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2.
Microbiome ; 12(1): 44, 2024 Mar 04.
Article in English | MEDLINE | ID: mdl-38433268

ABSTRACT

BACKGROUND: The severity and frequency of drought are expected to increase substantially in the coming century and dramatically reduce crop yields. Manipulation of rhizosphere microbiomes is an emerging strategy for mitigating drought stress in agroecosystems. However, little is known about the mechanisms underlying how drought-resistant plant recruitment of specific rhizosphere fungi enhances drought adaptation of drought-sensitive wheats. Here, we investigated microbial community assembly features and functional profiles of rhizosphere microbiomes related to drought-resistant and drought-sensitive wheats by amplicon and shotgun metagenome sequencing techniques. We then established evident linkages between root morphology traits and putative keystone taxa based on microbial inoculation experiments. Furthermore, root RNA sequencing and RT-qPCR were employed to explore the mechanisms how rhizosphere microbes modify plant response traits to drought stresses. RESULTS: Our results indicated that host plant signature, plant niche compartment, and planting site jointly contribute to the variation of soil microbiome assembly and functional adaptation, with a relatively greater effect of host plant signature observed for the rhizosphere fungi community. Importantly, drought-resistant wheat (Yunhan 618) possessed more diverse bacterial and fungal taxa than that of the drought-sensitive wheat (Chinese Spring), particularly for specific fungal species. In terms of microbial interkingdom association networks, the drought-resistant variety possessed more complex microbial networks. Metagenomics analyses further suggested that the enriched rhizosphere microbiomes belonging to the drought-resistant cultivar had a higher investment in energy metabolism, particularly in carbon cycling, that shaped their distinctive drought tolerance via the mediation of drought-induced feedback functional pathways. Furthermore, we observed that host plant signature drives the differentiation in the ecological role of the cultivable fungal species Mortierella alpine (M. alpina) and Epicoccum nigrum (E. nigrum). The successful colonization of M. alpina on the root surface enhanced the resistance of wheats in response to drought stresses via activation of drought-responsive genes (e.g., CIPK9 and PP2C30). Notably, we found that lateral roots and root hairs were significantly suppressed by co-colonization of a drought-enriched fungus (M. alpina) and a drought-depleted fungus (E. nigrum). CONCLUSIONS: Collectively, our findings revealed host genotypes profoundly influence rhizosphere microbiome assembly and functional adaptation, as well as it provides evidence that drought-resistant plant recruitment of specific rhizosphere fungi enhances drought tolerance of drought-sensitive wheats. These findings significantly underpin our understanding of the complex feedbacks between plants and microbes during drought, and lay a foundation for steering "beneficial keystone biome" to develop more resilient and productive crops under climate change. Video Abstract.


Subject(s)
Ascomycota , Drought Resistance , Triticum , Rhizosphere , Genotype , Fungi/genetics
4.
Antiviral Res ; 220: 105736, 2023 12.
Article in English | MEDLINE | ID: mdl-37863359

ABSTRACT

Apoptosis signal-regulating kinase 1 (ASK1)/MAP3K5 is a stress response kinase that is activated by various stimuli. It is known as an upstream activator of p38- Mitogen-activated protein kinase (p38MAPK) and c-Jun N-terminal kinase (JNK) that are reactive oxygen species (ROS)-induced kinases. Accumulating evidence show that ROS accumulate in virus-infected cells. Here, we investigated the relationship between viruses and ASK1/p38MAPK or ASK1/JNK pathways. Our findings suggest that virus infection activates ASK1 related pathways. In parallel, ASK1 inhibition led to a remarkable reduction in the replication of a broad range of viruses including severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), vaccinia virus (VV), vesicular stomatitis virus (VSV), Herpes Simplex Virus (HSV), and Human Immunodeficiency virus (HIV) in different human cell lines. Our work demonstrates the potential therapeutic use of Selonsertib, an ASK1 inhibitor, as a pan-antiviral drug in humans. Surprisingly, we observed differential effects of Selonsertib in in vitro and in vivo hamster models, suggesting caution in using rodent models to predict clinical and therapeutic outcomes in humans.


Subject(s)
COVID-19 , Signal Transduction , Humans , RNA, Viral , MAP Kinase Kinase Kinase 5/metabolism , MAP Kinase Kinase Kinase 5/pharmacology , Reactive Oxygen Species , Antiviral Agents/pharmacology , SARS-CoV-2/metabolism , p38 Mitogen-Activated Protein Kinases/metabolism , JNK Mitogen-Activated Protein Kinases/metabolism , Apoptosis
5.
J Med Virol ; 95(10): e29170, 2023 10.
Article in English | MEDLINE | ID: mdl-37822054

ABSTRACT

Immunogenicity of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) bivalent mRNA-1273.214 vaccine (Original/Omicron B.1.1.529 [BA.1]) is underreported in vulnerable older adults in congregate care settings. In residents of 26 long-term care and retirement homes in Ontario, Canada, humoral (i.e., serum anti-spike and anti-receptor binding domain [anti-RBD]) IgG and IgA antibodies and live SARS-CoV-2 neutralization) and cellular (i.e., CD4+ and CD8+ activation-induced marker spike-specific T cell memory) responses were assessed 7-120 days postvaccination with four monovalent mRNA vaccines (n = 494) or subsequent bivalent mRNA-1273.214 vaccination (fifth vaccine) (n = 557). Within 4 months, anti-spike and anti-RBD antibody levels were similar after monovalent and bivalent vaccination in infection-naïve individuals. Hybrid immunity (i.e., vaccination and natural infection) generally increased humoral responses. After bivalent vaccination, compared to monovalent vaccination, residents with hybrid immunity had elevated anti-spike and anti-RBD IgG and IgA antibodies. Omicron BA.1 antibody-mediated neutralization, and CD8+ T cell memory responses to the Omicron BA.1 spike protein, were also higher after bivalent vaccination. Humoral and cellular responses were, therefore, noninferior within 4 months of bivalent mRNA-1273.214 vaccination compared to monovalent mRNA vaccination. Waning of humoral but not cellular immunity was particularly evident in individuals without hybrid immunity. Continued monitoring of vaccine-associated and hybrid immunity against emerging Omicron variants of concern is necessary to assess longevity of protection.


Subject(s)
COVID-19 , Long-Term Care , Humans , Aged , Ontario , Retirement , SARS-CoV-2/genetics , COVID-19/prevention & control , mRNA Vaccines , Vaccination , Cohort Studies , Immunoglobulin A , Immunoglobulin G , Antibodies, Viral , Antibodies, Neutralizing
6.
EClinicalMedicine ; 63: 102148, 2023 Sep.
Article in English | MEDLINE | ID: mdl-37753447

ABSTRACT

Background: Older adults are at increased risk of SARS-CoV-2 Omicron infection and severe disease, especially those in congregate living settings, despite high SARS-CoV-2 vaccine coverage. It is unclear whether hybrid immunity (combined vaccination and infection) after one Omicron infection provides increased protection against subsequent Omicron reinfection in older adults. Methods: Incidence of SARS-CoV-2 Omicron infection was examined in 750 vaccinated residents of long-term care and retirement homes in the observational cohort COVID in Long-Term Care Study in Ontario, Canada, within a 75-day period (July to September 2022). Risk of infection was assessed by Cox proportional hazards regression. Serum anti-spike and anti-RBD SARS-CoV-2 IgG and IgA antibodies, microneutralization titres, and spike-specific T cell memory responses, were examined in a subset of 318 residents within the preceding three months. Findings: 133 of 750 participants (17.7%) had a PCR-confirmed Omicron infection during the observation period. Increased infection risk was associated with prior Omicron infection (at 9-29 days: 47.67 [23.73-95.76]), and this was not attributed to days since fourth vaccination (1.00 [1.00-1.01]) or residence outbreaks (>6 compared to ≤6: 0.95 [0.37-2.41]). Instead, reinfected participants had lower serum neutralizing antibodies to ancestral and Omicron BA.1 SARS-CoV-2, and lower anti-RBD IgG and IgA antibodies, after their initial Omicron infection. Interpretation: Counterintuitively, SARS-CoV-2 Omicron infection was associated with increased risk of Omicron reinfection in residents of long-term care and retirement homes. Less robust humoral hybrid immune responses in older adults may contribute to risk of Omicron reinfection. Funding: COVID-19 Immunity Task Force of the Public Health Agency of Canada.

7.
PLoS Pathog ; 19(6): e1011485, 2023 06.
Article in English | MEDLINE | ID: mdl-37384813

ABSTRACT

Mucosa-associated invariant T (MAIT) cells are MR1-restricted, innate-like T lymphocytes with tremendous antibacterial and immunomodulatory functions. Additionally, MAIT cells sense and respond to viral infections in an MR1-independent fashion. However, whether they can be directly targeted in immunization strategies against viral pathogens is unclear. We addressed this question in multiple wild-type and genetically altered but clinically relevant mouse strains using several vaccine platforms against influenza viruses, poxviruses and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). We demonstrate that 5-(2-oxopropylideneamino)-6-D-ribitylaminouracil (5-OP-RU), a riboflavin-based MR1 ligand of bacterial origin, can synergize with viral vaccines to expand MAIT cells in multiple tissues, reprogram them towards a pro-inflammatory MAIT1 phenotype, license them to bolster virus-specific CD8+ T cell responses, and potentiate heterosubtypic anti-influenza protection. Repeated 5-OP-RU administration did not render MAIT cells anergic, thus allowing for its inclusion in prime-boost immunization protocols. Mechanistically, tissue MAIT cell accumulation was due to their robust proliferation, as opposed to altered migratory behavior, and required viral vaccine replication competency and Toll-like receptor 3 and type I interferon receptor signaling. The observed phenomenon was reproducible in female and male mice, and in both young and old animals. It could also be recapitulated in a human cell culture system in which peripheral blood mononuclear cells were exposed to replicating virions and 5-OP-RU. In conclusion, although viruses and virus-based vaccines are devoid of the riboflavin biosynthesis machinery that supplies MR1 ligands, targeting MR1 enhances the efficacy of vaccine-elicited antiviral immunity. We propose 5-OP-RU as a non-classic but potent and versatile vaccine adjuvant against respiratory viruses.


Subject(s)
COVID-19 , Mucosal-Associated Invariant T Cells , Vaccines , Female , Male , Humans , Mice , Animals , Vaccine Efficacy , Leukocytes, Mononuclear , COVID-19/metabolism , SARS-CoV-2 , Riboflavin/metabolism , Histocompatibility Antigens Class I , Minor Histocompatibility Antigens
8.
Emerg Infect Dis ; 29(7): 1386-1396, 2023 07.
Article in English | MEDLINE | ID: mdl-37308158

ABSTRACT

Isolating and characterizing emerging SARS-CoV-2 variants is key to understanding virus pathogenesis. In this study, we isolated samples of the SARS-CoV-2 R.1 lineage, categorized as a variant under monitoring by the World Health Organization, and evaluated their sensitivity to neutralizing antibodies and type I interferons. We used convalescent serum samples from persons in Canada infected either with ancestral virus (wave 1) or the B.1.1.7 (Alpha) variant of concern (wave 3) for testing neutralization sensitivity. The R.1 isolates were potently neutralized by both the wave 1 and wave 3 convalescent serum samples, unlike the B.1.351 (Beta) variant of concern. Of note, the R.1 variant was significantly more resistant to type I interferons (IFN-α/ß) than was the ancestral isolate. Our study demonstrates that the R.1 variant retained sensitivity to neutralizing antibodies but evolved resistance to type I interferons. This critical driving force will influence the trajectory of the pandemic.


Subject(s)
COVID-19 , Interferon Type I , Humans , SARS-CoV-2/genetics , Interferon Type I/genetics , Antibodies, Neutralizing , COVID-19 Serotherapy , Canada/epidemiology , Antibodies, Viral , Spike Glycoprotein, Coronavirus
9.
PLoS One ; 18(2): e0281673, 2023.
Article in English | MEDLINE | ID: mdl-36791069

ABSTRACT

OBJECTIVES: The dosing interval of a primary vaccination series can significantly impact on vaccine immunogenicity and efficacy. The current study compared 3 dosing intervals for the primary vaccination series of the BNT162b2 mRNA COVID-19 vaccine, on humoral immune response and durability against SARS-CoV-2 ancestral and Beta variants up to 9 months post immunization. METHODS: Three groups of age- and sex-matched healthcare workers (HCW) who received 2 primary doses of BNT162b2 separated by 35-days, 35-42 days or >42-days were enrolled. Vaccine induced antibody titers at 3 weeks, 3 and 6-9 months post-second dose were assessed. RESULTS: There were 309 age- and sex-matched HCW (mean age 43 [sd 13], 58% females) enrolled. Anti-SARS-CoV-2 binding (IgG, IgM, IgA) and neutralizing antibody titers showed significant waning in levels beyond 35 days post first dose. The second dose induced a significant rise in antibody titers, which peaked at 3 weeks and then declined at variable rates across groups. The magnitude, consistency and durability of response was greater for anti-Spike than anti-RBD antibodies; and for IgG than IgA or IgM. Compared to the shorter schedules, a longer interval of >42 days offered the highest binding and neutralizing antibody titers against SARS-CoV-2 ancestral and Beta (B1.351) variants beyond 3 months post-vaccination. CONCLUSIONS: This is the first comprehensive study to compare 3 dosing intervals for the primary vaccination of BNT162b2 mRNA COVID-19 vaccine implemented in the real world. These findings suggest that delaying the second dose beyond 42 days can potentiate and prolong the humoral response against ancestral and Beta variants of SARS-CoV-2 up to 9 months post-vaccination.


Subject(s)
COVID-19 Vaccines , COVID-19 , Female , Humans , Adult , Male , BNT162 Vaccine , Immunity, Humoral , Prospective Studies , COVID-19/prevention & control , SARS-CoV-2/genetics , Health Personnel , RNA, Messenger , Antibodies, Neutralizing , Immunoglobulin A , Immunoglobulin G , Immunoglobulin M , Antibodies, Viral , Vaccination , mRNA Vaccines
10.
Acad Med ; 98(3): 410-419, 2023 03 01.
Article in English | MEDLINE | ID: mdl-36205493

ABSTRACT

PURPOSE: To improve awareness of diversity in MD-PhD program applicants, matriculants, and graduates; facilitators and barriers to matriculation and/or completion among minoritized groups; and the effects of research experience programs on admissions processes aimed to increase representation of minoritized groups in MD-PhD programs. METHOD: The authors conducted a scoping review, searching EMBASE, MEDLINE, PsycINFO, CINAHL, and Web of Science through December 21, 2021, for studies that contained data on the characteristics of MD-PhD learners and initiatives aimed to make the clinician-scientist trainee population more diverse. They excluded studies that had no primary data, were unavailable in English, and were not peer-reviewed. RESULTS: Of 4,369 articles identified, 16 met inclusion criteria. Studies conceptualized diversity inconsistently, including as sex/gender disparities (n = 11), race/ethnicity underrepresentation (n = 9), disability (n = 2), first-generation student (n = 1), visible minority (n = 1), Indigenous population (n = 1), and economic/social disadvantage (n = 1). Potential barriers to entering or continuing in an MD-PhD program among women and underrepresented ethnic minorities included the long program duration and lack of mentorship; potential facilitators included the flexibility of the dual-degree program. Limited data on high school, undergraduate, and postbaccalaureate research experience programs targeting underrepresented minorities suggest that they may help facilitate admission into MD-PhD programs. CONCLUSIONS: The findings of this scoping review suggest that the diversity of MD-PhD students has been conceptualized in unitary, inconsistent terms, without addressing how different dimensions of diversity may intersect and impact MD-PhD admissions. Future studies should be explicit and intentional in defining "diversity" as it relates to their research questions, explore the impact of intersectionality, and systematically identify and address causal facilitators and barriers of entry to and completion of MD-PhD programs among minoritized groups.


Subject(s)
Biomedical Research , Social Group , Humans , Female , Minority Groups , Biomedical Research/education , Students , Ethnicity
11.
Nat Rev Immunol ; 23(6): 381-396, 2023 06.
Article in English | MEDLINE | ID: mdl-36536068

ABSTRACT

Neutralizing antibodies are known to have a crucial role in protecting against SARS-CoV-2 infection and have been suggested to be a useful correlate of protection for vaccine clinical trials and for population-level surveys. In addition to neutralizing virus directly, antibodies can also engage immune effectors through their Fc domains, including Fc receptor-expressing immune cells and complement. The outcome of these interactions depends on a range of factors, including antibody isotype-Fc receptor combinations, Fc receptor-bearing cell types and antibody post-translational modifications. A growing body of evidence has shown roles for these Fc-dependent antibody effector functions in determining the outcome of SARS-CoV-2 infection. However, measuring these functions is more complicated than assays that measure antibody binding and virus neutralization. Here, we examine recent data illuminating the roles of Fc-dependent antibody effector functions in the context of SARS-CoV-2 infection, and we discuss the implications of these data for the development of next-generation SARS-CoV-2 vaccines and therapeutics.


Subject(s)
COVID-19 , Humans , COVID-19 Vaccines , Antibodies, Viral , SARS-CoV-2 , Antibodies, Neutralizing , Immunoglobulin Fc Fragments , Receptors, Fc
12.
J Immunol ; 209(10): 1892-1905, 2022 11 15.
Article in English | MEDLINE | ID: mdl-36426948

ABSTRACT

Chronic infection with human CMV may contribute to poor vaccine efficacy in older adults. We assessed the effects of CMV serostatus on Ab quantity and quality, as well as cellular memory recall responses, after two and three SARS-CoV-2 mRNA vaccine doses, in older adults in assisted living facilities. CMV serostatus did not affect anti-Spike and anti-receptor-binding domain IgG Ab levels, nor neutralization capacity against wild-type or ß variants of SARS-CoV-2 several months after vaccination. CMV seropositivity altered T cell expression of senescence-associated markers and increased effector memory re-expressing CD45RA T cell numbers, as has been previously reported; however, this did not impact Spike-specific CD4+ T cell memory recall responses. CMV-seropositive individuals did not have a higher incidence of COVID-19, although prior infection influenced humoral immunity. Therefore, CMV seropositivity may alter T cell composition but does not impede the durability of humoral protection or cellular memory responses after SARS-CoV-2 mRNA vaccination in older adults.


Subject(s)
COVID-19 , Cytomegalovirus Infections , Humans , Aged , COVID-19 Vaccines , Cytomegalovirus , SARS-CoV-2 , COVID-19/prevention & control , Antibodies , Vaccination , mRNA Vaccines
13.
Cell Rep Med ; 3(8): 100718, 2022 08 16.
Article in English | MEDLINE | ID: mdl-35977467

ABSTRACT

The conserved hemagglutinin stalk domain is an attractive target for broadly effective antibody-based therapeutics and next-generation universal influenza vaccines. Protection provided by hemagglutinin stalk-binding antibodies is principally mediated through activation of immune effector cells. Titers of stalk-binding antibodies are highly variable on an individual level and tend to increase with age as a result of increasing exposures to influenza virus. In our study, we show that stalk-binding antibodies cooperate with neuraminidase inhibitors to protect against influenza virus infection in an Fc-dependent manner. These data suggest that the effectiveness of neuraminidase inhibitors is likely influenced by an individual's titers of stalk-binding antibodies and that neuraminidase inhibitors may enhance the effectiveness of future stalk-binding monoclonal antibody-based treatments.


Subject(s)
Influenza Vaccines , Influenza, Human , Orthomyxoviridae , Antibodies, Viral , Hemagglutinin Glycoproteins, Influenza Virus/chemistry , Hemagglutinins , Humans , Immunoglobulin Fc Fragments/immunology , Influenza, Human/drug therapy , Neuraminidase
14.
Int J Biol Macromol ; 218: 639-653, 2022 Oct 01.
Article in English | MEDLINE | ID: mdl-35872313

ABSTRACT

As a hydrolytic product of collagen, gelatin is a polypeptide of biological origin. Gelatin hydrogels emerge as promising material candidates for traditional dressings due to good biocompatibility and the ability to keep wounds moist. However, it is difficult to simultaneously achieve gelatin hydrogel with robust mechanical property for long-term usage, reliable tissue adhesion, self-healing and antibacterial properties. Herein, we propose a simply synthesized strategy of a multifunctional gelatin hydrogel dressing, which is constructed by conjugating a newly synthesized 2-(4'-aldehydephenyl)-4-(2',3',4'-trihydroxyphenyl)-2,3-phthalazine-1(2H)-one (THPZB) to gelatin with Schiff base and chelating with Fe3+ ions (termed G/THPZB/Fe hydrogel). The twisted structure of phthalazinone in THPZB leads to entanglement of gelatin molecular chains, which resolves the stiffness-toughness conflict of the hydrogel. Furthermore, the strong tissue adhesion and fast self-healing capability mainly originate from the hydrogen bonding of the pyrogallol in THPZB. In vitro study shows that the hydrogels possess good biocompatibility with L929 cells, hemostatic and antibacterial activity. In the rat model of skin infection, the hydrogel dressing not only have no adverse effects on vital organs, but also can effectively promote wound healing of bacterial infection. Considering that it has multiple functions, G/THPZB/Fe hydrogel can be used as a promising wound dressing for biomedical applications.


Subject(s)
Hydrogels , Urochordata , Adhesives/chemistry , Animals , Anti-Bacterial Agents/chemistry , Anti-Bacterial Agents/pharmacology , Bandages , Gelatin/chemistry , Hydrogels/chemistry , Hydrogels/pharmacology , Rats , Tissue Adhesions
15.
Open Forum Infect Dis ; 9(7): ofac205, 2022 Jul.
Article in English | MEDLINE | ID: mdl-35791356

ABSTRACT

Background: Nonpharmaceutical interventions such as physical distancing and mandatory masking were adopted in many jurisdictions during the coronavirus disease 2019 pandemic to decrease spread of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). We determined the effects of these interventions on incidence of healthcare utilization for other infectious diseases. Methods: Using a healthcare administrative dataset, we employed an interrupted time series analysis to measure changes in healthcare visits for various infectious diseases across the province of Ontario, Canada, from January 2017 to December 2020. We used a hierarchical clustering algorithm to group diagnoses that demonstrated similar patterns of change through the pandemic months. Results: We found that visits for infectious diseases commonly caused by communicable respiratory pathogens (eg, acute bronchitis, acute sinusitis) formed distinct clusters from diagnoses that often originate from pathogens derived from the patient's own flora (eg, urinary tract infection, cellulitis). Moreover, infectious diagnoses commonly arising from communicable respiratory pathogens (hierarchical cluster 1: highly impacted diagnoses) were significantly decreased, with a rate ratio (RR) of 0.35 (95% confidence interval [CI], .30-.40; P < .001) after the introduction of public health interventions in April-December 2020, whereas infections typically arising from the patient's own flora (hierarchical cluster 3: minimally impacted diagnoses) did not demonstrate a sustained change in incidence (RR, 0.95 [95% CI, .90-1.01]; P = .085). Conclusions: Public health measures to curtail the incidence of SARS-CoV-2 were widely effective against other communicable respiratory infectious diseases with similar modes of transmission but had little effect on infectious diseases not strongly dependent on person-to-person transmission.

16.
J Inorg Biochem ; 234: 111899, 2022 09.
Article in English | MEDLINE | ID: mdl-35716549

ABSTRACT

Polyoxidometalates (POMs) exhibit a range of biological properties that can be exploited for a variety of therapeutic applications. However, their potential utility as antivirals has been largely overlooked in the ongoing efforts to identify safe, effective and robust therapeutic agents to combat COVID-19. We focus on decavanadate (V10), a paradigmatic member of the POM family, to highlight the utility of electrostatic forces as a means of disrupting molecular processes underlying the SARS-CoV-2 entry into the host cell. While the departure from the traditional lock-and-key approach to the rational drug design relies on less-specific and longer-range interactions, it may enhance the robustness of therapeutic agents by making them less sensitive to the viral mutations. Native mass spectrometry (MS) not only demonstrates the ability of V10 to associate with the receptor-binding domain of the SARS-CoV-2 spike protein, but also provides evidence that this association disrupts the protein binding to its host cell-surface receptor. Furthermore, V10 is also shown to be capable of binding to the polybasic furin cleavage site within the spike protein, which is likely to decrease the effectiveness of the proteolytic processing of the latter (a pre-requisite for the viral fusion with the host cell membrane). Although in vitro studies carried out with SARS-CoV-2 infected cells identify V10 cytotoxicity as a major factor limiting its utility as an antiviral agent, the collected data provide a compelling stimulus for continuing the search for effective, robust and safe therapeutics targeting the novel coronavirus among members of the POM family.


Subject(s)
COVID-19 Drug Treatment , Spike Glycoprotein, Coronavirus , Antiviral Agents/chemistry , Antiviral Agents/pharmacology , Humans , SARS-CoV-2 , Spike Glycoprotein, Coronavirus/chemistry , Spike Glycoprotein, Coronavirus/genetics , Spike Glycoprotein, Coronavirus/metabolism , Static Electricity , Vanadates/pharmacology , Virus Internalization
17.
PLoS Pathog ; 18(5): e1010471, 2022 05.
Article in English | MEDLINE | ID: mdl-35512020

ABSTRACT

The ability to treat severe viral infections is limited by our understanding of the mechanisms behind virus-induced immunopathology. While the role of type I interferons (IFNs) in early control of viral replication is clear, less is known about how IFNs can regulate the development of immunopathology and affect disease outcomes. Here, we report that absence of type I IFN receptor (IFNAR) is associated with extensive immunopathology following mucosal viral infection. This pathology occurred independent of viral load or type II immunity but required the presence of macrophages and IL-6. The depletion of macrophages and inhibition of IL-6 signaling significantly abrogated immunopathology. Tissue destruction was mediated by macrophage-derived matrix metalloproteinases (MMPs), as MMP inhibition by doxycycline and Ro 28-2653 reduced the severity of tissue pathology. Analysis of post-mortem COVID-19 patient lungs also displayed significant upregulation of the expression of MMPs and accumulation of macrophages. Overall, we demonstrate that IFNs inhibit macrophage-mediated MMP production to prevent virus-induced immunopathology and uncover MMPs as a therapeutic target towards viral infections.


Subject(s)
COVID-19 , Interferon Type I , Orthomyxoviridae Infections , Humans , Interleukin-6/metabolism , Macrophages/metabolism , Proteolysis
18.
Mol Cancer Ther ; 21(6): 999-1009, 2022 06 01.
Article in English | MEDLINE | ID: mdl-35405743

ABSTRACT

One obstacle for human solid tumor immunotherapy research is the lack of clinically relevant animal models. In this study, we sought to establish a chimeric antigen receptor (CAR) T-cell treatment model for naturally occurring canine sarcomas as a model for human CAR T-cell therapy. Canine CARs specific for B7-H3 were constructed using a single-chain variable fragment derived from the human B7-H3-specific antibody MGA271, which we confirmed to be cross-reactive with canine B7-H3. After refining activation, transduction, and expansion methods, we confirmed target killing in a tumor spheroid three-dimensional assay. We designed a B7-H3 canine CAR T-cell and achieved consistently high levels of transduction efficacy, expansion, and in vitro tumor killing. Safety of the CAR T cells were confirmed in two purposely bred healthy canine subjects following lymphodepletion by cyclophosphamide and fludarabine. Immune response, clinical parameters, and manifestation were closely monitored after treatments and were shown to resemble that of humans. No severe adverse events were observed. In summary, we demonstrated that similar to human cancers, B7-H3 can serve as a target for canine solid tumors. We successfully generated highly functional canine B7-H3-specific CAR T-cell products using a production protocol that closely models human CAR T-cell production procedure. The treatment regimen that we designed was confirmed to be safe in vivo. Our research provides a promising direction to establish in vitro and in vivo models for immunotherapy for canine and human solid tumor treatment.


Subject(s)
Receptors, Chimeric Antigen , Sarcoma , Animals , B7 Antigens , Cell Line, Tumor , Dogs , Humans , Sarcoma/drug therapy , T-Lymphocytes , Xenograft Model Antitumor Assays
19.
Mol Cancer Ther ; 21(5): 715-726, 2022 05 04.
Article in English | MEDLINE | ID: mdl-35247919

ABSTRACT

Aberrant activity of the H3K27 modifiers EZH2 and BRD4 is an important oncogenic driver for atypical teratoid/rhabdoid tumor (AT/RT), and each is potentially a possible therapeutic target for treating AT/RT. We, therefore, determined whether targeting distinct histone modifier activities was an effective approach for treating AT/RT. The effects of EZH2 and BRD4 inhibition on histone modification, cell proliferation, and cell invasion were analyzed by immunoblotting, MTS assay, colony formation assay, and cell invasion assay. RNA- and chromatin immunoprecipitation-sequencing were used to determine transcriptional and epigenetic changes in AT/RT cells treated with EZH2 and BRD4 inhibitors. We treated mice bearing human AT/RT xenografts with EZH2 and BRD4 inhibitors. Intracranial tumor growth was monitored by bioluminescence imaging, and the therapeutic response was evaluated by animal survival. AT/RT cells showed elevated levels of H3K27 trimethylation (H3K27me3) and H3K27 acetylation (H3K27ac), with expression of EZH2 and BRD4, and lack of SMARCB1 proteins. Targeted inhibition of EZH2 and BRD4 activities reduced cell proliferation and invasiveness of AT/RT in association with decreasing H3K27me3 and H3K27ac. Differential genomic occupancy of H3K27me3 and H3K27ac regulated specific gene expression in response to EZH2 and BRD4 inhibitions. A combination of EZH2 and BRD4 inhibition increased the therapeutic benefit in vitro and in vivo, outperforming either monotherapy. Overall, histones H3K27me3 and H3K27ac were elevated in AT/RT cells and distributed in distinct chromatin regions to regulate specific gene expression and to promote AT/RT growth. Targeting EZH2 and BRD4 activity is, therefore, a potential combination therapy for AT/RT.


Subject(s)
Rhabdoid Tumor , Acetylation , Animals , Cell Cycle Proteins/genetics , Cell Line, Tumor , Child , Enhancer of Zeste Homolog 2 Protein/genetics , Gene Expression Regulation, Neoplastic , Histones , Humans , Mice , Nuclear Proteins/genetics , Rhabdoid Tumor/drug therapy , Rhabdoid Tumor/genetics , Transcription Factors/genetics
20.
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
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