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1.
J Nat Prod ; 87(4): 1003-1012, 2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38579352

RESUMO

Three new (1-3) and six known rotenoids (5-10), along with three known isoflavones (11-13), were isolated from the leaves of Millettia oblata ssp. teitensis. A new glycosylated isoflavone (4), four known isoflavones (14-18), and one known chalcone (19) were isolated from the root wood extract of the same plant. The structures were elucidated by NMR and mass spectrometric analyses. The absolute configuration of the chiral compounds was established by a comparison of experimental ECD and VCD data with those calculated for the possible stereoisomers. This is the first report on the use of VCD to assign the absolute configuration of rotenoids. The crude leaves and root wood extracts displayed anti-RSV (human respiratory syncytial virus) activity with IC50 values of 0.7 and 3.4 µg/mL, respectively. Compounds 6, 8, 10, 11, and 14 showed anti-RSV activity with IC50 values of 0.4-10 µM, while compound 3 exhibited anti-HRV-2 (human rhinovirus 2) activity with an IC50 of 4.2 µM. Most of the compounds showed low cytotoxicity for laryngeal carcinoma (HEp-2) cells; however compounds 3, 11, and 14 exhibited low cytotoxicity also in primary lung fibroblasts. This is the first report on rotenoids showing antiviral activity against RSV and HRV viruses.


Assuntos
Antivirais , Isoflavonas , Millettia , Isoflavonas/farmacologia , Isoflavonas/química , Isoflavonas/isolamento & purificação , Antivirais/farmacologia , Antivirais/química , Antivirais/isolamento & purificação , Millettia/química , Estrutura Molecular , Humanos , Rotenona/farmacologia , Rotenona/química , Rotenona/análogos & derivados , Folhas de Planta/química , Raízes de Plantas/química , Vírus Sincicial Respiratório Humano/efeitos dos fármacos , Vírus Sinciciais Respiratórios/efeitos dos fármacos
2.
Antimicrob Agents Chemother ; 68(3): e0106423, 2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38349161

RESUMO

Screening a library of 1,200 preselected kinase inhibitors for anti-human rhinovirus 2 (HRV-2) activity in HeLa cells identified a class of epidermal growth factor receptor-tyrosine kinase inhibitors (EGFR-TKI) as effective virus blockers. These were based on the 4-anilinoquinazoline-7-oxypiperidine scaffold, with the most potent representative AZ5385 inhibiting the virus with EC50 of 0.35 µM. Several structurally related analogs confirmed activity in the low µM range, while interestingly, other TKIs targeting EGFR lacked anti-HRV-2 activity. To further probe this lack of association between antiviral activity and EGFR inhibition, we stained infected cells with antibodies specific for activated EGFR (Y1068) and did not observe a dependency on EGFR-TK activity. Instead, consecutive passages of HRV-2 in HeLa cells in the presence of a compound and subsequent nucleotide sequence analysis of resistant viral variants identified the S181T and T210A alterations in the major capsid VP1 protein, with both residues located in the vicinity of a known hydrophobic pocket on the viral capsid. Further characterization of the antiviral effects of AZ5385 showed a modest virus-inactivating (virucidal) activity, while anti-HRV-2 activity was still evident when the inhibitor was added as late as 10 h post infection. The RNA copy/infectivity ratio of HRV-2 propagated in AZ5385 presence was substantially higher than that of control HRV indicating that the compound preferentially targeted HRV progeny virions during their maturation in infected cells. Besides HRV, the compound showed anti-respiratory syncytial virus activity, which warrants its further studies as a candidate compound against viral respiratory infections.


Assuntos
Rhinovirus , Humanos , Rhinovirus/química , Rhinovirus/genética , Células HeLa , Proteínas do Capsídeo , Antivirais/química , Receptores ErbB
3.
J Neurol Neurosurg Psychiatry ; 95(4): 325-332, 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-37802637

RESUMO

BACKGROUND: Multiple sclerosis (MS) and presymptomatic axonal injury appear to develop only after an Epstein-Barr virus (EBV) infection. This association remains to be confirmed across a broad preclinical time range, for lytic and latent EBV seroreactivity, and for potential cross-reacting antigens. METHODS: We performed a case-control study with 669 individual serum samples obtained before clinical MS onset, identified through cross-linkage with the Swedish MS register. We assayed antibodies against EBV nuclear antigen 1 (EBNA1), viral capsid antigen p18, glycoprotein 350 (gp350), the potential cross-reacting protein anoctamin 2 (ANO2) and the level of sNfL, a marker of axonal injury. RESULTS: EBNA1 (latency) seroreactivity increased in the pre-MS group, at 15-20 years before clinical MS onset, followed by gp350 (lytic) seroreactivity (p=0.001-0.009), ANO2 seropositivity appeared shortly after EBNA1-seropositivity in 16.7% of pre-MS cases and 10.0% of controls (p=0.001).With an average lag of almost a decade after EBV, sNfL gradually increased, mainly in the increasing subgroup of seropositive pre-MS cases (p=8.10-5 compared with non-MS controls). Seropositive pre-MS cases reached higher sNfL levels than seronegative pre-MS (p=0.038). In the EBNA1-seropositive pre-MS group, ANO2 seropositive cases had 26% higher sNfL level (p=0.0026). CONCLUSIONS: Seroreactivity against latent and lytic EBV antigens, and in a subset ANO2, was detectable on average a decade before the appearance of a gradually increasing axonal injury occurring in the last decade before the onset of clinical MS. These findings strengthen the hypothesis of latent EBV involvement in the pathogenesis of MS.


Assuntos
Infecções por Vírus Epstein-Barr , Esclerose Múltipla , Humanos , Herpesvirus Humano 4 , Estudos de Casos e Controles , Antígenos Virais , Antígenos Nucleares do Vírus Epstein-Barr/metabolismo
4.
Brain ; 147(1): 177-185, 2024 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-37930324

RESUMO

Recent research indicates that multiple sclerosis is preceded by a prodromal phase with elevated levels of serum neurofilament light chain (sNfL), a marker of axonal injury. The effect of environmental risk factors on the extent of axonal injury during this prodrome is unknown. Human herpesvirus 6A (HHV-6A) is associated with an increased risk of developing multiple sclerosis. The objective of this study was to determine if HHV-6A serostatus is associated with the level of sNfL in the multiple sclerosis prodrome, which would support a causative role of HHV-6A. A nested case-control study was performed by crosslinking multiple sclerosis registries with Swedish biobanks. Individuals with biobank samples collected before the clinical onset of multiple sclerosis were included as cases. Controls without multiple sclerosis were randomly selected, matched for biobank, sex, sampling date and age. Serostatus of HHV-6A and Epstein-Barr virus was analysed with a bead-based multiplex assay. The concentration of sNfL was analysed with single molecule array technology. The association between HHV-6A serology and sNfL was assessed by stratified t-tests and linear regressions, adjusted for Epstein-Barr virus serostatus and sampling age. Within-pair ratios of HHV-6A seroreactivity and sNfL were calculated for each case and its matched control. To assess the temporal relationship between HHV-6A antibodies and sNfL, these ratios were plotted against the time to the clinical onset of multiple sclerosis and compared using locally estimated scatterplot smoothing regressions with 95% confidence intervals (CI). Samples from 519 matched case-control pairs were included. In cases, seropositivity of HHV-6A was significantly associated with the level of sNfL (+11%, 95% CI 0.2-24%, P = 0.045) and most pronounced in the younger half of the cases (+24%, 95% CI 6-45%, P = 0.007). No such associations were observed among the controls. Increasing seroreactivity against HHV-6A was detectable before the rise of sNfL (significant within-pair ratios from 13.6 years versus 6.6 years before the clinical onset of multiple sclerosis). In this study, we describe the association between HHV-6A antibodies and the degree of axonal injury in the multiple sclerosis prodrome. The findings indicate that elevated HHV-6A antibodies both precede and are associated with a higher degree of axonal injury, supporting the hypothesis that HHV-6A infection may contribute to multiple sclerosis development in a proportion of cases.


Assuntos
Infecções por Vírus Epstein-Barr , Herpesvirus Humano 6 , Esclerose Múltipla , Humanos , Anticorpos , Biomarcadores , Estudos de Casos e Controles , Herpesvirus Humano 4 , Masculino , Feminino
5.
Nat Commun ; 14(1): 7000, 2023 11 02.
Artigo em Inglês | MEDLINE | ID: mdl-37919266

RESUMO

Viral and host glycans represent an understudied aspect of host-pathogen interactions, despite potential implications for treatment of viral infections. This is due to lack of easily accessible tools for analyzing glycan function in a meaningful context. Here we generate a glycoengineered keratinocyte library delineating human glycosylation pathways to uncover roles of specific glycans at different stages of herpes simplex virus type 1 (HSV-1) infectious cycle. We show the importance of cellular glycosaminoglycans and glycosphingolipids for HSV-1 attachment, N-glycans for entry and spread, and O-glycans for propagation. While altered virion surface structures have minimal effects on the early interactions with wild type cells, mutation of specific O-glycosylation sites affects glycoprotein surface expression and function. In conclusion, the data demonstrates the importance of specific glycans in a clinically relevant human model of HSV-1 infection and highlights the utility of genetic engineering to elucidate the roles of specific viral and cellular carbohydrate structures.


Assuntos
Herpes Simples , Herpesvirus Humano 1 , Humanos , Herpesvirus Humano 1/genética , Herpes Simples/genética , Glicoproteínas/metabolismo , Queratinócitos/metabolismo , Polissacarídeos/metabolismo , Proteínas do Envelope Viral/metabolismo
6.
Scand J Work Environ Health ; 49(6): 386-394, 2023 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-37417898

RESUMO

OBJECTIVE: This study aimed to investigate whether workplace factors and occupations are associated with SARS-CoV-2 infection or severe COVID-19 in the later waves of the pandemic. METHODS: We studied 552 562 cases with a positive test for SARS-CoV-2 in the Swedish registry of communicable diseases, and 5985 cases with severe COVID-19 based on hospital admissions from October 2020 to December 2021. Four population controls were assigned the index dates of their corresponding cases. We linked job histories to job-exposure matrices to assess the odds for different transmission dimensions and different occupations. We used adjusted conditional logistic analyses to estimate odds ratios (OR) for severe COVID-19 and SARS-CoV-2 with 95% confidence intervals (CI). RESULTS: The highest OR for severe COVID-19 were for: regular contact with infected patients, (OR 1.37, 95% CI 1.23-1.54), close physical proximity (OR 1.47, 95% CI 1.34-1.61), and high exposure to diseases or infections (OR 1.72, 95% CI 1.52-1.96). Mostly working outside had lower OR (OR 0.77, 95% CI 0.57-1.06). The odds for SARS-CoV-2 when mostly working outside were similar (OR 0.83, 95% CI 0.80-0.86). The occupation with the highest OR for severe COVID-19 (compared with low-exposure occupations) was certified specialist physician (OR 2.05, 95% CI 1.31-3.21) among women and bus and tram drivers (OR 2.04, 95% CI 1.49-2.79) among men. CONCLUSIONS: Contact with infected patients, close proximity and crowded workplaces increase the risks for severe COVID-19 and SARS-CoV-2 infection. Outdoor work is associated with decreased odds for SARS-CoV-2 infection and severe COVID-19.


Assuntos
COVID-19 , Masculino , Humanos , Feminino , COVID-19/epidemiologia , SARS-CoV-2 , Estudos de Casos e Controles , Suécia/epidemiologia , Fatores de Risco
7.
Annu Rev Virol ; 10(1): 283-304, 2023 09 29.
Artigo em Inglês | MEDLINE | ID: mdl-37285578

RESUMO

N- and O-glycans are both important constituents of viral envelope glycoproteins. O-linked glycosylation can be initiated by any of 20 different human polypeptide O-acetylgalactosaminyl transferases, resulting in an important functional O-glycan heterogeneity. O-glycans are organized as solitary glycans or in clusters of multiple glycans forming mucin-like domains. They are functional both in the viral life cycle and in viral colonization of their host. Negatively charged O-glycans are crucial for the interactions between glycosaminoglycan-binding viruses and their host. A novel mechanism, based on controlled electrostatic repulsion, explains how such viruses solve the conflict between optimized viral attachment to target cells and efficient egress of progeny virus. Conserved solitary O-glycans appear important for viral uptake in target cells by contributing to viral envelope fusion. Dual roles of viral O-glycans in the host B cell immune response, either epitope blocking or epitope promoting, may be exploitable for vaccine development. Finally, specific virus-induced O-glycans may be involved in viremic spread.


Assuntos
Polissacarídeos , Proteínas do Envelope Viral , Humanos , Proteínas do Envelope Viral/metabolismo , Polissacarídeos/metabolismo , Glicosilação , Ligação Viral , Epitopos/metabolismo
8.
Transplant Cell Ther ; 29(4): 275.e1-275.e5, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36720458

RESUMO

Revaccination against tetanus and diphtheria after allogeneic hematopoietic stem cell transplantation (HCT) is usually effective, but the duration of the immunity is unknown. We conducted this study to evaluate humoral immunity to tetanus and diphtheria in long-term survivors and to provide knowledge regarding the need for boosters. The median time from HCT to blood sampling was 14 years (range, 8 to 40 years). All patients had received at least 3 doses of vaccines against both tetanus and diphtheria, either monovalent or combination vaccines containing a full dose of the diphtheria toxoid component. In addition, 1 or more booster doses were administered to 21 of the 146 patients (14%). On enzyme-linked immunosorbent assay, levels <.1 IU/mL for diphtheria and <.01 IU/mL for tetanus were considered low or seronegative. Values between .01 and .5 IU/mL for tetanus and between .1 and 1.0 IU/mL for diphtheria were considered to represent partial protection, and levels >.5 and >1.0 IU/mL were considered high and protective, respectively. In all, 39% of patients were seronegative against diphtheria, 52% had some protection, and 9% had a high titer. In contrast, no patient had become seronegative to tetanus, 32% had "partial protection" against tetanus and 68% had a high titer. In multivariate analysis, active graft-versus-host-disease, sex, or time from sampling did not affect the probability of becoming seronegative or seropositive. Younger age was associated with lower antibody levels to tetanus toxoid, but age was not correlated with antibody levels against diphtheria toxoid. Tetanus immunity was maintained after vaccination in most long-term survivors, but immunity against diphtheria was poor, and boosters should be considered.


Assuntos
Difteria , Transplante de Células-Tronco Hematopoéticas , Tétano , Humanos , Difteria/prevenção & controle , Tétano/prevenção & controle , Anticorpos Antibacterianos , Toxoide Tetânico , Vacinação , Toxoide Diftérico , Corynebacterium
9.
Viruses ; 14(8)2022 08 21.
Artigo em Inglês | MEDLINE | ID: mdl-36016458

RESUMO

The diffusion of viruses at the cell membrane is essential to reach a suitable entry site and initiate subsequent internalization. Although many viruses take advantage of glycosaminoglycans (GAG) to bind to the cell surface, little is known about the dynamics of the virus-GAG interactions. Here, single-particle tracking of the initial interaction of individual herpes simplex virus 1 (HSV-1) virions reveals a heterogeneous diffusive behavior, regulated by cell-surface GAGs with two main diffusion types: confined and normal free. This study reports that different GAGs can have competing influences in mediating diffusion on the cells used here: chondroitin sulfate (CS) enhances free diffusion but hinders virus attachment to cell surfaces, while heparan sulfate (HS) promotes virus confinement and increases entry efficiency. In addition, the role that the viral mucin-like domains (MLD) of the HSV-1 glycoprotein C plays in facilitating the diffusion of the virus and accelerating virus penetration into cells is demonstrated. Together, our results shed new light on the mechanisms of GAG-regulated virus diffusion at the cell surface for optimal internalization. These findings may be extendable to other GAG-binding viruses.


Assuntos
Herpesvirus Humano 1 , Sulfatos de Condroitina/metabolismo , Glicosaminoglicanos/metabolismo , Heparitina Sulfato/metabolismo , Herpesvirus Humano 1/metabolismo , Mucinas/metabolismo , Proteínas do Envelope Viral/metabolismo
10.
ACS Cent Sci ; 8(5): 527-545, 2022 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-35647275

RESUMO

Heparan sulfate (HS) is a cell surface polysaccharide recently identified as a coreceptor with the ACE2 protein for the S1 spike protein on SARS-CoV-2 virus, providing a tractable new therapeutic target. Clinically used heparins demonstrate an inhibitory activity but have an anticoagulant activity and are supply-limited, necessitating alternative solutions. Here, we show that synthetic HS mimetic pixatimod (PG545), a cancer drug candidate, binds and destabilizes the SARS-CoV-2 spike protein receptor binding domain and directly inhibits its binding to ACE2, consistent with molecular modeling identification of multiple molecular contacts and overlapping pixatimod and ACE2 binding sites. Assays with multiple clinical isolates of SARS-CoV-2 virus show that pixatimod potently inhibits the infection of monkey Vero E6 cells and physiologically relevant human bronchial epithelial cells at safe therapeutic concentrations. Pixatimod also retained broad potency against variants of concern (VOC) including B.1.1.7 (Alpha), B.1.351 (Beta), B.1.617.2 (Delta), and B.1.1.529 (Omicron). Furthermore, in a K18-hACE2 mouse model, pixatimod significantly reduced SARS-CoV-2 viral titers in the upper respiratory tract and virus-induced weight loss. This demonstration of potent anti-SARS-CoV-2 activity tolerant to emerging mutations establishes proof-of-concept for targeting the HS-Spike protein-ACE2 axis with synthetic HS mimetics and provides a strong rationale for clinical investigation of pixatimod as a potential multimodal therapeutic for COVID-19.

11.
Clin Ophthalmol ; 16: 959-962, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35386612

RESUMO

Purpose: To assess herpesvirus DNA detection in aqueous humor from a cohort of asymptomatic Scandinavian patients undergoing elective cataract surgery. Patients and Methods: Prospective case series. Aqueous samples were obtained from 30 patients undergoing elective cataract surgery. Polymerase chain reaction (PCR) analysis for herpes simplex virus 1 (HSV1), herpes simplex virus 2 (HSV2), cytomegalovirus (CMV), Epstein Barr virus (EBV) was performed. Toxoplasma was added to the analysis due to its role as pathogen with ocular latency. Results: Mean age of participants was 75.3 years. Sixteen subjects (53%) had ocular comorbidities. Five subjects (17%) had endothelial dysfunction without known hereditary pattern. None of the samples were positive for herpesviruses or toxoplasma. Conclusion: None of the aqueous samples were positive, suggesting shedding does not frequently occur in the aqueous humor of asymptomatic patients.

12.
Blood Adv ; 6(9): 2723-2730, 2022 05 10.
Artigo em Inglês | MEDLINE | ID: mdl-35286374

RESUMO

Recipients of allogeneic hematopoietic stem cell transplantation (allo-HSCT) for hematological diseases are at risk of severe disease and death from COVID-19. To determine the safety and immunogenicity of BNT162b2 and mRNA-1273 COVID-19 vaccines, samples from 50 infection-naive allo-HSCT recipients (median, 92 months from transplantation, range, 7-340 months) and 39 healthy controls were analyzed for serum immunoglobulin G (IgG) against the receptor binding domain (RBD) within spike 1 (S1) of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2; anti-RBD-S1 IgG) and for SARS-CoV-2-specific T-cell immunity, reflected by induction of T-cell-derived interferon-γ in whole blood stimulated ex vivo with 15-mer SI-spanning peptides with 11 amino acid overlap S1-spanning peptides. The rate of seroconversion was not significantly lower in allo-transplanted patients than in controls with 24% (12/50) and 6% (3/50) of patients remaining seronegative after the first and second vaccination, respectively. However, 58% of transplanted patients lacked T-cell responses against S1 peptides after 1 vaccination compared with 19% of controls (odds ratio [OR] 0.17; P = .009, Fisher's exact test) with a similar trend after the second vaccination where 28% of patients were devoid of detectable specific T-cell immunity, compared with 6% of controls (OR 0.18; P = .02, Fisher's exact test). Importantly, lack of T-cell reactivity to S1 peptides after vaccination heralded substandard levels (<100 BAU/mL) of anti-RBD-S1 IgG 5 to 6 months after the second vaccine dose (OR 8.2; P = .007, Fisher's exact test). We conclude that although allo-HSCT recipients achieve serum anti-RBD-S1 IgG against SARS-CoV-2 after 2 vaccinations, a deficiency of SARS-CoV-2-specific T-cell immunity may subsequently translate into insufficient humoral responses.


Assuntos
COVID-19 , Transplante de Células-Tronco Hematopoéticas , Anticorpos Antivirais , Vacina BNT162 , COVID-19/prevenção & controle , Vacinas contra COVID-19 , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Humanos , Imunidade Humoral , Imunoglobulina G , SARS-CoV-2 , Sobreviventes , Linfócitos T , Vacinação
14.
Mult Scler Relat Disord ; 56: 103288, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34634626

RESUMO

BACKGROUND: A two- to three-fold increase in the risk of multiple sclerosis (MS) after infectious mononucleosis (IM) has been observed in cohort and case control studies. However, this association has not been investigated prospectively from IM. It remains to be determined whether long-term immunospecific sequelae with features consistent with presymptomatic MS occur after IM. METHODS: Sera were obtained from individuals with acute IM from 2003-2007 (n = 42) and from the same individuals at a follow-up (FU) study approximately 10 years after IM. These were assayed for antibodies against a variety of Epstein-Barr virus (EBV) antigens, including gp350, a novel recombinant glycoprotein from the EBV envelope. Similarly, single-protein antigens were used to assess measles and varicella-zoster reactivity (Ncore and varicella-zoster glycoprotein E [VZVgE]). The FU study also included cerebrospinal fluid (CSF) samples from 21 of these individuals to test for IgG antibodies against the same viral antigens. As controls, CSF and serum samples were obtained from 15 EBV-seropositive volunteers who denied a history of IM, and serum samples were obtained from 24 EBV-seropositive blood donors. Anti-gp350, anti-Ncore and anti-VZVgE IgG levels were also analysed in sera and CSF samples from 22 persons with MS. RESULTS: The FU assays showed higher anti-gp350 IgG (p = 0.007, univariate) than among healthy controls, with no difference in serum anti-VCA or anti-EBNA1 IgG levels and no difference in anti-gp350 in the CSF samples. Anti-Ncore IgG and anti-VZVgE were higher in acute IM samples (p < 0.001 and p < 0.0001, respectively) than at FU, although anti-Ncore remained heightened in an age-adjusted analysis at FU (p = 0.014) compared to the control group. In the MS group, the serum anti-gp350 and anti-Ncore IgG levels were significantly higher than among the control group, but the anti-VZVgE levels were not. The CSF anti-gp350 and VZVgE levels were slightly higher among persons with MS than among the control group, whereas anti-Ncore IgG was markedly higher in persons with MS than in the control group. CONCLUSION: In the present study IM showed certain similarities with MS. Increased anti-gp350 reactivity persisted more than a decade after IM, reminiscent of the established increased anti-EBV reactivity in presymptomatic MS. Acute IM was associated with increased anti-measles and anti-VZV immunoreactivity, similar to the MRZ reaction in MS, with some evidence suggesting that this measles reactivity persisted after a decade.


Assuntos
Infecções por Vírus Epstein-Barr , Mononucleose Infecciosa , Esclerose Múltipla , Anticorpos Antivirais , Seguimentos , Herpesvirus Humano 4 , Humanos , Mononucleose Infecciosa/diagnóstico , Esclerose Múltipla/diagnóstico
15.
Fitoterapia ; 155: 105055, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34626739

RESUMO

The methanol root extract of Clerodendrum myricoides (Hochst.) Vatke afforded two new (1, 2) and two known (3, 4) iridoid glycosides. The structures of the isolated compounds were established based on NMR, IR, UV and MS data analyses. The crude extract and the isolated constituents were assayed for antiviral activity against the human respiratory syncytial virus (RSV) in human laryngeal epidermoid carcinoma (HEp-2) cells. The crude extract inhibited RSV infectivity at EC50 = 0.21 µg/ml, while it showed cytotoxicity against HEp-2 cells with CC50 = 9 µg/ml. Compound 2 showed 43.2% virus inhibition at 100 µM, while compounds 1 as well as 3 and 4 had only weak antiviral and cytotoxic activities.


Assuntos
Antivirais/farmacologia , Clerodendrum/química , Glicosídeos Iridoides/farmacologia , Vírus Sincicial Respiratório Humano/efeitos dos fármacos , Antivirais/isolamento & purificação , Linhagem Celular Tumoral , Humanos , Glicosídeos Iridoides/isolamento & purificação , Estrutura Molecular , Compostos Fitoquímicos/isolamento & purificação , Compostos Fitoquímicos/farmacologia , Extratos Vegetais , Raízes de Plantas/química , Ruanda
16.
Vaccine ; 39(40): 5866-5875, 2021 09 24.
Artigo em Inglês | MEDLINE | ID: mdl-34456075

RESUMO

Herpes simplex virus type 2 (HSV-2) is a common sexually transmitted disease that affects approximately 500 million individuals globally. There is currently no approved vaccine to prevent HSV-2 infection. EXCT4 is a truncated form of the mature glycoprotein G-2 (mgG-2) that unlike full mature form is secreted by expressing cells enabling it to be rapidly scaled up for production. The current study examined whether EXCT4 immunity in mice could be further enhanced through use of adjuvants. EXCT4 formulated with Advax-CpG adjuvant induced a strong Th1-type immune response characterized by interferon gamma (IFN-γ) and protected animals against a lethal genital challenge with HSV-2. This response was associated with reduced viral load in vaginal washes, spinal cord, and dorsal root ganglia. Together the results provide proof of concept that EXCT4 formulated with Advax-CpG adjuvant is a promising HSV-2 vaccine candidate warranting further investigation.


Assuntos
Herpes Genital , Vacinas , Animais , Feminino , Herpes Genital/prevenção & controle , Herpesvirus Humano 2 , Inulina/análogos & derivados , Camundongos , Proteínas do Envelope Viral
17.
Viruses ; 13(5)2021 05 12.
Artigo em Inglês | MEDLINE | ID: mdl-34065826

RESUMO

The contribution of virus components to liberation of herpes simplex virus type 2 (HSV-2) progeny virions from the surface of infected cells is poorly understood. We report that the HSV-2 mutant deficient in the expression of a mucin-like membrane-associated glycoprotein G (mgG) exhibited defect in the release of progeny virions from infected cells manifested by ~2 orders of magnitude decreased amount of infectious virus in a culture medium as compared to native HSV-2. Electron microscopy revealed that the mgG deficient virions were produced in infected cells and present at the cell surface. These virions could be forcibly liberated to a nearly native HSV-2 level by the treatment of cells with glycosaminoglycan (GAG)-mimicking oligosaccharides. Comparative assessment of the interaction of mutant and native virions with surface-immobilized chondroitin sulfate GAG chains revealed that while the mutant virions associated with GAGs ~fourfold more extensively, the lateral mobility of bound virions was much poorer than that of native virions. These data indicate that the mgG of HSV-2 balances the virus interaction with GAG chains, a feature critical to prevent trapping of the progeny virions at the surface of infected cells.


Assuntos
Glicoproteínas/metabolismo , Herpes Simples/virologia , Herpesvirus Humano 2/fisiologia , Proteínas do Envelope Viral/metabolismo , Liberação de Vírus , Membrana Celular/metabolismo , Células Cultivadas , Glicoproteínas/genética , Herpesvirus Humano 2/ultraestrutura , Interações Hospedeiro-Patógeno , Humanos , Mutação , Proteínas do Envelope Viral/genética , Vírion/ultraestrutura
18.
Eur J Neurol ; 28(9): 3072-3079, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34107122

RESUMO

BACKGROUND AND PURPOSE: Epstein-Barr virus (EBV) and human herpesvirus 6A (HHV-6A) are associated with increased risk of multiple sclerosis (MS). Conversely, infection with cytomegalovirus (CMV) has been suggested to reduce the risk of MS but supporting data from presymptomatic studies are lacking. Here, it was sought to increase the understanding of CMV in MS aetiology. METHODS: A nested case-control study was performed with presymptomatically collected blood samples identified through crosslinkage of MS registries and Swedish biobanks. Serological antibody response against CMV, EBV and HHV-6A was determined using a bead-based multiplex assay. Odds ratio (OR) with 95% confidence interval (CI) for CMV seropositivity as a risk factor for MS was calculated by conditional logistic regression and adjusted for EBV and HHV-6A seropositivity. Potential interactions on the additive scale were analysed by calculating the attributable proportion due to interaction (AP). RESULTS: Serum samples from 670 pairs of matched cases and controls were included. CMV seropositivity was associated with a reduced risk for MS (OR = 0.70, 95% CI 0.56-0.88, p = 0.003). Statistical interactions on the additive scale were observed between seronegativity for CMV and seropositivity against HHV-6A (AP 0.34, 95% CI 0.06-0.61) and EBV antigen EBNA-1 (amino acid 385-420) at age 20-39 years (AP 0.37, 95% CI 0.09-0.65). CONCLUSIONS: Cytomegalovirus seropositivity is associated with a decreased risk for MS. The protective role for CMV infection in MS aetiology is further supported by the interactions between CMV seronegativity and EBV and HHV-6A seropositivity.


Assuntos
Infecções por Vírus Epstein-Barr , Esclerose Múltipla , Adulto , Estudos de Casos e Controles , Citomegalovirus , Infecções por Vírus Epstein-Barr/complicações , Infecções por Vírus Epstein-Barr/epidemiologia , Herpesvirus Humano 4 , Humanos , Esclerose Múltipla/epidemiologia , Adulto Jovem
19.
Commun Biol ; 4(1): 185, 2021 02 10.
Artigo em Inglês | MEDLINE | ID: mdl-33568770

RESUMO

We present GSD_1.0, a high-quality domestic dog reference genome with chromosome length scaffolds and contiguity increased 55-fold over CanFam3.1. Annotation with generated and existing long and short read RNA-seq, miRNA-seq and ATAC-seq, revealed that 32.1% of lifted over CanFam3.1 gaps harboured previously hidden functional elements, including promoters, genes and miRNAs in GSD_1.0. A catalogue of canine "dark" regions was made to facilitate mapping rescue. Alignment in these regions is difficult, but we demonstrate that they harbour trait-associated variation. Key genomic regions were completed, including the Dog Leucocyte Antigen (DLA), T Cell Receptor (TCR) and 366 COSMIC cancer genes. 10x linked-read sequencing of 27 dogs (19 breeds) uncovered 22.1 million SNPs, indels and larger structural variants. Subsequent intersection with protein coding genes showed that 1.4% of these could directly influence gene products, and so provide a source of normal or aberrant phenotypic modifications.


Assuntos
Perfilação da Expressão Gênica/normas , Variação Genética , Genoma , Genômica/normas , Fatores de Transcrição/genética , Transcriptoma , Animais , Cães , Feminino , Genótipo , Mutação INDEL , Fenótipo , Polimorfismo de Nucleotídeo Único , RNA-Seq/normas , Valores de Referência , Fatores de Transcrição/metabolismo
20.
Vaccine ; 39(7): 1035-1038, 2021 02 12.
Artigo em Inglês | MEDLINE | ID: mdl-33483213

RESUMO

INTRODUCTION: Our aim was to assess response and side effects of 4 doses of TBE vaccine to patients (pts) after allo- and autologous stem cell transplantation (SCT). PATIENTS: Included were 104 pts with leukaemia, myeloma and lymphoma, median age 61 yrs. METHODS: Vaccine (FSME-Immun®) was given at 9, 10, 12, and 21 months post-transplant. Serum samples were obtained before and after vaccinations. Healthy controls (n = 27) received 3 vaccinations. Assessments of TBE specific IgG antibodies were performed by Enzygnost anti-TBE ELISA test (Siemens, Sweden). RESULTS: Antibody levels (>12 U/mL; "seropositivity") were seen in 77% and 80% of pts after allo- and autoSCT; IgG levels; 89 vs 94 U/mL. Ongoing chronic GvHD and immunosuppression (n = 29) was associated with sero-negativity in the last sample (p = 0.007). All controls (n = 27) developed protective antibody levels. CONCLUSIONS: TBE vaccination was safe, and 4 doses starting 9 months post-SCT, induced seropositivity in a vast majority of pts.


Assuntos
Vírus da Encefalite Transmitidos por Carrapatos , Encefalite Transmitida por Carrapatos , Transplante de Células-Tronco Hematopoéticas , Vacinas Virais , Anticorpos Antivirais , Encefalite Transmitida por Carrapatos/prevenção & controle , Humanos , Pessoa de Meia-Idade , Transplante Autólogo , Vacinação
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