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1.
Cell ; 185(5): 896-915.e19, 2022 03 03.
Article in English | MEDLINE | ID: mdl-35180381

ABSTRACT

The emerging SARS-CoV-2 variants of concern (VOCs) threaten the effectiveness of current COVID-19 vaccines administered intramuscularly and designed to only target the spike protein. There is a pressing need to develop next-generation vaccine strategies for broader and long-lasting protection. Using adenoviral vectors (Ad) of human and chimpanzee origin, we evaluated Ad-vectored trivalent COVID-19 vaccines expressing spike-1, nucleocapsid, and RdRp antigens in murine models. We show that single-dose intranasal immunization, particularly with chimpanzee Ad-vectored vaccine, is superior to intramuscular immunization in induction of the tripartite protective immunity consisting of local and systemic antibody responses, mucosal tissue-resident memory T cells and mucosal trained innate immunity. We further show that intranasal immunization provides protection against both the ancestral SARS-CoV-2 and two VOC, B.1.1.7 and B.1.351. Our findings indicate that respiratory mucosal delivery of Ad-vectored multivalent vaccine represents an effective next-generation COVID-19 vaccine strategy to induce all-around mucosal immunity against current and future VOC.


Subject(s)
COVID-19 Vaccines/administration & dosage , COVID-19/prevention & control , Immunity, Mucosal , Administration, Intranasal , Animals , Antibodies, Viral/blood , Antibodies, Viral/immunology , B-Lymphocytes/immunology , B-Lymphocytes/metabolism , COVID-19/virology , COVID-19 Vaccines/immunology , Cytokines/blood , Genetic Vectors/genetics , Genetic Vectors/immunology , Genetic Vectors/metabolism , Mice , Mice, Inbred BALB C , Mice, Inbred C57BL , Neutralization Tests , Nucleocapsid/genetics , Nucleocapsid/immunology , Nucleocapsid/metabolism , Pan troglodytes , SARS-CoV-2/genetics , SARS-CoV-2/immunology , SARS-CoV-2/isolation & purification , Spike Glycoprotein, Coronavirus/genetics , Spike Glycoprotein, Coronavirus/immunology , Spike Glycoprotein, Coronavirus/metabolism , T-Lymphocytes/immunology , T-Lymphocytes/metabolism
2.
Nat Immunol ; 23(12): 1687-1702, 2022 12.
Article in English | MEDLINE | ID: mdl-36456739

ABSTRACT

Aside from centrally induced trained immunity in the bone marrow (BM) and peripheral blood by parenteral vaccination or infection, evidence indicates that mucosal-resident innate immune memory can develop via a local inflammatory pathway following mucosal exposure. However, whether mucosal-resident innate memory results from integrating distally generated immunological signals following parenteral vaccination/infection is unclear. Here we show that subcutaneous Bacillus Calmette-Guérin (BCG) vaccination can induce memory alveolar macrophages (AMs) and trained immunity in the lung. Although parenteral BCG vaccination trains BM progenitors and circulating monocytes, induction of memory AMs is independent of circulating monocytes. Rather, parenteral BCG vaccination, via mycobacterial dissemination, causes a time-dependent alteration in the intestinal microbiome, barrier function and microbial metabolites, and subsequent changes in circulating and lung metabolites, leading to the induction of memory macrophages and trained immunity in the lung. These data identify an intestinal microbiota-mediated pathway for innate immune memory development at distal mucosal tissues and have implications for the development of next-generation vaccine strategies against respiratory pathogens.


Subject(s)
BCG Vaccine , Macrophages, Alveolar , Trained Immunity , Lung , Vaccination , Immunity, Innate
3.
Cell ; 175(6): 1634-1650.e17, 2018 11 29.
Article in English | MEDLINE | ID: mdl-30433869

ABSTRACT

Innate immune memory is an emerging area of research. However, innate immune memory at major mucosal sites remains poorly understood. Here, we show that respiratory viral infection induces long-lasting memory alveolar macrophages (AMs). Memory AMs are programed to express high MHC II, a defense-ready gene signature, and increased glycolytic metabolism, and produce, upon re-stimulation, neutrophil chemokines. Using a multitude of approaches, we reveal that the priming, but not maintenance, of memory AMs requires the help from effector CD8 T cells. T cells jump-start this process via IFN-γ production. We further find that formation and maintenance of memory AMs are independent of monocytes or bone marrow progenitors. Finally, we demonstrate that memory AMs are poised for robust trained immunity against bacterial infection in the lung via rapid induction of chemokines and neutrophilia. Our study thus establishes a new paradigm of immunological memory formation whereby adaptive T-lymphocytes render innate memory of mucosal-associated macrophages.


Subject(s)
CD8-Positive T-Lymphocytes/immunology , Immunity, Innate , Lung/immunology , Macrophages, Alveolar/immunology , T-Lymphocytes, Helper-Inducer/immunology , Animals , CD8-Positive T-Lymphocytes/cytology , Immunologic Memory , Lung/cytology , Macrophages, Alveolar/cytology , Mice , Mice, Inbred BALB C , Mice, Transgenic , Monocytes/cytology , Monocytes/immunology , Respiratory Mucosa/cytology , Respiratory Mucosa/immunology , T-Lymphocytes, Helper-Inducer/cytology
5.
Phys Rev Lett ; 132(3): 036502, 2024 Jan 19.
Article in English | MEDLINE | ID: mdl-38307085

ABSTRACT

The recently discovered nickelate superconductor La_{3}Ni_{2}O_{7} has a high transition temperature near 80 K under pressure, providing an additional avenue for exploring unconventional superconductivity. Here, with state-of-the-art tensor-network methods, we study a bilayer t-J-J_{⊥} model for La_{3}Ni_{2}O_{7} and find a robust s-wave superconductive (SC) order mediated by interlayer magnetic couplings. Large-scale density matrix renormalization group calculations find algebraic pairing correlations with Luttinger parameter K_{SC}≲1. Infinite projected entangled-pair state method obtains a nonzero SC order directly in the thermodynamic limit, and estimates a strong pairing strength Δ[over ¯]_{z}∼O(0.1). Tangent-space tensor renormalization group simulations elucidate the temperature evolution of SC pairing and further determine a high SC temperature T_{c}^{*}/J∼O(0.1). Because of the intriguing orbital selective behaviors and strong Hund's rule coupling in the compound, t-J-J_{⊥} model has strong interlayer spin exchange (while negligible interlayer hopping), which greatly enhances the SC pairing in the bilayer system. Such a magnetically mediated pairing has also been observed recently in the optical lattice of ultracold atoms. Our accurate and comprehensive tensor-network calculations reveal a robust SC order in the bilayer t-J-J_{⊥} model and shed light on the pairing mechanism of the high-T_{c} nickelate superconductor.

6.
7.
Pestic Biochem Physiol ; 201: 105874, 2024 May.
Article in English | MEDLINE | ID: mdl-38685243

ABSTRACT

In insects, chemosensory proteins (CSPs) play an important role in the perception of the external environment and have been widely used for protein-binding characterization. Riptortus pedestris has received increased attention as a potential cause of soybean staygreen syndrome in recent years. In this study, we found that RpedCSP4 expression in the antennae of adult R. pedestris increased with age, with no significant difference in expression level observed between males and females, as determined through quantitative real-time polymerase chain reaction (qRT-PCR). Subsequently, we investigated the ability of RpedCSP4 to bind various ligands (five aggregated pheromone components and 13 soybean volatiles) using a prokaryotic expression system and fluorescence competitive binding assays. We found that RpedCSP4 binds to three aggregated pheromone components of R. pedestris, namely, ((E)-2-hexenyl (Z)-3-hexenoate (E2Z3), (E)-2-hexenyl (E)-2-hexenoate (E2E2), and (E)-2-hexenyl hexenoate (E2HH)), and that its binding capacities are most stable under acidic condition. Finally, the structure and protein-ligand interactions of RpedCSP4 were further analyzed via homology modeling, molecular docking, and targeted mutagenesis experiments. The L29A mutant exhibited a loss of binding ability to these three aggregated pheromone components. Our results show that the olfactory function of RpedCSP4 provides new insights into the binding mechanism of RpedCSPs to aggregation pheromones and contributes to discover new target candidates that will provide a theoretical basis for future population control of R. pedestris.


Subject(s)
Insect Proteins , Pheromones , Animals , Pheromones/metabolism , Insect Proteins/metabolism , Insect Proteins/genetics , Insect Proteins/chemistry , Male , Female , Protein Binding , Heteroptera/metabolism , Heteroptera/genetics
8.
Immunity ; 40(4): 554-68, 2014 Apr 17.
Article in English | MEDLINE | ID: mdl-24726877

ABSTRACT

Aspirin gained tremendous popularity during the 1918 Spanish Influenza virus pandemic, 50 years prior to the demonstration of their inhibitory action on prostaglandins. Here, we show that during influenza A virus (IAV) infection, prostaglandin E2 (PGE2) was upregulated, which led to the inhibition of type I interferon (IFN) production and apoptosis in macrophages, thereby causing an increase in virus replication. This inhibitory role of PGE2 was not limited to innate immunity, because both antigen presentation and T cell mediated immunity were also suppressed. Targeted PGE2 suppression via genetic ablation of microsomal prostaglandin E-synthase 1 (mPGES-1) or by the pharmacological inhibition of PGE2 receptors EP2 and EP4 substantially improved survival against lethal IAV infection whereas PGE2 administration reversed this phenotype. These data demonstrate that the mPGES-1-PGE2 pathway is targeted by IAV to evade host type I IFN-dependent antiviral immunity. We propose that specific inhibition of PGE2 signaling might serve as a treatment for IAV.


Subject(s)
Dinoprostone/metabolism , Influenza A virus/physiology , Interferon Type I/metabolism , Intramolecular Oxidoreductases/antagonists & inhibitors , Macrophages/drug effects , Orthomyxoviridae Infections/drug therapy , Animals , Antigen Presentation/drug effects , Apoptosis/drug effects , Cells, Cultured , Dinoprostone/immunology , Gene Expression Regulation/drug effects , Immunity/drug effects , Immunity/genetics , Interferon Type I/genetics , Intramolecular Oxidoreductases/genetics , Macrophages/immunology , Macrophages/virology , Mice , Mice, Inbred C57BL , Mice, Knockout , Molecular Targeted Therapy , Orthomyxoviridae Infections/immunology , Prostaglandin-E Synthases , Receptors, Prostaglandin E, EP2 Subtype/antagonists & inhibitors , Receptors, Prostaglandin E, EP4 Subtype/antagonists & inhibitors , T-Lymphocytes/immunology , T-Lymphocytes/virology , Virus Replication/genetics
9.
Pharm Res ; 40(5): 1165-1176, 2023 May.
Article in English | MEDLINE | ID: mdl-36991226

ABSTRACT

PURPOSE: Intratracheal delivery and consistent dosing of dry powder vaccines is especially challenging in mice. To address this issue, device design of positive pressure dosators and actuation parameters were assessed for their impacts on powder flowability and in vivo dry powder delivery. METHODS: A chamber-loading dosator assembled with stainless-steel, polypropylene or polytetrafluoroethylene needle-tips was used to determine optimal actuation parameters. Powder loading methods including tamp-loading, chamber-loading and pipette tip-loading were compared to assess performance of the dosator delivery device in mice. RESULTS: Available dose was highest (45%) with a stainless-steel tip loaded with an optimal mass and syringe air volume, primarily due to the ability of this configuration to dissipate static charge. However, this tip encouraged more agglomeration along its flow path in the presence of humidity and was too rigid for intubation of mice compared to a more flexible polypropylene tip. Using optimized actuation parameters, the polypropylene pipette tip-loading dosator achieved an acceptable in vivo emitted dose of 50% in mice. After administering two doses of a spray dried adenovirus encapsulated in mannitol-dextran, high bioactivity was observed in excised mouse lung tissue three days post-infection. CONCLUSIONS: This proof-of-concept study demonstrates for the first time that intratracheal delivery of a thermally stable, viral-vectored dry powder can achieve equivalent bioactivity to the same powder, reconstituted and delivered intratracheally. This work may guide the design and device selection process for murine intratracheal delivery of dry powder vaccines to help progress this promising area of inhalable therapeutics.


Subject(s)
Biological Products , Animals , Mice , Administration, Inhalation , Powders , Polypropylenes , Steel , Dry Powder Inhalers , Particle Size , Aerosols
10.
Pestic Biochem Physiol ; 194: 105513, 2023 Aug.
Article in English | MEDLINE | ID: mdl-37532328

ABSTRACT

Riptortus pedestris (bean bug), a common soybean pest, has a highly developed olfactory system to find hosts for feeding and oviposition. Chemosensory proteins (CSPs) have been identified in many insect species; however, their functions in R. pedestris remain unknown. In this study, quantitative real time-polymerase chain reaction (qRT-PCR) revealed that the expression of RpedCSP12 in the adult antennae of R. pedestris increased with age. Moreover, a significant difference in the expression levels of RpedCSP12 was observed between male and female antennae at one and three days of age. We also investigated the binding ability of RpedCSP12 to different ligands using a prokaryotic expression system and fluorescence competitive binding assays. We found that RpedCSP12 only bound to one aggregation pheromone, (E)-2-hexenyl (Z)-3-hexenoate, and its binding decreased with increasing pH. Furthermore, homology modelling, molecular docking, and site-directed mutagenesis revealed that the Y27A, L74A, and L85A mutants lost their binding ability to (E)-2-hexenyl (Z)-3-hexenoate. Our findings highlight the olfactory roles of RpedCSP12, providing insights into the mechanism by which RpedCSPs bind to aggregation pheromones. Therefore, our study can be used as a theoretical basis for the population control of R. pedestris in the future.


Subject(s)
Heteroptera , Pheromones , Animals , Female , Molecular Docking Simulation , Heteroptera/genetics , Glycine max
11.
Genomics ; 114(5): 110437, 2022 09.
Article in English | MEDLINE | ID: mdl-35902070

ABSTRACT

Neoneuromus ignobilis is an archaic holometabolous aquatic predatory insect. However, a lack of genomic resources hinders the use of whole genome sequencing to explore their genetic basis and molecular mechanisms for adaptive evolution. Here, we provided a high-contiguity, chromosome-level genome assembly of N. ignobilis using high coverage Nanopore and PacBio reads with the Hi-C technique. The final assembly is 480.67 MB in size, containing 12 telomere-ended pseudochromosomes with only 17 gaps. We compared 42 hexapod species genomes including six independent lineages comprising 11 aquatic insects, and found convergent expansions of long wavelength-sensitive and blue-sensitive opsins, thermal stress response TRP channels, and sulfotransferases in aquatic insects, which may be related to their aquatic adaptation. We also detected strong nonrandom signals of convergent amino acid substitutions in aquatic insects. Collectively, our comparative genomic analysis revealed the evidence of molecular convergences in aquatic insects during both gene family evolution and convergent amino acid substitutions.


Subject(s)
Genome , Insecta , Animals , Insecta/genetics , Opsins/genetics , Phylogeny , Sulfotransferases/genetics
12.
Int J Mol Sci ; 24(2)2023 Jan 06.
Article in English | MEDLINE | ID: mdl-36674636

ABSTRACT

The objective of this study is to observe the effect of high selenium on the antioxidant and immune functions of growing goats based on transcriptome sequencing. Eighteen goats were randomly divided into three groups: (1) the control (CON) group was fed a basal diet, and (2) the treatment 1 group (LS) and treatment 2 group (HS) were fed a basal diet with 2.4 and 4.8 mg/kg selenium-yeast (SY), respectively. The results indicate that HS treatment significantly (p < 0.05) increased the apparent digestibility of either extract and significantly increased (p < 0.05) total antioxidant capacity, whereas it significantly (p < 0.05) decreased plasma aspartate aminotransferase and malondialdehyde relative to the control group. The LS treatment had significantly (p < 0.05) increased glutathione S-transferase and catalase compared to CON. A total of 532 differentially expressed genes (DEGs) between the CON and HS were obtained using transcriptome sequencing. Kyoto Encyclopedia of Genes and Genomes analysis identified upregulated (p < 0.05) DEGs mainly related to vascular smooth muscle contraction, alpha-linolenic acid metabolism, biosynthesis of unsaturated fatty acids, the VEGF signalling pathway, and proteoglycans in cancer; downregulated (p < 0.05) DEGs mainly related to the NOD-like receptor signalling pathway, influenza A, cytokine-cytokine receptor interaction, haematopoietic cell lineage, and African trypanosomiasis. Ontology analyses of the top genes show that the identified DEGs are mainly involved in the regulation of granulocyte macrophage colony-stimulating factor production for biological processes, the external side of the plasma membrane for cellular components, and carbohydrate derivative binding for molecular functions. Seven genes are considered potential candidate genes for regulating antioxidant activity, including selenoprotein W, 1, glutathione peroxidase 1, glutathione S-transferase A1, tumour necrosis factor, tumour necrosis factor superfamily member 10, tumour necrosis factor superfamily member 8, and tumour necrosis factor superfamily member 13b. The experimental observations indicate that dietary supplementation with 4.8 mg/kg SY can enhance antioxidant and immune functions by improving muscle immunity, reducing the concentrations of inflammatory molecules, and modulating antioxidant and inflammatory signalling pathways in growing goats.


Subject(s)
Antioxidants , Selenium , Animals , Antioxidants/metabolism , Selenium/metabolism , Transcriptome , Goats/genetics , Saccharomyces cerevisiae/metabolism , Tumor Necrosis Factors/genetics , Immunity
13.
Int J Nurs Pract ; 29(1): e13098, 2023 Feb.
Article in English | MEDLINE | ID: mdl-35971276

ABSTRACT

BACKGROUND: Ulcer area is a critical parameter in diabetic foot ulcer assessment but existing methods have deficiencies for routine measurement. AIM: We hypothesized that the Image J-based Computer Analysis method has a high level of agreement with the commonly used Maximum Length and Width and the Transparent Dressing-based Square Grid methods and aimed to test the consistency and verify the feasibility of the Image J-based Computer Analysis method in the routine assessment of ulcers. METHODS: Outpatient attendees with diabetic foot ulcers at the Department of Endocrinology of Sun Yat-sen Memorial Hospital were enrolled between October 2020 and October 2021. The three methods sequentially assessed the area of 65 included ulcers. Results were analysed using one-way analysis of variance and Bland-Altman plots to perform consistency analysis. RESULTS: The mean ± standard deviation ulcer area measured using the three methods were 14.79 ± 5.39, 14.35 ± 5.26, and 14.30 ± 5.26 cm2 , respectively. The measurement differences among the three groups or between any two were not statistically significant. Bland-Altman plots showed good consistency between the Image J-based Computer Analysis and the other two methods. CONCLUSION: The Image J-based Computer Analysis method can be interchanged with the other methods to assess ulcer areas. It is freely accessible, accurate and home-operable, thus worth consideration by nurses for routine ulcer area assessment.


Subject(s)
Diabetes Mellitus , Diabetic Foot , Humans , Diabetic Foot/diagnosis
14.
Angew Chem Int Ed Engl ; 62(34): e202305357, 2023 Aug 21.
Article in English | MEDLINE | ID: mdl-37313642

ABSTRACT

Pristine fullerene C60 is an excellent electron transport material for state-of-the-art inverted structure perovskite solar cells (PSCs), but its low solubility leaves thermal evaporation as the only method for depositing it into a high-quality electron transport layer (ETL). To address this problem, we herein introduce a highly soluble bowl-shaped additive, corannulene, to assist in C60 -assembly into a smooth and compact film through the favorable bowl-ball interaction. Our results show that not only corannulene can dramatically enhance the film formability of C60 , it also plays a critical role in forming C60 -corannulene (CC) supramolecular species and in boosting intermolecular electron transport dynamics in the ETL. This strategy has allowed CC devices to deliver high power conversion efficiencies up to 21.69 %, which is the highest value among the PSCs based on the solution-processed-C60 (SP-C60 ) ETL. Moreover, the stability of the CC device is far superior to that of the C60 -only device because corannulene can retard and curb the spontaneous aggregation of C60 . This work establishes the bowl-assisted ball assembly strategy for developing low-cost and efficient SP-C60 ETLs with high promise for fully-SP PSCs.

15.
Educ Inf Technol (Dordr) ; 28(5): 5763-5777, 2023.
Article in English | MEDLINE | ID: mdl-36373051

ABSTRACT

The popularisation of an active lifestyle and sports is a hot topic today. The countries activate the interest of the population in physical culture introducing creative training activities in sports. The research highlights that it is important to develop creative thinking in physical education teachers. Thus, the main research goal is to analyse the influence of interactive technologies used to develop creativity among physical education teachers. The researchers use tablet computers with a video communication function for the experiment. All training sessions were conducted on the Zoom conferencing platform. The training took 6 months. The proposed training included power training, yoga, dance and gymnastics. At every third lesson, three respondents developed and presented their training programme for the rest of the group. Torrens creative thinking test was used to assess the results. The comparison of the training dynamics in men and women (P-value = 0.019 and 0.003, respectively (p ≤ 0.05)) proves the effectiveness of the proposed training techniques. It means that this technique is effective for sports activities and can be introduced in educational institutions. The scholars recommend using it in schools, universities and other educational institutions.

16.
Gut ; 71(2): 238-253, 2022 02.
Article in English | MEDLINE | ID: mdl-34836916

ABSTRACT

OBJECTIVE: Helicobacter pylori infection is mostly a family-based infectious disease. To facilitate its prevention and management, a national consensus meeting was held to review current evidence and propose strategies for population-wide and family-based H. pylori infection control and management to reduce the related disease burden. METHODS: Fifty-seven experts from 41 major universities and institutions in 20 provinces/regions of mainland China were invited to review evidence and modify statements using Delphi process and grading of recommendations assessment, development and evaluation system. The consensus level was defined as ≥80% for agreement on the proposed statements. RESULTS: Experts discussed and modified the original 23 statements on family-based H. pylori infection transmission, control and management, and reached consensus on 16 statements. The final report consists of three parts: (1) H. pylori infection and transmission among family members, (2) prevention and management of H. pylori infection in children and elderly people within households, and (3) strategies for prevention and management of H. pylori infection for family members. In addition to the 'test-and-treat' and 'screen-and-treat' strategies, this consensus also introduced a novel third 'family-based H. pylori infection control and management' strategy to prevent its intrafamilial transmission and development of related diseases. CONCLUSION: H. pylori is transmissible from person to person, and among family members. A family-based H. pylori prevention and eradication strategy would be a suitable approach to prevent its intra-familial transmission and related diseases. The notion and practice would be beneficial not only for Chinese residents but also valuable as a reference for other highly infected areas.


Subject(s)
Family Health , Helicobacter Infections/prevention & control , Helicobacter pylori , Infection Control/organization & administration , Adolescent , Adult , Aged , Child , Child, Preschool , China , Consensus , Delphi Technique , Helicobacter Infections/diagnosis , Helicobacter Infections/transmission , Humans , Infant , Middle Aged , Young Adult
17.
J Am Chem Soc ; 144(30): 13839-13850, 2022 Aug 03.
Article in English | MEDLINE | ID: mdl-35862295

ABSTRACT

Despite their multifaceted advantages, inverted perovskite solar cells (PSCs) still suffer from lower power conversion efficiencies (PCEs) than their regular counterparts, which is largely due to recombination energy losses (Eloss) that arise from the chemical, physical, and energy level mismatches, especially at the interfaces between perovskites and fullerene electron transport layers (ETLs). To address this problem, we herein introduce an aminium iodide derivative of a buckybowl (aminocorannulene) that is molecularly layered at the perovskite-ETL interface. Strikingly, besides passivating the PbI2-rich perovskite surface, the aminocorannulene enforces a vertical dipole and enhances the surface n-type character that is more compatible with the ETL, thus boosting the electron extraction and transport dynamics and suppressing interfacial Eloss. As a result, the champion PSC achieves an excellent PCE of over 22%, which is superior compared to that of the control device (∼20%). Furthermore, the device stability is significantly enhanced, owing to a lock-and-key-like grip on the mobile iodides by the buckybowls and the resultant increase of the interfacial ion-migration barrier. This work highlights the potential of buckybowls for the multifunctional surface engineering of perovskite toward high-performance and stable PSCs.

18.
FASEB J ; 35(3): e21409, 2021 03.
Article in English | MEDLINE | ID: mdl-33577115

ABSTRACT

The COVID-19 pandemic has unfolded to be the most challenging global health crisis in a century. In 11 months since its first emergence, according to WHO, the causative infectious agent SARS-CoV-2 has infected more than 100 million people and claimed more than 2.15 million lives worldwide. Moreover, the world has raced to understand the virus and natural immunity and to develop vaccines. Thus, within a short 11 months a number of highly promising COVID-19 vaccines were developed at an unprecedented speed and are now being deployed via emergency use authorization for immunization. Although a considerable number of review contributions are being published, all of them attempt to capture only a specific aspect of COVID-19 or its therapeutic approaches based on ever-expanding information. Here, we provide a comprehensive overview to conceptually thread together the latest information on global epidemiology and mitigation strategies, clinical features, viral pathogenesis and immune responses, and the current state of vaccine development.


Subject(s)
COVID-19 Vaccines/immunology , COVID-19/immunology , COVID-19/prevention & control , Immunity/immunology , Pandemics/prevention & control , Animals , Humans , Immunization/methods , SARS-CoV-2/immunology
19.
Pharm Res ; 39(9): 2315-2328, 2022 Sep.
Article in English | MEDLINE | ID: mdl-35854077

ABSTRACT

PURPOSE: Thermally stable, spray dried vaccines targeting respiratory diseases are promising candidates for pulmonary delivery, requiring careful excipient formulation to effectively encapsulate and protect labile biologics. This study investigates the impact of dextran mass ratio and molecular weight on activity retention, thermal stability and aerosol behaviour of a labile adenoviral vector (AdHu5) encapsulated within a spray dried mannitol-dextran blend. METHODS: Comparing formulations using 40 kDa or 500 kDa dextran at mass ratios of 1:3 and 3:1 mannitol to dextran, in vitro quantification of activity losses and powder flowability was used to assess suitability for inhalation. RESULTS: Incorporating mannitol in a 1:3 ratio with 500 kDa dextran reduced viral titre processing losses below 0.5 log and displayed strong thermal stability under accelerated aging conditions. Moisture absorption and agglomeration was higher in dextran-rich formulations, but under low humidity the 1:3 ratio with 500 kDa dextran powder had the lowest mass median aerodynamic diameter (4.4 µm) and 84% emitted dose from an intratracheal dosator, indicating strong aerosol performance. CONCLUSIONS: Overall, dextran-rich formulations increased viscosity during drying which slowed self-diffusion and favorably hindered viral partitioning at the particle surface. Reducing mannitol content also minimized AdHu5 exclusion from crystalline regions that can force the vector to air-solid interfaces where deactivation occurs. Although increased dextran molecular weight improved activity retention at the 1:3 ratio, it was less influential than the ratio parameter. Improving encapsulation ultimately allows inhalable vaccines to be prepared at higher potency, requiring less powder mass per inhaled dose and higher delivery efficiency.


Subject(s)
Excipients , Vaccines , Administration, Inhalation , Aerosols/chemistry , Dextrans/chemistry , Dry Powder Inhalers , Excipients/chemistry , Mannitol/chemistry , Particle Size , Powders/chemistry
20.
J Immunol ; 205(10): 2750-2762, 2020 11 15.
Article in English | MEDLINE | ID: mdl-32998983

ABSTRACT

Mycobacterium tuberculosis, the causative agent of pulmonary tuberculosis (TB), is responsible for millions of infections and deaths annually. Decades of TB vaccine development have focused on adaptive T cell immunity, whereas the importance of innate immune contributions toward vaccine efficacy has only recently been recognized. Airway macrophages (AwM) are the predominant host cell during early pulmonary M. tuberculosis infection and, therefore, represent attractive targets for vaccine-mediated immunity. We have demonstrated that respiratory mucosal immunization with a viral-vectored vaccine imprints AwM, conferring enhanced protection against heterologous bacterial challenge. However, it is unknown if innate immune memory also protects against M. tuberculosis In this study, by using a murine model, we detail whether respiratory mucosal TB vaccination profoundly alters the airway innate immune landscape associated with AwM prior to M. tuberculosis exposure and whether such AwM play a critical role in host defense against M. tuberculosis infection. Our study reveals an important role of AwM in innate immune protection in early stages of M. tuberculosis infection in the lung.


Subject(s)
Immunity, Innate , Macrophages, Alveolar/immunology , Mycobacterium tuberculosis/immunology , Tuberculosis Vaccines/administration & dosage , Tuberculosis, Pulmonary/immunology , Administration, Mucosal , Animals , Bronchoalveolar Lavage Fluid/cytology , Bronchoalveolar Lavage Fluid/immunology , Disease Models, Animal , Female , Humans , Mice , Tuberculosis Vaccines/immunology , Tuberculosis, Pulmonary/diagnosis , Tuberculosis, Pulmonary/microbiology , Tuberculosis, Pulmonary/prevention & control , Vaccines, Synthetic/administration & dosage , Vaccines, Synthetic/immunology
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