Expression of Gn protein of severe fever with thrombocytopenia syndrome virus and its immunogenicity / 中国生物制品学杂志

@#Objective To express the Gn protein of severe fever with thrombocytopenia syndrome virus(SFTSV) through adeno-associated virus 9(AAV9) expression system and evaluate its immunogenicity.Methods SFTSV Gn gene was inserted into viral vector pAAV-CMV-FH and the recombinant plasmid was transfected into HEK293T cells to obtain recombinant virus AAV9-Gn.The expression of Gn protein was determined by immunofluorescence and Western blot.Eighteen fernale BALB/c mice were randomly divided into three groups:Mock group(serum-free DMEM),AAV9-GFP group(1 × 10~(11) vg) and AAV9-Gn group(1 × 10~(11) vg),all of which were injected intramuscularly into the right hind limb at a dose of 100 μL per mouse.The body mass,diet,behavior and mental state of mice in each group were monitored continuously for 21 d,and the change rate of body mass was calculated;At 2,4,8 and 16 weeks after immunization,the levels of SFTSV neutralizing antibody in serum of mice in each group were detected by fluorescent reduction neutralization test(FRNT),and the levels of specific IgGl and IgG2a in serum of mice in AAV9-Gn group were detected by ELISA.Results After incubation with specific antibody,Vero cells transfected with AAV9-Gn showed specific green fluorescence under fluorescence microscope,and had specific binding to mouse anti-SFTSV Gn monoclonal antibody,and the specific binding bands were found at a relative molecular mass of about 61 000.The body mass of the three groups showed an increasing trend,there was no significant difference between the three groups(F=0.158—2.621,P> 0.05),and the diet,behavior and mental state were normal.At 2,4,8 and 16 weeks after immunization,the titer of SFTSV neutralizing antibody in serum of mice in AAV9-Gn group was significantly higher than that of Mock group and AAV9-GFP group(H=13.332—14.538,each P <0.001),and the titer peak appeared at 8 weeks;The level of specific IgG1 in serum of mice was significantly higher than that of IgG2a(F=4.373—12.975,each P <0.05) at different time points.Conclusion SFTSV Gn protein can be expressed correctly through AAV9 expression system,and has low toxicity to mice with good immunogenicity,which is expected to be a candidate component of SFTSV vaccine.

A Novel Retrograde AAV Variant for Functional Manipulation of Cortical Projection Neurons in Mice and Monkeys / 神经科学通报·英文版

Retrograde adeno-associated viruses (AAVs) are capable of infecting the axons of projection neurons and serve as a powerful tool for the anatomical and functional characterization of neural networks. However, few retrograde AAV capsids have been shown to offer access to cortical projection neurons across different species and enable the manipulation of neural function in non-human primates (NHPs). Here, we report the development of a novel retrograde AAV capsid, AAV-DJ8R, which efficiently labeled cortical projection neurons after local administration into the striatum of mice and macaques. In addition, intrastriatally injected AAV-DJ8R mediated opsin expression in the mouse motor cortex and induced robust behavioral alterations. Moreover, AAV-DJ8R markedly increased motor cortical neuron firing upon optogenetic light stimulation after viral delivery into the macaque putamen. These data demonstrate the usefulness of AAV-DJ8R as an efficient retrograde tracer for cortical projection neurons in rodents and NHPs and indicate its suitability for use in conducting functional interrogations.

Advances in AAV-CRISPR/Cas9-Mediated Hemophilia A Gene Therapy --Review / 中国实验血液学杂志

Hemophilia A(HA) is an X-linked recessive bleeding disorder caused by mutations in coagulation factor VIII. Nowadays, exogenous coagulation factor replacement therapy is the main treatment. With the continuous development of gene therapy, new research directions have been provided for the treatment of hemophilia A. CRISPR-Cas9 technology was applied to select suitable target sites, and mediate the targeted knock-in and efficient expression of exogenous B-domain-deleted FⅧ variant gene through corresponding vectors for the treatment of hemophilia A.CRISPR-Cas9 technology is an emerging gene editing tool with great efficiency, safety and effectiveness, and has been widely used in hemophilia gene therapy research. This paper reviews the vector selection, construction of therapeutic genes, gene editing technology and selection of expression target sites for hemophilia A gene therapy at this stage.

Three years follow-up report of two diffuse connective tissue disease cases caused by SARS-CoV-2 infection / 中国热带医学

@#Abstract: To report on two patients with Coronavirus Disease 2019 (COVID-19) combined with diffuse connective tissue disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection followed for nearly 3 years, in order to understand the long-term effects on the patients' immune system. Both patients were male, aged 81-82 years, and were hospitalized with fever on January 29, 2020 and February 10, 2020, respectively. Both were diagnosed with COVID-19 after positive SARS-CoV-2 polymerase chain reaction (PCR) tests. After receiving anti-infection treatment, cough suppressants, ex‐pectorants, and symptomatic supportive treatment, their body temperature returned to normal and two consecutive PCR tests were negative for SARS-CoV-2, and they were discharged from hospital. However, due to recurring fevers and varying degrees of rheumatic disease-related symptoms, both patients were readmitted to the hospital, indicating the presence of positive auto‐ antibodies and organ involvement. One patient recovered from COVID-19 with recurrent fever, joint pain, muscle aches and subcutaneous nodules, and was subsequently diagnosed with undifferentiated connective tissue disease. The other patient developed recurrent fever, mouth ulcers and rash after recovery from COVID-19 and was subsequently diagnosed with anti neutro phil cytoplasm antibody (ANCA)-associated vasculitis (AAV). The patient was treated with glucocorticoids and immunosuppres sive drugs and the symptoms resolved rapidly and subsequent laboratory and imaging examinations showed stable condition. However, due to self-termination of medication, their symptoms quickly relapsed, and further treatment with glucocorticoids and immunosuppressive agents resulted in sustained stability of their condition. The erythrocyte sedimentation rate and hyper‐sensitive C-reactive protein remained within normal limits, and lung CT scans showed stable lesions with partial absorption.SARS-CoV-2 infection may have long-term effects on patients' immune systems, leading to abnormal immune responses and diffuse connective tissue disease. This suggests that regular follow-up observation of immune system-related diseases may be necessary for elderly patients with COVID-19.

Application of biological mass spectrometry in quality control of adeno-associated virus carrier preparations / 中国药科大学学报

@#Adeno-associated virus (AAV) is a common viral vector used in gene therapy.Because of its high safety and its ability to target a variety of cells, it has been widely used in preclinical and clinical studies.However, during the design and production, AAV vectors have many key quality attributes that affect their safety and efficacy.The development and application of biological mass spectrometry technology provides a convenient platform for the research on biological macromolecules, especially in the aspects of protein sequence, structure and interaction.For AAV vectors, mass spectrometry can facilitate the determination or characterization of capsid protein ratio, post-translational modification, serotype, and empty capsid ratio, thus assisting in the quality control of AAV vectors.Compared with the existing methods, mass spectrometry has the advantages of smaller amount of sample size, faster and more sensitive analysis, being more suitable for the analysis of complete AAV vectors with higher mass resolution, and can distinguish empty capsids, full capsids and partial capsids.In the future, mass spectrometry technology is expected to play a more important role in the design and production of AAV vectors through the coupling of more efficient protein separation technology with mass spectrometry, the development of new information processing software platforms and new mass spectrometry detection techniques.

Targeting Kindlin-2 in adipocytes increases bone mass through inhibiting FAS/PPARγ/FABP4 signaling in mice

Osteoporosis (OP) is a systemic skeletal disease that primarily affects the elderly population, which greatly increases the risk of fractures. Here we report that Kindlin-2 expression in adipose tissue increases during aging and high-fat diet fed and is accompanied by decreased bone mass. Kindlin-2 specific deletion (K2KO) controlled by Adipoq-Cre mice or adipose tissue-targeting AAV (AAV-Rec2-CasRx-sgK2) significantly increases bone mass. Mechanistically, Kindlin-2 promotes peroxisome proliferator-activated receptor gamma (PPARγ) activation and downstream fatty acid binding protein 4 (FABP4) expression through stabilizing fatty acid synthase (FAS), and increased FABP4 inhibits insulin expression and decreases bone mass. Kindlin-2 inhibition results in accelerated FAS degradation, decreased PPARγ activation and FABP4 expression, and therefore increased insulin expression and bone mass. Interestingly, we find that FABP4 is increased while insulin is decreased in serum of OP patients. Increased FABP4 expression through PPARγ activation by rosiglitazone reverses the high bone mass phenotype of K2KO mice. Inhibition of FAS by C75 phenocopies the high bone mass phenotype of K2KO mice. Collectively, our study establishes a novel Kindlin-2/FAS/PPARγ/FABP4/insulin axis in adipose tissue modulating bone mass and strongly indicates that FAS and Kindlin-2 are new potential targets and C75 or AAV-Rec2-CasRx-sgK2 treatment are potential strategies for OP treatment.

Single-shot AAV-vectored vaccine against SARS-CoV-2 with fast and long-lasting immunity

Due to the insufficient long-term protection and significant efficacy reduction to new variants of current COVID-19 vaccines, the epidemic prevention and control are still challenging. Here, we employ a capsid and antigen structure engineering (CASE) strategy to manufacture an adeno-associated viral serotype 6-based vaccine (S663V-RBD), which expresses trimeric receptor binding domain (RBD) of spike protein fused with a biological adjuvant RS09. Impressively, the engineered S663V-RBD could rapidly induce a satisfactory RBD-specific IgG titer within 2 weeks and maintain the titer for more than 4 months. Compared to the licensed BBIBP-CorV (Sinopharm, China), a single-dose S663V-RBD induced more endurable and robust immune responses in mice and elicited superior neutralizing antibodies against three typical SARS-CoV-2 pseudoviruses including wild type, C.37 (Lambda) and B.1.617.2 (Delta). More interestingly, the intramuscular injection of S663V-RBD could overcome pre-existing immunity against the capsid. Given its effectiveness, the CASE-based S663V-RBD may provide a new solution for the current and next pandemic.

Pulmonary delivery of siRNA against acute lung injury/acute respiratory distress syndrome

The use of small interfering RNAs (siRNAs) has been under investigation for the treatment of several unmet medical needs, including acute lung injury/acute respiratory distress syndrome (ALI/ARDS) wherein siRNA may be implemented to modify the expression of pro-inflammatory cytokines and chemokines at the mRNA level. The properties such as clear anatomy, accessibility, and relatively low enzyme activity make the lung a good target for local siRNA therapy. However, the translation of siRNA is restricted by the inefficient delivery of siRNA therapeutics to the target cells due to the properties of naked siRNA. Thus, this review will focus on the various delivery systems that can be used and the different barriers that need to be surmounted for the development of stable inhalable siRNA formulations for human use before siRNA therapeutics for ALI/ARDS become available in the clinic.

SIRT6 as a key event linking P53 and NRF2 counteracts APAP-induced hepatotoxicity through inhibiting oxidative stress and promoting hepatocyte proliferation

Acetaminophen (APAP) overdose is the leading cause of drug-induced liver injury, and its prognosis depends on the balance between hepatocyte death and regeneration. Sirtuin 6 (SIRT6) has been reported to protect against oxidative stress-associated DNA damage. But whether SIRT6 regulates APAP-induced hepatotoxicity remains unclear. In this study, the protein expression of nuclear and total SIRT6 was up-regulated in mice liver at 6 and 48 h following APAP treatment, respectively.

CRISPR-Cas9: A method for establishing rat models of drug metabolism and pharmacokinetics

The 2020 Nobel Prize in Chemistry recognized CRISPR-Cas9, a super-selective and precise gene editing tool. CRISPR-Cas9 has an obvious advantage in editing multiple genes in the same cell, and presents great potential in disease treatment and animal model construction. In recent years, CRISPR-Cas9 has been used to establish a series of rat models of drug metabolism and pharmacokinetics (DMPK), such as

Single-stranded adeno-associated virus serotype 9 mediated gene expression in astrocyte via intravenous delivery / 上海交通大学学报（医学版）

Objective: To investigate the expression of LacZ gene mediated by intravenous injection of the single-stranded adeno-associated virus serotype 9 (ssAAV9) containing hypoxia-responsive element (HRE) promoter in the cerebral ischemic area, and further identify the types of brain cells that can be transfected by the vector. Methods: A mouse model of permanent left distal middle cerebral artery occlusion (dMCAO) was established. The expression of hypoxia-inducible factor-1 (HIF-1) in cerebral ischemic area was detected at 1 and 5 days after ischemia. The ssAAV vector containing HRE-regulated LacZ gene was packaged into the capsid of AAV9 virus (AAV9-H9LacZ), and AAV9-H9LacZ was injected into mice through jugular vein 1 h after the establishment of dMCAO model. Five days after injection of AAV9-H9LacZ, X-gal staining was used to detect the expression of β-galactosidase (β-gal) encoded by the LacZ gene in the ischemic area and liver tissue. Immunofluorescence double staining was used to detect the expression of β-gal in astrocyte, neurons and vascular endothelial cells. Results: The expression of HIF-1 was increased 1 and 5 days after ischemia. β-gal was mainly expressed in ischemic penumbra of mice injected with AAV9-H9LacZ. There was no positive expression of β-gal in the liver tissue of mice. β-gal was mainly co-expressed with glial fibrillary acidic protein as an astrocyte-specific marker, and a little of β-gal was co-expressed with neuron-specific nuclear protein. Conclusion: After cerebral ischemia, intravenous injection of AAV9-H9LacZ can effectively mediate gene expression in astrocyte in the cerebral ischemia area. HRE can effectively control the expression of the LacZ gene in cerebral ischemia.

Natural products, PGC-1 , and Duchenne muscular dystrophy

Peroxisome proliferator-activated receptor (PPAR) is a transcriptional coactivator that binds to a diverse range of transcription factors. PPAR coactivator 1 (PGC-1) coactivators possess an extensive range of biological effects in different tissues, and play a key part in the regulation of the oxidative metabolism, consequently modulating the production of reactive oxygen species, autophagy, and mitochondrial biogenesis. Owing to these findings, a large body of studies, aiming to establish the role of PGC-1 in the neuromuscular system, has shown that PGC-1 could be a promising target for therapies targeting neuromuscular diseases. Among these, some evidence has shown that various signaling pathways linked to PGC-1 are deregulated in muscular dystrophy, leading to a reduced capacity for mitochondrial oxidative phosphorylation and increased reactive oxygen species (ROS) production. In the light of these results, any intervention aimed at activating PGC-1 could contribute towards ameliorating the progression of muscular dystrophies. PGC-1 is influenced by different patho-physiological/pharmacological stimuli. Natural products have been reported to display modulatory effects on PPAR activation with fewer side effects in comparison to synthetic drugs. Taken together, this review summarizes the current knowledge on Duchenne muscular dystrophy, focusing on the potential effects of natural compounds, acting as regulators of PGC-1.

Some Thinkings on the Structural Design and Packaging System of Raav-Based Gene Therapy Products / 中国药学杂志

OBJECTIVE: To summarize the structural design strategy and safety assessments of rAAV packaging systems. METHODS: Based on the research progress and international review experience of commercial rAAV products, the design strategy and safety assessments of rAAV packaging systems were summarized. The design strategy and safety assessments of rAAV packaging systems were summarized. RESULTS: The scientific evaluation of the pharmaceutical design of rAAV for human should cover multiple aspects, because various types of AAVs differ in tissue selectivity, viral assembly, transgene expression. Meanwhile, the packaging system is diverse, and the production process is complex. CONCLUSION: The considerations referring to the rAAV structure and mechanisms of producing replication-competent AAV are proposed, and we hope to improve the communications between developers and regulators.

Effect of Eylea on recombinant AAV2-VEGF-induced choroidal neovascularization / 中华实验眼科杂志

Objective To evaluate the effect of Eylea (aflibercept) on recombinant adeno-associated virus 2 (AAV2)-vascular endothelial growth factor (VEGF)-induced choroidal neovascularization (CNV).Methods Two normal cynomolgus monkeys were used in this study.Recombinant AAV2-VEGF was delivered by subretinal injection (60 μl/eye,7.0×1011 IU/ml) into both eyes for each cynomolgus monkey.Both eyes of one animal were treated with single intravitreal injection of Eylea (50 μl/eye,40 mg/ml) 3 weeks after AAV2-VEGF injection,and the two eyes of the other animal were untreated.Optical coherence tomography (OCT),electroretinography (ERG),fluorescein angiography (FFA) and ocular photography were conducted.The experiment was approved by the Institutional Animal Care and Use Committee (IACUC) at JOINN Laboratories (Suzhou) (IACUC serial number:ACU15-1112).Results OCT showed that subretinal hyperreflective material,retinal edema,choroid edema and local pigment epithelial detachment were found after injection of recombinant AAV2-VEGF.All of those symptoms were relieved after treated with Eylea,but aggravated after 4 weeks treated with Eylea.FFA showed that the area of fluorescein leakage expanded obviously after 2 weeks treated with AAV2-VEGF,and it was observed at the whole of fundus posterior pole at 5 weeks after injection.After 1 week treated with Eylea,the area of fluorescein leakage decreased obviously,but increased gradually after 4 weeks treated with Eylea.ERG results showed that the amplitude of ERG decreased gradually after injection of recombinant AAV2-VEGF.After intravitreal injection of Eylea,the amplitude of ERG increased gradually,but it decreased again after 4 weeks treated with Eylea.Conclusions Injection of recombinant AAV2-VEGF is capable of inducing CNV and pathological retinal in cynomolgus monkey.Eylea can prevent the development of clinically relevant CNV,but the effect just lasts for a period.

Relationship between polymorphism site rs5744168 of TLR5 and AAV / 实用医学杂志

Objective To investigate the relationship between putative rs5744168 of Toll-like receptors 5 (TLR5)and ANCA associated small vasculitis (AAV) in Guangxi Han nationality. Methods Polymorphism was analyzed by polymerase chain restricted fragments length polymorphism in 120 cases with AAV and 212 controls. Results (1)There were two genotypes of CC and CT in AAV group and control group. The frequencies distribution of CC and CT in 120 AAV patients were 82.50% and 17.50% respectively and the frequencies of allele C and T 91.25% and 8.75%,respectively. In controls,the genotypefrequencies of CC and CT were 88.68% and 11.3%, and frequencies of allele C and T 94.34% and 5.66%, respectively. No significant difference was found in either genotype distribution or allele frequencies between the patients and the controls ( P > 0 . 05 ) . ( 2 ) Significant reductions in the incidence of BUN, uric acid, quantitative test of 24 h urinary protein and erythrocyte sedimentation rate(ESR) were found in CC genotype (P < 0.05). (3) Binary regression model with a logit link function found total cholesterol was related with AAV. Conclusion The susceptibility of AAV in Guangxi Han population has nothing to do with the polymorphism of rs5744168.In AAV patients, polymorphism of rs5744168 may be associated with ESR, BUN, uric acid and quantitative test of 24 h urinary protein levels.

Differential Cellular Tropism of Lentivirus and Adeno-Associated Virus in the Brain of Cynomolgus Monkey

Many researchers are using viruses to deliver genes of interest into the brains of laboratory animals. However, certain target brain cells are not easily infected by viruses. Moreover, the differential tropism of different viruses in monkey brain is not well established. We investigated the cellular tropism of lentivirus and adeno-associated virus (AAV) toward neuron and glia in the brain of cynomolgus monkeys (Macaca fascularis). Lentivirus and AAV were injected into putamen of the monkey brain. One month after injection, monkeys were sacrificed, and then the presence of viral infection by expression of reporter fluorescence proteins was examined. Tissues were sectioned and stained with NeuN and GFAP antibodies for identifying neuronal cells or astrocytes, respectively, and viral reporter GFP-expressing cells were counted. We found that while lentivirus infected mostly astrocytes, AAV infected neurons at a higher rate than astrocytes. Moreover, astrocytes showed reactiveness when cells were infected by virus, likely due to virus-mediated neuroinflammation. The Sholl analysis was done to compare the hypertrophy of infected and uninfected astrocytes by virus. The lentivirus infected astrocytes showed negligible hypertrophy whereas AAV infected astrocytes showed significant changes in morphology, compared to uninfected astrocytes. In the brain of cynomolgus monkey, lentivirus shows tropism for astrocytes over neurons without much reactivity in astrocytes, whereas AAV shows tropism for neurons over glial cells with a significant reactivity in astrocytes. We conclude that AAV is best-suited for gene delivery to neurons, whereas lentivirus is the best choice for gene delivery to astrocytes in the brain of cynomolgus monkeys.

Simple Purification of Adeno-Associated Virus-DJ for Liver-Specific Gene Expression

Recombinant gene expression using adeno-associated viruses (AAVs) has become a valuable tool in animal studies, as they mediate safe expression of transduced genes for several months. The liver is a major organ of metabolism, and liver-specific expression of a gene can be an invaluable tool for metabolic studies. AAV-DJ is a recombinant AAV generated by the gene shuffling of various AAV serotypes and shares characteristics of AAV2 and AAV8. AAV-DJ contains a heparin-binding domain in its capsid, which suggests that a heparin column could be used for the purification of the AAV. Given that AAV-DJ has been only recently available, relatively little is known about the optimal preparation/purification and application of AAV-DJ. Here, we present a simple large-scale preparation method that can generate 3×10(13) viral particles for in vivo experiments and demonstrate liver-specific gene expression via systemic injection in mice.

Adeno-associated virus mediated p53 gene silence in marmosets / 中国比较医学杂志

Objective To decrease the p53 gene expression at cellular and animal levels in marmoset using RNA interference technique.Methods The shRNA interference sequences were designed and inserted into the adeno-associated virus vector plasmid after bioinformatics analysis.The plasmids were transfected into African green monkey kidney cos-7 cells.The suppression of p53 mRNA was detected by real-time PCR, and the changes of p53 protein expression were detected by Western bolt.The adeno-associated virus-8 was injected through the hind leg vein.The changes of p53 protein expression in the liver tissue was detected by Western blot and immunohistochemistry.Results We screened two RNA interference effective arget sequences.The expression of p53 mRNA was suppressed ( 82.7 ±8.1 )% and ( 80.7 ± 7.5)%, respectively (P<0.05), and the expression of p53 protein was decreased (77.3 ±11.5)% and (73.7 ± 10.7)%, respectively (P<0.05).The two marmosets after virus infection showed that there were virus distributions in the liver, testes, and neck detected by in vivo fluorescence imaging.The expression of p53 in the marmoset liver was detected by western blot, immunohistochemistry analysis showing no obvious changes.Conclusions In the present study, the decrease of P53 gene expression at cellular level is achieved, however, the liver P53 protein in the marmoset liver is not significantly changes.Further optimization of the way of infection is needed in the future.

Chronically Elevated Myeloperoxidase Antineutrophil Cytoplasmic Antibody Levels in an Asymptomatic 91-year-old Patient / General Medicine

Myeloperoxidase antineutrophil cytoplasmic antibody (MPO-ANCA) associated glomerulonephritis is commonly diagnosed in elderly patients with acute kidney injury (AKI). Prompt diagnosis and rapid initiation of appropriate therapy are essential to avoid the development of ANCA-associated vasculitis, which can be a life- and organ-threatening disease. We report a rare case of a 91-year-old male with a high MPO-ANCA titer, who took allopurinol, and showed no symptoms for >20 months, following which sudden AKI and severe bronchial asthma necessitated hemodialysis and steroid administration. Chronically elevated ANCA titers should be examined for causes and followed up to limit the risk of subsequent disease development.

A role for adeno-associated viral vectors in gene therapy: [review]

Gene therapy constitutes a therapeutic intervention based on modification of the genetic material of living cells, by correcting genetic defects or overexpressing therapeutic proteins. The success of gene therapy protocols depends on the availability of therapeutically suitable genes, appropriate gene delivery systems and proof of safety and efficacy. Recent advances on the development of gene delivery systems, particularly on viral vectors engineering and improved gene regulatory systems, have led to marked progress in this field. Although the available vector systems can successfully transfer genes into cells, the ideal delivery vehicle has not been found. In this context, adeno-associated virus vectors (AAV) are arising as a promising tool for a wide range of applications, due to a combination of characteristics such as lack of pathogenicity and immunogenicity, wide range of cell tropism and long-term gene expression. Since its isolation, the biological properties of the adeno-associated virus have been increasingly understood, improving our ability to manipulate and use it as a safe and efficient gene therapy vector of wide spectrum. In this work, we review the bases of gene therapy, main types of gene transfer systems and basic properties and use of AAV vectors.