tissues and cells and how to enhance the performance of siRNAs with respect to their activity,stability,specificity and potential off-target effects.In this review,the evolution of siRNA chemical modifications and their biomedical performance are comprehensively reviewed.All clinically explored and commercialized siRNA delivery platforms,including the GalNAc(N-acetylgalactosamine)–siRNA conjugate,and their fundamental design principles are thoroughly discussed.The latest progress in siRNA therapeutic development is also summarized.This review provides a comprehensive view and roadmap for general readers working in the field.

Efficient hepatic delivery and protein expression enabled by optimized mRNA and ionizable lipid nanoparticle

mRNA is a novel class of therapeutic modality that holds great promise in vaccination,protein replacement therapy,cancer immunotherapy,immune cell engineering etc.However,optimization of mRNA molecules and efficient in vivo delivery are quite important but challenging for its broad application.Here we present an ionizable lipid nanoparticle(iLNP)based on iBL0713 lipid for in vitro and in vivo expression of desired proteins using codon-optimized mRNAs.mRNAs encoding luciferase or erythropoietin(EPO)were prepared by in vitro transcription and formulated with proposed iLNP,to form iLP171/mRNA formulations.It was revealed that both luciferase and EPO proteins were successfully expressed by human hepatocellular carcinoma cells and hepatocytes.The maximum amount of protein expression was found at 6 h post-administration.The expression efficiency of EPO with codon-optimized mRNA was significantly higher than that of unoptimized mRNA.Moreover,no toxicity or immunogenicity was observed for these mRNA formulations.Therefore,our study provides a useful and promising platform for mRNA therapeutic development.

Ionizable lipid-assisted efficient hepatic delivery of gene editing elements for oncotherapy

CRISPR/Cas9-based gene editing has emerged as a powerful biotechnological tool,that relies on Cas9 protein and single guided RNA(sgRNA)to edit target DNA.However,the lack of safe and efficient delivery carrier is one of the crucial factors restricting its clinical transformation.Here,we report an ionizable lipid nanoparticle(iLP181,pKa=6.43)based on iLY1809 lipid enabling robust gene editing in vitro and in vivo.The iLP181 effectively encapsulate psgPLK1,the best-performing plasmid expressing for both Cas9 protein and sgRNA targeting Polo-like kinase 1(PLK1).The iLP181/psgPLK1 nanoformulation showed uniformity in size,regular nanostructure and nearly neutral zeta potential at pH 7.4.The nanoformulation effectively triggered editing of PLK1 gene with more than 30%efficiency in HepG2-Luc cells.iLP181/psgPLK1 significantly accumulated in the tumor for more than 5 days after a single intravenous injection.In addition,it also achieved excellent tumor growth suppression compared to other nucleic acid modalities such as siRNA,without inducing adverse effects to the main organs including the liver and kidneys.This study not only provides a clinically-applicable lipid nanocarrier for delivering CRISPR/Cas system(even other bioactive molecules),but also constitutes a potential cancer treatment regimen base on DNA editing of oncogenes.

Antitumor synergism between PAK4 silencing and immunogenic phototherapy of engineered extracellular vesicles

Immunotherapy has revolutionized the landscape of cancer treatment.However,single immunotherapy only works well in a small subset of patients.Combined immunotherapy with antitumor synergism holds considerable potential to boost the therapeutic outcome.Nevertheless,the synergistic,additive or antagonistic antitumor effects of combined immunotherapies have been rarely explored.Herein,we established a novel combined cancer treatment modality by synergizing p21-activated kinase 4(PAK4)silencing with immunogenic phototherapy in engineered extracellular vesicles(EVs)that were fabricated by coating M1 macrophage-derived EVs on the surface of the nano-complex cores assembled with si RNA against PAK4 and a photoactivatable polyethyleneimine.The engineered EVs induced potent PAK4 silencing and robust immunogenic phototherapy,thus contributing to effective antitumor effects in vitro and in vivo.Moreover,the antitumor synergism of the combined treatment was quantitatively determined by the Compu Syn method.The combination index(CI)and isobologram results confirmed that there was an antitumor synergism for the combined treatment.Furthermore,the dose reduction index(DRI)showed favorable dose reduction,revealing lower toxicity and higher biocompatibility of the engineered EVs.Collectively,the study presents a synergistically potentiated cancer treatment modality by combining PAK4 silencing with immunogenic phototherapy in engineered EVs,which is promising for boosting the therapeutic outcome of cancer immunotherapy.

siRNA-functionalized lanthanide nanoparticle enables efficient endosomal escape and cancer treatment

Attaching DNA/RNA to nanomaterials is the basis for nucleic acid-based assembly and drug delivery.Herein,we report that small interfering RNA(siRNA)effectively coordinates with ligand-free lanthanide nanoparticles(NaGdF4 NPs),and forms siRNA/NaGdF4 spherical nucleic acids(SNA).The coordination is primarily attributed to the interaction between Gd and phosphate backbone of the siRNA.Surprisingly,an efficient encapsulation and rapid endosomal escape of siRNA from the endosome/lysosome were achieved,due to its flexible ability to bound to phospholipid head of endosomal membrane,thereby disrupting the membrane structure.Resorting to the dual properties of NaGdF4 NPs,siRNA loading,and endosomal escape,siRNA targeting programmed cell death-ligand 1(siPD-L1)/NaGdF4 SNA triggers significant gene silencing in vitro and in vivo,and effectively represses the tumor growth in both CT26 tumor model and 4T1 orthotopic murine model.

Shear-responsive peptide/siRNA complexes as lung-targeting gene vectors

Particles administrated intravenously will pass through the pulmonary capillary network before being distributed to the body.Therefore,fabrication of vectors sensitive to blood shear and active with blood components should be a practical approach to develop lung-targe ting gene carriers self-regulated by circulatory system.In this work,we designed a series of cationic peptides with the same charge density but varying hydrophobicity and capacity to form hydrogen bonds,and investigated their ability to form co mplexes with siRNA,the behaviours of peptide/siRNA complexes in the presence of serum under shear,and the lung-targeting efficacy of the complexes regulated by blood.The hydrophobic interaction co ntrols the complexation between peptide and siRNA,while the hydrogen bonds are responsible for the binding of peptides to the serum components in blood.In vivo tests show that all the peptide/siRNA complexes can accumulate in lung.However,only the complexes that exhibit weak interaction with serum components and can be broken down by shear avoid the inflammation and death caused by pulmonary embolism.Moreover,the peptide with strong hydrophobicity can retain siRNA in lung without early release of the cargo.Our study provides a step toward the development of adaptive gene carriers under the regulation of circulatory system.

Biosafety materials:Ushering in a new era of infectious disease diagnosis and treatment with the CRISPR/Cas system

Despite multiple virus outbreaks over the past decade,including the devastating coronavirus disease 2019(COVID-19)pandemic,the lack of accurate and timely diagnosis and treatment technologies has wreaked havoc on global biosecurity.The clustered regularly interspaced short palindromic repeats(CRISPR)/CRISPR-associated proteins(Cas)system has the potential to address these critical needs for tackling infectious diseases to detect viral nucleic acids and inhibit viral replication.This review summarizes how the CRISPR/Cas system is being utilized for the treatment and diagnosis of infectious diseases with the help of biosafety materials and highlights the design principle and in vivo and in vitro efficacy of advanced biosafety materials used to deal with virus attacks.

Recent advances in photothermal and RNA interfering synergistic therapy

As a new treatment technique,photothermal therapy(PTT)has aroused worldwide attention in cancer treatment,mainly due to its excellent absorption ability,easy regulation,and biodegradability.Photothermal conversion materials with enhanced permeability and retention effect can be targeted easily to tumor tissue.They can accumulate efficiently to tumor tissues and allow normal tissues and organs not to be affected by temperature,thus significantly helping to reduce the systemic toxicity and improve the antitumor effect.However,PTT alo ne often suffers from the rapeutic resistance and reduced therapeutic efficacy,due to photothermal nanomaterial-mediated fundamental cellular defense mechanism of heat shock response,which could be inhibited by small interfering RNA(siRNA).Nevertheless,photothermal conversion materials as an excellent siRNA delivery carrier may conside rably enhance the delivery efficiency of siRNA.Therefore,photothermal and RNA interfering(RNAi)synergistic therapy has recently aroused extensive attention in tumor treatment.In this review,we mainly summarize the recent advances of photothermal and RNAi synergistic therapy,including some synergistic therapeutic nanoplatforms of inorganic and organic photothermal materials and other combined therapies such as combining with small molecular antitumor agents or PDT/imaging.The combination of various treatment techniques may considerably improve the synergistic therapeutic effect of PTT and RNAi in the treatment of cancers.

Ionizable liposomal siRNA therapeutics enables potent and persistent treatment of Hepatitis B

Small interfering RNA(siRNA)constitutes a promising therapeutic modality supporting the potential functional cure of hepatitis B.A novel ionizable lipidoid nanoparticle(RBP131)and a state-of-the-art lyophilization technology were developed in this study,enabling to deliver siRNA targeting apolipoprotein B(APOB)into the hepatocytes with an ED_(50)of 0.05 mg/kg after intravenous injection.In addition,according to the requirements of Investigational New Drug(IND)application,a potent siRNA targeting hepatitis B virus(HBV)was selected and encapsulated with RBP131 to fabricate a therapeutic formulation termed RB-HBV008.

Identification of SARS-CoV-2-against aptamer with high neutralization activity by blocking the RBD domain of spike protein 1

Dear Editor,The ongoing outbreak of coronavirus disease 2019(COVID-19)caused by severe acute respiratory syndrome coronavirus-2(SARS-CoV-2)poses a great threat to the public health of people and the normal economic and social development around the world.As of January 8,2021,more than 88 million people were infected with SARS-CoV-2,resulting in more than 1.9 million death.

mRNA-based modalities for infectious disease management

The novel coronavirus disease 2019(COVID-19)is still rampant all over the world,causing incalculable losses to the world.Major pharmaceutical organizations around the globe are focusing on vaccine research and drug development to prevent further damage caused by the pandemic.The messenger RNA(mRNA)technology has got ample of attention after the success of the two very effective mRNA vaccines during the recent pandemic of COVID-19.mRNA vaccine has been promoted to the core stage of pharmaceutical industry,and the rapid development of mRNA technology has exceeded expectations.Beyond COVID-19,the mRNA vaccine has been tested for various infectious diseases and undergoing clinical trials.Due to the ability of constant mutation,the viral infections demand abrupt responses and immediate production,and therefore mRNA-based technology offers best answers to sudden outbreaks.The need for mRNA-based vaccine became more obvious due to the recent emergence of new Omicron variant.In this review,we summarized the unique properties of mRNA-based vaccines for infectious diseases,delivery technologies,discussed current challenges,and highlighted the prospects of this promising technology in the future.We also discussed various clinical studies as well preclinical studies conducted on mRNA therapeutics for diverse infectious diseases.