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1.
FASEB J ; 37(4): e22846, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36856983

RESUMO

Colchicine is a broad-acting anti-inflammatory agent that has attracted interest for repurposing in atherosclerotic cardiovascular disease. Here, we studied its ability at a human equivalent dose of 0.5 mg/day to modify plaque formation and composition in murine atherosclerosis and investigated its actions on macrophage responses to atherogenic stimuli in vitro. In atherosclerosis induced by high-cholesterol diet, Apoe-/- mice treated with colchicine had 50% reduction in aortic oil Red O+ plaque area compared to saline control (p = .001) and lower oil Red O+ staining of aortic sinus lesions (p = .03). In vitro, addition of 10 nM colchicine inhibited foam cell formation from murine and human macrophages after treatment with oxidized LDL (ox-LDL). Mechanistically, colchicine downregulated glycosylation and surface expression of the ox-LDL uptake receptor, CD36, and reduced CD36+ staining in aortic sinus plaques. It also decreased macrophage uptake of cholesterol crystals, resulting in lower intracellular lysosomal activity, inhibition of the NLRP3 inflammasome, and reduced secretion of IL-1ß and IL-18. Colchicine's anti-atherosclerotic actions were accentuated in a mouse model of unstable plaque induced by carotid artery tandem stenosis surgery, where it decreased lesion size by 48% (p = .01), reduced lipid (p = .006) and necrotic core area (p = .007), increased collagen content and cap-to-necrotic core ratio (p = .05), and attenuated plaque neutrophil extracellular traps (p < .001). At low dose, colchicine's effects were not accompanied by the evidence of microtubule depolymerization. Together, these results show that colchicine exerts anti-atherosclerotic and plaque-stabilizing effects at low dose by inhibiting foam cell formation and cholesterol crystal-induced inflammation. This provides a new framework to support its repurposing for atherosclerotic cardiovascular disease.


Assuntos
Aterosclerose , Doenças Cardiovasculares , Estenose das Carótidas , Humanos , Animais , Camundongos , Células Espumosas , Colchicina , Colesterol
2.
Aust N Z J Psychiatry ; : 48674241248357, 2024 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-38711323

RESUMO

OBJECTIVE: The objective was to describe mental health service and psychotropic medicine use among a cohort of Aboriginal young people and quantify their relation to sociodemographic, family and health factors. METHODS: In a prospective cohort study with data linkage, 892 Aboriginal children aged 0-17 years living in urban and regional areas of New South Wales, Australia, were included. We assessed mental health-related service use, paediatric service use and psychotropic medicine dispensing claims covered by the Australian Government Medicare Benefits Schedule and the Pharmaceutical Benefits Scheme from July 2012 to June 2017. RESULTS: Most children (71%) did not have a record of mental health service or psychotropic medication use. 18.7% had ⩾1 mental health-related service claim; 26.7% had ⩾1 paediatric service claim; and 20.3% had ⩾1 psychotropic medicine dispensing claim. General practitioner services were the most accessed mental health-related service (17.4%) and 12.7% had been dispensed attention-deficit hyperactivity disorder medicines. Child characteristics associated with treatment included emotional and behavioural problems (prevalence ratio: 1.97, 95% confidence interval = [1.46, 2.64] for mental health services; prevalence ratio: 2.87, 95% confidence interval = [2.07, 3.96] for medicines) and risky behaviour (prevalence ratio: 1.56, 95% confidence interval = [1.12, 2.16] for mental health services; prevalence ratio: 2.28, 95% confidence interval = [1.54, 3.37] for medicines). Parent-related factors included chronic illness (prevalence ratio: 1.42, 95% confidence interval = [1.03, 1.95] for mental health services; prevalence ratio: 2.00, 95% confidence interval = [1.49, 2.69] for medicines) and functional limitations (prevalence ratio: 1.61, 95% confidence interval = [1.16, 2.24] for mental health services; prevalence ratio: 1.86, 95% confidence interval = [1.34, 2.59] for medicines). CONCLUSIONS: Most Aboriginal children and young people did not have claims for mental health services or medicines. Aboriginal children with emotional and behavioural problems, or parents with health problems were more likely to have mental health service or medicine claims.

3.
Cancer Causes Control ; 34(10): 909-926, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37329444

RESUMO

PURPOSE: Older age, risks from pre-existing health conditions and socio-economic disadvantage are negatively related to the prospects of an early-stage cancer diagnosis. With older Aboriginal Australians having an elevated prevalence of these underlying factors, this study examines the potential for the mitigating effects of more frequent contact with general practitioners (GPs) in ensuring local-stage at diagnosis. METHODS: We compared the odds of local vs. more advanced stage at diagnosis of solid tumours according to GP contact, using linked registry and administrative data. Results were compared between Aboriginal (n = 4,084) and non-Aboriginal (n = 249,037) people aged 50 + years in New South Wales with a first diagnosis of cancer in 2003-2016. RESULTS: Younger age, male sex, having less area-based socio-economic disadvantage, and fewer comorbid conditions in the 12 months before diagnosis (0-2 vs. 3 +), were associated with local-stage in fully-adjusted structural models. The odds of local-stage with more frequent GP contact (14 + contacts per annum) also differed by Aboriginal status, with a higher adjusted odds ratio (aOR) of local-stage for frequent GP contact among Aboriginal people (aOR = 1.29; 95% CI 1.11-1.49) but not among non-Aboriginal people (aOR = 0.97; 95% CI 0.95-0.99). CONCLUSION: Older Aboriginal Australians diagnosed with cancer experience more comorbid conditions and more socioeconomic disadvantage than other Australians, which are negatively related to diagnosis at a local-cancer stage. More frequent GP contact may act to partly offset this among the Aboriginal population of NSW.


Assuntos
Medicina Geral , Neoplasias , Humanos , Masculino , Austrália/epidemiologia , Povos Aborígenes Australianos e Ilhéus do Estreito de Torres , Neoplasias/diagnóstico , Neoplasias/epidemiologia , Neoplasias/patologia , New South Wales/epidemiologia , Feminino , Pessoa de Meia-Idade
4.
FASEB J ; 36(2): e22154, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-35032419

RESUMO

Eukaryotic elongation factor 2 kinase (eEF2K) is an atypical protein kinase that controls protein synthesis in cells under stress. Although well studied in cancer, less is known about its roles in chronic inflammatory diseases. Here, we examined its regulation of macrophage cholesterol handling in the context of atherosclerosis. eEF2K mRNA expression and protein activity were upregulated in murine bone marrow-derived macrophages (BMDMs) exposed to oxidized low-density lipoprotein cholesterol (oxLDL). When incubated with oxLDL, BMDMs from eEF2K knockout (Eef2k-/- ) mice formed fewer Oil Red O+ foam cells than Eef2k+/+ BMDMs (12.5% ± 2.3% vs. 32.3% ± 2.0%, p < .01). Treatment with a selective eEF2K inhibitor, JAN-384, also decreased foam cell formation for C57BL/6J BMDMs and human monocyte-derived macrophages. Disabling eEF2K selectively decreased protein expression of the CD36 cholesterol uptake receptor, mediated by a reduction in the proportion of translationally active Cd36 mRNA. Eef2k-/- mice bred onto the Ldlr-/- background developed aortic sinus atherosclerotic plaques that were 30% smaller than Eef2k+/+ -Ldlr-/- mice after 16 weeks of high cholesterol diet (p < .05). Although accompanied by a reduction in plaque CD36+ staining (p < .05) and lower CD36 expression in circulating monocytes (p < .01), this was not associated with reduced lipid content in plaques as measured by oil red O staining. Finally, EEF2K and CD36 mRNA levels were higher in blood mononuclear cells from patients with coronary artery disease and recent myocardial infarction compared to healthy controls without coronary artery disease. These results reveal a new role for eEF2K in translationally regulating CD36 expression and foam cell formation in macrophages. Further studies are required to explore therapeutic targeting of eEF2K in atherosclerosis.


Assuntos
Antígenos CD36/metabolismo , Quinase do Fator 2 de Elongação/metabolismo , Células Espumosas/metabolismo , Animais , Aterosclerose/metabolismo , Colesterol/metabolismo , Doença da Artéria Coronariana/metabolismo , Feminino , Humanos , Leucócitos Mononucleares/metabolismo , Macrófagos/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Monócitos/metabolismo , Placa Aterosclerótica/metabolismo , RNA Mensageiro/metabolismo , Transdução de Sinais/fisiologia
5.
Transfusion ; 63(8): 1463-1471, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37357984

RESUMO

BACKGROUND: Translation of research knowledge is critical to ensure transfusion medicine policies and practices reflect current evidence and so effectively support the health of blood donors and recipients, as well as ensuring ongoing blood supply. The aim of this study was to investigate the barriers and facilitators of knowledge translation (KT) among transfusion medicine researchers and determine what KT supports are needed. STUDY DESIGN AND METHODS: An anonymous, cross-sectional survey was distributed by emailing corresponding authors of papers in four major blood journals, emailing grant recipients in the area of transfusion medicine, posting on social media, and through an international blood operator network. RESULTS: The final sample included 105 researchers. Participants had a positive orientation toward KT, with few perceiving KT as not relevant to their research or beneficial for their careers. However, many reported facing difficulties practicing KT due to time constraints, competing priorities, or lack of funds or resources. Fostering relationships with stakeholders was seen as a key facilitator of KT but a number of researchers expressed difficulties engaging and communicating with them. Collaboration opportunities, protected time for KT, and access to KT resources were some of the supports researchers felt were required to help their KT efforts. CONCLUSION: To minimize the knowledge to practice gap in transfusion medicine and ensure findings from research lead to improved outcomes, organizations need to support researchers in their KT efforts and facilitate interactions between researchers and research end-users.


Assuntos
Medicina Transfusional , Humanos , Estudos Transversais , Ciência Translacional Biomédica , Pesquisa Translacional Biomédica , Política de Saúde
6.
J Cancer Educ ; 38(1): 146-152, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-34581972

RESUMO

Little is known about the level of knowledge and awareness with regard to human papillomavirus (HPV) and its associated risks among adolescents and young adults in South Africa. A cross-sectional study was conducted to assess HPV infection and associated risks knowledge level among learners attending high schools in the Eastern Cape Province of South Africa. Learners (females and males) attending five selected schools in the Eastern Cape Province of South Africa participated. The intervention included knowledge pre-assessment, education through structured lecture, and post-education assessment. Self-administered questionnaires were used in both pre and post-intervention assessments. There were 2652 learners, who participated, with a median age of 18 years (IQR: 16-19). Female participants constituted 53.58% (1421/2652), and male participants were 46.42% (1231/2652). Before education intervention, only 4.08% (107/2623) of learners ever heard about HPV and 3.31% (87/2626) about HPV vaccination. Only 9.36% (247/2638) and 9.34% (246/2635) knew that HPV infection is sexually transmitted and associated with cervical cancer development, respectively. After education intervention, knowledge about HPV among learners increased significantly (p < 0.001). In post-education assessment, female high school learners were 66% more likely to acquire HPV knowledge than males (OR, 1.66; 95% CI, 1.40-1.97; p < 0.0001). Exposure to an educational intervention significantly increased learners' knowledge levels. The increasing burden of cervical cancer and other HPV-associated cancers are public health problems of concern. Therefore, the evaluation of educational interventions for increasing knowledge on HPV-associated diseases is necessary for low-resource settings with a high burden of cervical cancer.


Assuntos
Infecções por Papillomavirus , Vacinas contra Papillomavirus , Neoplasias do Colo do Útero , Adolescente , Adulto Jovem , Humanos , Masculino , Feminino , Adulto , Papillomavirus Humano , Infecções por Papillomavirus/prevenção & controle , Neoplasias do Colo do Útero/prevenção & controle , África do Sul , Estudos Transversais , Instituições Acadêmicas , Inquéritos e Questionários , Vacinas contra Papillomavirus/uso terapêutico , Conhecimentos, Atitudes e Prática em Saúde
7.
Heart Lung Circ ; 32(2): 224-231, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36344392

RESUMO

BACKGROUND: Transcatheter aortic valve implantation (TAVI) is an established therapy for the treatment of aortic valve disease in appropriately selected patients. Previous studies using the self-expanding Portico transcatheter heart valve (THV), (Abbott Structural Heart, St Paul, MN, USA) have demonstrated the technical feasibility of this system albeit in the hands of relatively inexperienced Portico users. The objective of this study was to assess the real-world safety and efficacy of the Portico THV (with and without the FlexNav delivery system, Abbott Structural Heart) at the 30-day timepoint in an Australian cohort. METHODS AND RESULTS: This study was a retrospective real-world cohort analysis of 269 consecutive patients with severe aortic valve disease who underwent TAVI at multiple centres within Australia between February 2015 and April 2021. Of the 269 patients, 51.7% were female, mean Society of Thoracic Surgeons (STS) score was 5.2 (±6.8) and 98.5% had successful implantations. Thirty (30)-day post-implantation all-cause mortality was observed in one (0.4%) patient, major vascular complications in two (0.7%) patients, more-than-mild paravalvular leak in six (2.2%) patients and requirement for new permanent pacemaker implantation in 27 (10.2%) patients. Haemodynamic parameters at 30 days included mean effective orifice area (EOA) of 2.3 (±0.9) cm2 and mean aortic valve gradient (AVG) of 9.6 (±6.2) mmHg. CONCLUSION: This analysis of the Portico THV in a real-world setting suggested that the system is associated with satisfactory safety and efficacy parameters. Previously published datasets may not have found similar findings owing to lower operator experience with the Portico THV system.


Assuntos
Valvopatia Aórtica , Estenose da Valva Aórtica , Próteses Valvulares Cardíacas , Substituição da Valva Aórtica Transcateter , Humanos , Feminino , Masculino , Valva Aórtica/cirurgia , Estenose da Valva Aórtica/diagnóstico , Estenose da Valva Aórtica/cirurgia , Estudos Retrospectivos , Resultado do Tratamento , Austrália/epidemiologia , Substituição da Valva Aórtica Transcateter/métodos , Valvopatia Aórtica/cirurgia , Desenho de Prótese
8.
J Gen Virol ; 103(5)2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35594121

RESUMO

In vivo nucleic expression technologies using DNA or mRNA offer several advantages for recombinant gene expression. Their inherent ability to generate natively expressed recombinant proteins and antigens allows these technologies to mimic foreign gene expression without infection. Furthermore, foreign nucleic acid fragments have an inherent ability to act as natural immune adjuvants and stimulate innate pathogen- and DNA damage-associated receptors that are responsible for activating pathogen-associated molecular pattern (PAMP) and DNA damage-associated molecular pattern (DAMP) signalling pathways. This makes nucleic-acid-based expression technologies attractive for a wide range of vaccine and oncolytic immunotherapeutic uses. Recently, RNA vaccines have demonstrated their efficacy in generating strong humoral and cellular immune responses for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). DNA vaccines, which are more stable and easier to manufacture, generate similar immune responses to RNA, but typically exhibit lower immunogenicity. Here we report on a novel method of constructing self-amplifying DNA expression vectors that have the potential to amplify and enhance gene/antigen expression at a cellular level by increasing per cell gene copy numbers, boost genomic adjuvating effects and mitigate through replication many of the problems faced by non-replicating vectors such as degradation, methylation and gene silencing. These vectors employ a viral origin rolling circle replication cycle in mammalian host cells that amplifies the vector and gene of interest (GOI) copy number, maintaining themselves as nuclear episomes. We show that these vectors maintain persistently elevated GOI expression levels at the cellular level and induce morphological cellular alterations synonymous with increased cellular stress.


Assuntos
COVID-19 , Circovirus , Vacinas de DNA , Animais , Circovirus/genética , Vetores Genéticos/genética , Mamíferos , SARS-CoV-2 , Vacinas de DNA/genética
9.
Biotechnol Bioeng ; 119(10): 2919-2937, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35781691

RESUMO

Heterologous glycoprotein production relies on host glycosylation-dependent folding. When the biosynthetic machinery differs from the usual expression host, there is scope to remodel the assembly pathway to enhance glycoprotein production. Here we explore the integration of chaperone coexpression with glyco-engineering to improve the production of a model HIV-1 envelope antigen. Calreticulin was coexpressed to support protein folding together with Leishmania major STT3D oligosaccharyltransferase, to improve glycan occupancy, RNA interference to suppress the formation of truncated glycans, and Nicotiana benthamiana plants lacking α1,3-fucosyltransferase and ß1,2-xylosyltransferase was used as an expression host to prevent plant-specific complex N-glycans forming. This approach reduced the formation of undesired aggregates, which predominated in the absence of glyco-engineering. The resulting antigen also exhibited increased glycan occupancy, albeit to a slightly lower level than the equivalent mammalian cell-produced protein. The antigen was decorated almost exclusively with oligomannose glycans, which were less processed compared with the mammalian protein. Immunized rabbits developed comparable immune responses to the plant-produced and mammalian cell-derived antigens, including the induction of autologous neutralizing antibodies when the proteins were used to boost DNA and modified vaccinia Ankara virus-vectored vaccines. This study demonstrates that engineering glycosylation-directed folding offers a promising route to enhance the production of complex viral glycoproteins in plants.


Assuntos
Anticorpos Neutralizantes , Infecções por HIV , Animais , Antígenos Virais/metabolismo , Glicoproteínas/genética , Glicoproteínas/metabolismo , Glicosilação , Anticorpos Anti-HIV , Mamíferos/metabolismo , Polissacarídeos/metabolismo , Coelhos
10.
Nanotechnology ; 33(48)2022 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-35882111

RESUMO

Two-component self-assembling virus-like particles (VLPs) are promising scaffolds for achieving high-density display of HIV-1 envelope (gp140) trimers, which can improve the induction of neutralising antibodies (NAbs). In this study gp140 was displayed on the surface of VLPs formed by the AP205 phage coat protein. The CAP256 SU gp140 antigen was selected as the patient who this virus was isolated from developed broadly neutralising antibodies (bNAbs) shortly after superinfection with this virus. The CAP256 SU envelope is also sensitive to several bNAbs and has shown enhanced reactivity for certain bNAb precursors. A fusion protein comprising the HIV-1 CAP256 SU gp140 and the SpyTag (ST) (gp140-ST) was produced in HEK293 cells, and trimers were purified to homogeneity using gel filtration. SpyCatcher (SC)-AP205 VLPs were produced inEscherichia coliand purified by ultracentrifugation. The gp140-ST trimers and the SC-AP205 VLPs were mixed in varying molar ratios to generate VLPs displaying the glycoprotein (AP205-gp140-ST particles). Dynamic light scattering, negative stain electron microscopy and 2D classification indicated that gp140-ST was successfully bound to the VLPs, although not all potential binding sites were occupied. The immunogenicity of the coupled VLPs was evaluated in a pilot study in rabbits. One group was injected four times with coupled VLPs, and the second group was primed with DNA vaccines expressing Env and a mosaic Gag, followed by modified vaccinia Ankara expressing the same antigens. The animals were then boosted twice with coupled VLPs. Encouragingly, gp140-ST displayed on SC-AP205 VLPs was an effective boost to heterologously primed rabbits, leading to induction of autologous Tier 2 neutralising antibodies in 2/5 rabbits. However, four inoculations of coupled VLPs alone failed to elicit any Tier 2 antibodies. These results demonstrate that the native-like structure of HIV-1 envelope trimers and selection of a geometrically-suitable nanoparticle scaffold to achieve a high-density display of the trimers are important considerations that could improve the effect of nanoparticle-displayed gp140.


Assuntos
HIV-1 , Nanopartículas , Vacinas , Animais , Anticorpos Amplamente Neutralizantes , Células HEK293 , Humanos , Projetos Piloto , Coelhos , Produtos do Gene env do Vírus da Imunodeficiência Humana/química , Produtos do Gene env do Vírus da Imunodeficiência Humana/genética
11.
Transfusion ; 61(6): 1772-1779, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33797069

RESUMO

BACKGROUND: Knowledge translation focuses on the transfer of research findings into policy and practice. To provide insight into the state of knowledge translation in blood donor research, we undertook a rapid review of a key research area in the field with high potential for translation, vasovagal reactions (VVRs). We examined the number and nature of VVR-related studies to determine the availability of research evidence, and mapped the included articles along the research-to-practice trajectory using the Knowledge to Action framework. STUDY DESIGN AND METHODS: PubMed, PsycINFO, CINAHL, and EMBASE were searched for peer-reviewed journal articles from inception to October 2019 using the terms blood don* AND vasovagal OR faint* OR syncope. RESULTS: A total of 176 articles met our inclusion criteria. Studies relating to VVRs increased substantially from 1942 to 2019, with 84% published in the last 20 years. Articles were predominately observation (non-intervention) studies (117; 66%), followed by intervention (knowledge inquiry) studies (31; 18%) and review (knowledge synthesis) studies (20; 11%). The evidence from intervention research was limited, with 14 strategies tested in 31 studies and often by the same research groups. Only 5 (3%) implementation and evaluation studies were found; all focused on evaluating the effects of a newly introduced intervention on VVR rates through uncontrolled or cross-sectional study designs. DISCUSSION: VVR research is in the early stages of knowledge translation. More intervention research is needed to provide a robust evidence base as well as more published implementation research to share knowledge of translating research into policy and practice.


Assuntos
Doadores de Sangue , Síncope Vasovagal/etiologia , Humanos , Fatores de Risco , Pesquisa Translacional Biomédica
12.
J Gen Virol ; 101(6): 645-650, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32391749

RESUMO

Lumpy skin disease virus (LSDV), a Capripoxvirus, is of economic importance in the cattle industry and is controlled by vaccination. A comparison was made of the host response to the two LSDV vaccines Neethling and Herbivac LS, with reference to the well-studied Orthopoxvirus, modified vaccinia Ankara (MVA), in a mouse model. Because the vaccines differ at the superoxide dismutase homologue (SOD) gene locus, recombinant SOD knock-out and knock-in nLSDV vaccines were constructed and all four vaccines were tested for the induction and inhibition of apoptosis. The SOD homologue was associated both with induction of apoptosis as well as inhibition of camptothecin-induced apoptosis. Histological analysis of chorioallantoic membranes of fertilized hens' eggs infected with the four different vaccines indicated marked mesodermal proliferation associated with vaccines containing the full-length SOD homologue as well as increased immune cell infiltration. Our findings suggest that the SOD homologue may influence vaccine immunogenicity.


Assuntos
Apoptose/genética , Interações Hospedeiro-Patógeno/genética , Doença Nodular Cutânea/genética , Doença Nodular Cutânea/virologia , Vírus da Doença Nodular Cutânea/genética , Superóxido Dismutase/genética , Transcrição Gênica/genética , Animais , Apoptose/imunologia , Bovinos , Galinhas/imunologia , Galinhas/virologia , Feminino , Doença Nodular Cutânea/imunologia , Vírus da Doença Nodular Cutânea/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Superóxido Dismutase/imunologia , Transcrição Gênica/imunologia , Vacinação/métodos , Vacinas Atenuadas/imunologia , Vaccinia virus/genética , Vaccinia virus/imunologia , Vacinas Virais/imunologia
13.
J Mol Evol ; 88(5): 453-462, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32385625

RESUMO

We use all the currently known 405 Papillomavirus (PV) sequences, 343 curated PV sequences from both humans and animals from the PAVE data base, to analyse the recombination dynamics of these viruses at the whole genome levels. After showing some evidence of human and non-human primate PV recombination, we report a comprehensive recombination analysis of all currently known 82 Alphapapillomaviruses (Alpha-PVs). We carried out an exploratory study and found novel recombination events between High-Risk HPV Types and Macaca fascicularis PV1 (MfPV1), Macaca Fuscata PV2 (MfuPV2) and Pan Paniscus PV1 (PpPV1) Papillomaviruses. This is the first evidence of interactions between PVs from different hosts and hence postulates the likelihood of ancient host switching among Alpha-PVs. Notwithstanding these results should be interpreted with caution because the major and minor parents indicated by RDP4 program are simply the sequences in the alignment that most closely resemble the actual parents. We found statistically significant differences between the phylogenies of the PV sequences with recombination regions and PV sequences without recombination regions using the Shimodaira-Hasegawa phylogenetic incongruence testing. We show that not more than 76MYA Alpha-PVs were in the same biological niche, a pre-requisite for recombination, and as the hosts evolved and diversified, the viruses adapted to specific host niches which eventually led to coevolution with specific hosts before speciation of primate species. Thus providing evidence that in ancient times no earlier than the Cretaceous period of the Mesozoic age, Alpha-PVs recombined and switched hosts, but whether this host switching is occurring currently is unknown. However, a clearer picture of the PVs evolutionary landscape can only be achieved with the incremental discovery of PV sequences, especially from the animal kingdom.


Assuntos
Alphapapillomavirus/classificação , Filogenia , Recombinação Genética , Alphapapillomavirus/genética , Animais , Genoma Viral , Especificidade de Hospedeiro , Primatas/virologia
14.
Plant Biotechnol J ; 18(10): 2109-2117, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32096288

RESUMO

Plant molecular farming (PMF) is rapidly gaining traction as a viable alternative to the currently accepted paradigm of producing biologics. While the platform is potentially cheaper and more scalable than conventional manufacturing systems, expression yields and appropriate post-translational modifications along the plant secretory pathway remain a challenge for certain proteins. Viral fusion glycoproteins in particular are often expressed at low yields in plants and, in some cases, may not be appropriately processed. Recently, however, transiently or stably engineering the host plant has shown promise as a strategy for producing heterologous proteins with more complex maturation requirements. In this study we investigated the co-expression of a suite of human chaperones to improve the production of a human immunodeficiency virus (HIV) type 1 soluble gp140 vaccine candidate in Nicotiana benthamiana plants. The co-expression of calreticulin (CRT) resulted in a dramatic increase in Env expression and ameliorated the endoplasmic reticulum (ER) stress response - as evidenced by lower transcript abundance of representative stress-responsive genes. The co-expression of CRT similarly improved accumulation of glycoproteins from Epstein-Barr virus (EBV), Rift Valley fever virus (RVFV) and chikungunya virus (CHIKV), suggesting that the endogenous chaperone machinery may impose a bottleneck for their production. We subsequently successfully combined the co-expression of human CRT with the transient expression of human furin, to enable the production of an appropriately cleaved HIV gp140 antigen. These transient plant host engineering strategies are a promising approach for the production of high yields of appropriately processed and cleaved viral glycoproteins.

15.
J Virol ; 93(8)2019 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-30760570

RESUMO

A vaccine regimen that elicits broadly neutralizing antibodies (bNAbs) is a major goal in HIV-1 vaccine research. In this study, we assessed the immunogenicity of the CAP256 superinfecting viral envelope (CAP256 SU) protein delivered by modified vaccinia virus Ankara (MVA) and DNA vaccines in different prime-boost combinations followed by a soluble protein (P) boost. The envelope protein (Env) contained a flexible glycine linker and I559P mutation. Trimer-specific bNAbs PGT145, PG16, and CAP256 VRC26_08 efficiently bound to the membrane-bound CAP256 envelope expressed on the surface of cells transfected or infected with the DNA and MVA vaccines. The vaccines were tested in two different vaccination regimens in rabbits. Both regimens elicited autologous tier 2 neutralizing antibodies (NAbs) and high-titer binding antibodies to the matching CAP256 Env and CAP256 V1V2 loop scaffold. The immunogenicity of DNA and MVA vaccines expressing membrane-bound Env alone was compared to that of Env stabilized in a more native-like conformation on the surface of Gag virus-like particles (VLPs). The inclusion of Gag in the DNA and MVA vaccines resulted in earlier development of tier 2 NAbs for both vaccination regimens. In addition, a higher proportion of the rabbits primed with DNA and MVA vaccines that included Gag developed tier 2 NAbs than did those primed with vaccine expressing Env alone. Previously, these DNA and MVA vaccines expressing subtype C mosaic HIV-1 Gag were shown to elicit strong T cell responses in mice. Here we show that when the CAP256 SU envelope protein is included, these vaccines elicit autologous tier 2 NAbs.IMPORTANCE A vaccine is urgently needed to combat HIV-1, particularly in sub-Saharan Africa, which remains disproportionately affected by the AIDS pandemic and accounts for the majority of new infections and AIDS-related deaths. In this study, two different vaccination regimens were compared. Rabbits that received two DNA primes followed by two modified vaccinia virus Ankara (MVA) and two protein inoculations developed better immune responses than those that received two MVA and three protein inoculations. In addition, DNA and MVA vaccines that expressed mosaic Gag VLPs presenting a stabilized Env antigen elicited better responses than Env alone, which supports the inclusion of Gag VLPs in an HIV-1 vaccine.


Assuntos
Vacinas contra a AIDS , Anticorpos Neutralizantes/imunologia , Anticorpos Anti-HIV/imunologia , HIV-1 , Imunização Secundária , Vacinas de DNA , Vaccinia virus , Produtos do Gene env do Vírus da Imunodeficiência Humana , Vacinas contra a AIDS/genética , Vacinas contra a AIDS/imunologia , Animais , Feminino , Células HEK293 , HIV-1/genética , HIV-1/imunologia , Humanos , Coelhos , Vacinas de DNA/genética , Vacinas de DNA/imunologia , Produtos do Gene env do Vírus da Imunodeficiência Humana/genética , Produtos do Gene env do Vírus da Imunodeficiência Humana/imunologia
16.
PLoS Pathog ; 14(7): e1007182, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-30048550

RESUMO

Future HIV vaccines are expected to induce effective Th1 cell-mediated and Env-specific antibody responses that are necessary to offer protective immunity to HIV infection. However, HIV infections are highly prevalent in helminth endemic areas. Helminth infections induce polarised Th2 responses that may impair HIV vaccine-generated Th1 responses. In this study, we tested if Schistosoma mansoni (Sm) infection altered immune responses to SAAVI candidate HIV vaccines (DNA and MVA) and an HIV-1 gp140 Env protein vaccine (gp140) and whether parasite elimination by chemotherapy or the presence of Sm eggs (SmE) in the absence of active infection influenced the immunogenicity of these vaccines. In addition, we evaluated helminth-associated pathology in DNA and MVA vaccination groups. Mice were chronically infected with Sm and vaccinated with DNA+MVA in a prime+boost combination or MVA+gp140 in concurrent combination regimens. Some Sm-infected mice were treated with praziquantel (PZQ) prior to vaccinations. Other mice were inoculated with SmE before receiving vaccinations. Unvaccinated mice without Sm infection or SmE inoculation served as controls. HIV responses were evaluated in the blood and spleen while Sm-associated pathology was evaluated in the livers. Sm-infected mice had significantly lower magnitudes of HIV-specific cellular responses after vaccination with DNA+MVA or MVA+gp140 compared to uninfected control mice. Similarly, gp140 Env-specific antibody responses were significantly lower in vaccinated Sm-infected mice compared to controls. Treatment with PZQ partially restored cellular but not humoral immune responses in vaccinated Sm-infected mice. Gp140 Env-specific antibody responses were attenuated in mice that were inoculated with SmE compared to controls. Lastly, Sm-infected mice that were vaccinated with DNA+MVA displayed exacerbated liver pathology as indicated by larger granulomas and increased hepatosplenomegaly when compared with unvaccinated Sm-infected mice. This study shows that chronic schistosomiasis attenuates both HIV-specific T-cell and antibody responses and parasite elimination by chemotherapy may partially restore cellular but not antibody immunity, with additional data suggesting that the presence of SmE retained in the tissues after antihelminthic therapy contributes to lack of full immune restoration. Our data further suggest that helminthiasis may compromise HIV vaccine safety. Overall, these findings suggested a potential negative impact on future HIV vaccinations by helminthiasis in endemic areas.


Assuntos
Vacinas contra a AIDS/imunologia , Infecções por HIV/prevenção & controle , Esquistossomose mansoni/imunologia , Esquistossomose mansoni/patologia , Produtos do Gene env do Vírus da Imunodeficiência Humana/imunologia , Animais , Anticorpos Neutralizantes/imunologia , Modelos Animais de Doenças , Feminino , Anticorpos Anti-HIV/imunologia , HIV-1/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Vacinas de DNA/imunologia , Vacinas Virais/imunologia
17.
BMC Microbiol ; 20(1): 78, 2020 04 06.
Artigo em Inglês | MEDLINE | ID: mdl-32252632

RESUMO

BACKGROUND: To date, the microbiota of the human penis has been studied mostly in connection with circumcision, HIV risk and female partner bacterial vaginosis (BV). These studies have shown that male circumcision reduces penile anaerobic bacteria, that greater abundance of penile anaerobic bacteria is correlated with increased cytokine levels and greater risk of HIV infection, and that the penile microbiota is an important harbour for BV-associated bacteria. While circumcision has been shown to significantly reduce the risk of acquiring human papillomavirus (HPV) infection, the relationship of the penile microbiota with HPV is still unknown. In this study, we examined the penile microbiota of HPV-infected men as well as the impact of HIV status. RESULTS: The penile skin microbiota of 238 men from Cape Town (South Africa) were profiled using Illumina sequencing of the V3-V4 hypervariable regions of the 16S rRNA gene. Corynebacterium and Prevotella were found to be the most abundant genera. Six distinct community state types (CSTs) were identified. CST-1, dominated by Corynebacterium, corresponded to less infections with high-risk HPV (HR-HPV) relative to CSTs 2-6. Men in CST-5 had greater relative abundances of Prevotella, Clostridiales, and Porphyromonas and a lower relative abundance of Corynebacterium. Moreover, they were significantly more likely to have HPV or HR-HPV infections than men in CST-1. Using a machine learning approach, we identified greater relative abundances of the anaerobic BV-associated bacteria (Prevotella, Peptinophilus, and Dialister) and lower relative abundance of Corynebacterium in HR-HPV-infected men compared to HR-HPV-uninfected men. No association was observed between HIV and CST, although the penile microbiota of HIV-infected men had greater relative abundances of Staphylococcus compared to HIV-uninfected men. CONCLUSIONS: We found significant differences in the penile microbiota composition of men with and without HPV and HIV infections. HIV and HR-HPV infections were strongly associated with greater relative abundances of Staphylococcus and BV-associated bacterial taxa (notably Prevotella, Peptinophilus and Dialister), respectively. It is possible that these taxa could increase susceptibility to HIV and HR-HPV acquisition, in addition to creating conditions in which infections persist. Further longitudinal studies are required to establish causal relationships and to determine the extent of the effect.


Assuntos
Bactérias/classificação , Infecções por HIV/epidemiologia , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Infecções por Papillomavirus/epidemiologia , Pênis/microbiologia , Adulto , Bactérias/genética , Bactérias/isolamento & purificação , Circuncisão Masculina/efeitos adversos , Estudos Transversais , DNA Ribossômico/genética , Infecções por HIV/microbiologia , Humanos , Estudos Longitudinais , Aprendizado de Máquina , Masculino , Microbiota , Infecções por Papillomavirus/microbiologia , Filogenia , RNA Ribossômico 16S/genética , Estudos Retrospectivos , Análise de Sequência de DNA , África do Sul
18.
Arch Virol ; 165(5): 1207-1210, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32140837

RESUMO

Bovine ephemeral fever virus (BEFV) is an economically important arbovirus affecting cattle and water buffalo. Currently, isolates can be separated into three phylogenetic groups, differentiated by the place of isolation, namely, East Asia, Australia, and the Middle East. BEFV surface glycoprotein (G) genes from 14 South African field strains collected between 1968 and 1999 were sequenced and compared to 154 published sequences. The BEFV isolates from South Africa were found to be phylogenetically distinct from those from other parts of the world.


Assuntos
Vírus da Febre Efêmera Bovina/classificação , Vírus da Febre Efêmera Bovina/isolamento & purificação , Febre Efêmera/virologia , Variação Genética , Glicoproteínas/genética , Filogenia , Proteínas Virais/genética , Animais , Bovinos , Vírus da Febre Efêmera Bovina/genética , África do Sul
19.
BMC Genomics ; 20(1): 368, 2019 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-31088349

RESUMO

BACKGROUND: Human papillomaviruses (HPVs) are genetically diverse, belonging to five distinct genera: Alpha, Beta, Gamma, Mu and Nu. All papillomaviruses have double stranded DNA genomes that are thought to evolve slowly because they co-opt high-fidelity host cellular DNA polymerases for their replication. Despite extensive efforts to catalogue all the HPV species that infect humans, it is likely that many still remain undiscovered. Here we use the sequences of ten novel Gammapapillomaviruses (Gamma-PVs) characterized in previous studies and related HPVs to analyse the evolutionary dynamics of these viruses at the whole genome and individual gene scales. RESULTS: We found statistically significant incongruences between the phylogenetic trees of different genes which imply gene-to-gene variation in the evolutionary processes underlying the diversification of Gamma-PVs. We were, however, only able to detect convincing evidence of a single recombination event which, on its own, cannot explain the observed incongruences between gene phylogenies. The divergence times of the last common ancestor (LCA) of the Alpha, Beta, Mu, Nu and Gamma genera was predicted to have existed between 49.7-58.5 million years ago, before splitting into the five main lineages. The LCA of the Gamma-PVs at this time was predicted to have existed between 45.3 and 67.5 million years ago: approximately at the time when the simian and tarsier lineages of the primates diverged. CONCLUSION: Consequently, we report here phylogenetic tree incongruence without strong evidence of recombination.


Assuntos
DNA Viral/análise , Gammapapillomavirus/classificação , Análise de Sequência de DNA/métodos , Animais , Evolução Molecular , Gammapapillomavirus/genética , Genoma Viral , Humanos , Filogenia , Recombinação Genética
20.
Sex Transm Infect ; 95(1): 5-12, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30018088

RESUMO

OBJECTIVES: Vaginal dysbiosis and STIs are important drivers of the HIV epidemic and reproductive complications. These conditions remain prevalent, partly because most cases are asymptomatic. We have shown that inflammatory cytokines interleukin (IL)-1α, IL-1ß and interferon-γ-induced protein (IP)-10 are biomarkers for detecting asymptomatic STIs and vaginal dysbiosis (bacterial vaginosis (BV) or intermediate microbiota). This study aimed to validate the performance of these biomarkers in African women recruited regardless of symptoms. METHODS: IL-1α, IL-1ß and IP-10 were measured in menstrual cup secretions, endocervical, lateral vaginal wall and vulvovaginal swabs from 550 women from Pretoria, Soweto and Cape Town, South Africa and Bondo, Kenya using Luminex and ELISA. STIs were assessed by PCR, BV by Nugent scoring and vaginal microbiota by 16S rRNA sequencing. RESULTS: Across four study populations and four types of genital specimens, the performance of IL-1α, IL-1ß and IP-10 for identification of women with STIs, BV or intermediate microbiota was consistent. Of the genital samples assessed, biomarkers measured in lateral vaginal wall swabs performed best, correctly classifying 76%(95% CI 70% to 81%) of women according to STI, BV or intermediate microbiota status (sensitivity 77%, specificity 71%) and were more accurate than clinical symptoms (sensitivity 41%, specificity 57%) (p=0.0003). Women incorrectly classified as STI/BV positive using the biomarkers had more abundant dysbiosis-associated bacteria, including Prevotella bivia and Gardnerella sp, detected by 16S rRNA sequencing, but not Nugent scoring. Including vaginal pH with the cytokine biomarkers improved the accuracy of the test (82% (95% CI 75% to 88%) correctly classified), although pH alone had poor specificity (61%). CONCLUSIONS: An inexpensive, point-of-care screening test including IL-1α, IL-1ß and IP-10 (and potentially pH) could be used in resource-limited settings to identify women with asymptomatic STIs and dysbiosis. These women could then be referred for aetiological testing, followed by specific treatment.


Assuntos
Infecções Assintomáticas , Quimiocina CXCL10/imunologia , Disbiose/imunologia , Interleucina-1alfa/imunologia , Interleucina-1beta/imunologia , Infecções Sexualmente Transmissíveis/imunologia , Vagina/imunologia , Vaginose Bacteriana/imunologia , Adolescente , Adulto , Doenças Assintomáticas , Biomarcadores , Secreções Corporais/química , Quimiocina CXCL10/metabolismo , Citocinas/imunologia , Citocinas/metabolismo , Disbiose/diagnóstico , Disbiose/metabolismo , Ensaio de Imunoadsorção Enzimática , Feminino , Gardnerella/genética , Humanos , Concentração de Íons de Hidrogênio , Inflamação , Interleucina-1alfa/metabolismo , Interleucina-1beta/metabolismo , Quênia , Programas de Rastreamento , Sistemas Automatizados de Assistência Junto ao Leito , Reação em Cadeia da Polimerase , Prevotella/genética , RNA Ribossômico 16S/análise , Infecções Sexualmente Transmissíveis/diagnóstico , Infecções Sexualmente Transmissíveis/metabolismo , África do Sul , Vagina/química , Vagina/metabolismo , Vagina/microbiologia , Vaginose Bacteriana/diagnóstico , Vaginose Bacteriana/metabolismo , Adulto Jovem
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