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1.
Arch Biochem Biophys ; 756: 109994, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38626818

RESUMO

Interactions between the plasma cells and the BM microenvironment of Multiple myeloma (MM) take place through factors such as exosomes. Many studies have confirmed the role of exosomes in these interactions. By carrying proteins, cytokines, lipids, microRNAs, etc. as their cargo, exosomes can regulate the interactions between MM plasma cells and neighboring cells and participate in the signaling between cancer cells and the environment. It has been shown that MM-derived exosomes can induce angiogenesis, enhance osteoblast activity, confer drug resistance, and have immunosuppressive properties. Abnormal cargos in endosomes originating from MM patients, can be used as a cancer biomarker to detect or screen early prognosis in MM patients. The native nanostructure of exosomes, in addition to their biocompatibility, stability, and safety, make them excellent candidates for therapeutic, drug delivery, and immunomodulatory applications against MM. On the other hand, exosomes derived from dendritic cells (DC) may be used as vaccines against MM. Thanks to the development of new 'omics' approaches, we anticipate to hear more about exosomes in fight against MM. In the present review, we described the most current knowledge on the role of exosomes in MM pathogenesis and their potential role as novel biomarkers and therapeutic tools in MM.


Assuntos
Exossomos , Mieloma Múltiplo , Exossomos/metabolismo , Mieloma Múltiplo/diagnóstico , Mieloma Múltiplo/terapia , Mieloma Múltiplo/patologia , Mieloma Múltiplo/tratamento farmacológico , Mieloma Múltiplo/metabolismo , Humanos , Biomarcadores Tumorais/metabolismo , Prognóstico , Microambiente Tumoral , Animais
2.
Cancers (Basel) ; 15(14)2023 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-37509382

RESUMO

Macrophages are types of immune cells, with ambivalent functions in tumor growth, which depend on the specific environment in which they reside. Tumor-associated macrophages (TAMs) are a diverse population of immunosuppressive myeloid cells that play significant roles in several malignancies. TAM infiltration in malignancies has been linked to a poor prognosis and limited response to treatments, including those using checkpoint inhibitors. Understanding the precise mechanisms through which macrophages contribute to tumor growth is an active area of research as targeting these cells may offer potential therapeutic approaches for cancer treatment. Numerous investigations have focused on anti-TAM-based methods that try to eliminate, rewire, or target the functional mediators released by these cells. Considering the importance of these strategies in the reversion of tumor resistance to conventional therapies and immune modulatory vaccination could be an appealing approach for the immunosuppressive targeting of myeloid cells in the tumor microenvironment (TME). The combination of reprogramming and TAM depletion is a special feature of this approach compared to other clinical strategies. Thus, the present review aims to comprehensively overview the pleiotropic activities of TAMs and their involvement in various stages of cancer development as a potent drug target, with a focus on hematologic tumors.

3.
Vaccines (Basel) ; 10(9)2022 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-36146527

RESUMO

Glioblastoma (GBM) is the most typical and aggressive form of primary brain tumor in adults, with a poor prognosis. Successful glioma treatment is hampered by ineffective medication distribution across the blood-brain barrier (BBB) and the emergence of drug resistance. Although a few FDA-approved multimodal treatments are available for glioblastoma, most patients still have poor prognoses. Targeting epigenetic variables, immunotherapy, gene therapy, and different vaccine- and peptide-based treatments are some innovative approaches to improve anti-glioma treatment efficacy. Following the identification of lymphatics in the central nervous system, immunotherapy offers a potential method with the potency to permeate the blood-brain barrier. This review will discuss the rationale, tactics, benefits, and drawbacks of current glioma therapy options in clinical and preclinical investigations.

4.
Cancer Cell Int ; 22(1): 262, 2022 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-35989351

RESUMO

Glioblastoma belongs to the most aggressive type of cancer with a low survival rate that is characterized by the ability in forming a highly immunosuppressive tumor microenvironment. Intercellular communication are created via exosomes in the tumor microenvironment through the transport of various biomolecules. They are primarily involved in tumor growth, differentiation, metastasis, and chemotherapy or radiation resistance. Recently several studies have highlighted the critical role of tumor-derived exosomes against immune cells. According to the structural and functional properties, exosomes could be essential instruments to gain a better molecular mechanism for tumor understanding. Additionally, they are qualified as diagnostic/prognostic markers and therapeutic tools for specific targeting of invasive tumor cells such as glioblastomas. Due to the strong dependency of exosome features on the original cells and their developmental status, it is essential to review their critical modulating molecules, clinical relevance to glioma, and associated signaling pathways. This review is a non-clinical study, as the possible role of exosomes and exosomal microRNAs in glioma cancer are reported. In addition, their content to overcome cancer resistance and their potential as diagnostic biomarkers are analyzed.

5.
J Trace Elem Med Biol ; 73: 127044, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35901669

RESUMO

COVID-19 is a rapidly spreading disease, which has caught the world by surprise. Millions of people suffer from illness, and the mortality rates are dramatically high. Currently, there is no specific and immediate treatment for this disease. Remedies are limited to supportive regiments and few antiviral and anti-inflammatory drugs. The lack of a definite cure for COVID-19 is the reason behind its high mortality and global prevalence. COVID-19 can lead to a critical illness with severe respiratory distress and cytokine release. Increased oxidative stress and excessive production of inflammatory cytokines are vital components of severe COVID-19. Micronutrients, metalloids, and vitamins such as iron, manganese, selenium, Zinc, Copper, vitamin A, B family, and C are among the essential and trace elements that play a pivotal role in human nutrition and health. They participate in metabolic processes that lead to energy production. In addition, they support immune functions and act as antioxidants. Therefore, maintaining an optimal level of micronutrients intake, particularly those with antioxidant activities, is essential to fight against oxidative stress, modulate inflammation, and boost the immune system. Therefore, these factors could play a crucial role in COVID-19 prevention and treatment. In this review, we aimed to summarize antiviral properties of different vitamins and minerals. Moreover, we will investigate the correlation between them and their effects in COVID-19 patients.


Assuntos
Tratamento Farmacológico da COVID-19 , Selênio , Antioxidantes/farmacologia , Antioxidantes/uso terapêutico , Antivirais , Suplementos Nutricionais , Humanos , Micronutrientes/farmacologia , Micronutrientes/uso terapêutico , Minerais/uso terapêutico , Selênio/uso terapêutico , Vitamina A , Vitaminas/farmacologia , Vitaminas/uso terapêutico
6.
Sci Rep ; 12(1): 10852, 2022 06 27.
Artigo em Inglês | MEDLINE | ID: mdl-35760825

RESUMO

The recent outbreak of COVID-19 has increased hospital admissions, which could elevate the risk of nosocomial infections, such as A. baumannii and P. aeruginosa infections. Although effective vaccines have been developed against SARS-CoV-2, no approved treatment option is still available against antimicrobial-resistant strains of A. baumannii and P. aeruginosa. In the current study, an all-in-one antigen was designed based on an innovative, state-of-the-art strategy. In this regard, experimentally validated linear epitopes of spike protein (SARS-CoV-2), OmpA (A. baumannii), and OprF (P. aeruginosa) were selected to be harbored by mature OmpA as a scaffold. The selected epitopes were used to replace the loops and turns of the barrel domain in OmpA; OprF311-341 replaced the most similar sequence within the OmpA, and three validated epitopes of OmpA were retained intact. The obtained antigen encompasses five antigenic peptides of spike protein, which are involved in SARS-CoV-2 pathogenicity. One of these epitopes, viz. QTQTNSPRRARSV could trigger antibodies preventing super-antigenic characteristics of spike and alleviating probable autoimmune responses. The designed antigen could raise antibodies neutralizing emerging variants of SARS-CoV-2 since at least two epitopes are consensus. In conclusion, the designed antigen is expected to raise protective antibodies against SARS-CoV-2, A. baumannii, and P. aeruginosa.


Assuntos
Infecções por Acinetobacter , Acinetobacter baumannii , COVID-19 , Acinetobacter baumannii/metabolismo , Epitopos , Humanos , Pseudomonas aeruginosa , SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus/metabolismo
7.
Int J Pept Res Ther ; 28(1): 33, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34931119

RESUMO

The structural consequences of ongoing mutations on the SARS-CoV-2 spike-protein remains to be fully elucidated. These mutations could change the binding affinity between the virus and its target cell. Moreover, obtaining new mutations would also change the therapeutic efficacy of the designed drug candidates. To evaluate these consequences, 3D structure of a mutant spike protein was predicted and checked for stability, cavity sites, and residue depth. The docking analyses were performed between the 3D model of the mutated spike protein and the ACE2 protein and an engineered therapeutic ACE2 against COVID-19. The obtained results revealed that the N501Y substitution has altered the interaction orientation, augmented the number of interface bonds, and increased the affinity against the ACE2. On the other hand, the P681H mutation contributed to the increased cavity size and relatively higher residue depth. The binding affinity between the engineered therapeutic ACE2 and the mutant spike was significantly higher with a distinguished binding orientation. It could be concluded that the mutant spike protein increased the affinity, preserved the location, changed the orientation, and altered the interface amino acids of its interaction with both the ACE2 and its therapeutic engineered version. The obtained results corroborate the more aggressive nature of mutated SARS-CoV-2 due to their higher binding affinity. Moreover, designed ACe2-baased therapeutics would be still highly effective against covid-19, which could be the result of conserved nature of cellular ACE2. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s10989-021-10346-1.

8.
Sci Rep ; 11(1): 23622, 2021 12 08.
Artigo em Inglês | MEDLINE | ID: mdl-34880279

RESUMO

Spike glycoprotein (Sgp) is liable for binding of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) to the host receptors. Since Sgp is the main target for vaccine and drug designing, elucidating its mutation pattern could help in this regard. This study is aimed at investigating the correspondence of specific residues to the SgpSARS-CoV-2 functionality by explorative interpretation of sequence alignments. Centrality analysis of the Sgp dissects the importance of these residues in the interaction network of the RBD-ACE2 (receptor-binding domain) complex and furin cleavage site. Correspondence of RBD to threonine500 and asparagine501 and furin cleavage site to glutamine675, glutamine677, threonine678, and alanine684 was observed; all residues are exactly located at the interaction interfaces. The harmonious location of residues dictates the RBD binding property and the flexibility, hydrophobicity, and accessibility of the furin cleavage site. These species-specific residues can be assumed as real targets of evolution, while other substitutions tend to support them. Moreover, all these residues are parts of experimentally identified epitopes. Therefore, their substitution may affect vaccine efficacy. Higher rate of RBD maintenance than furin cleavage site was predicted. The accumulation of substitutions reinforces the probability of the multi-host circulation of the virus and emphasizes the enduring evolutionary events.


Assuntos
SARS-CoV-2/metabolismo , Glicoproteína da Espícula de Coronavírus/genética , Sequência de Aminoácidos , Enzima de Conversão de Angiotensina 2/química , Enzima de Conversão de Angiotensina 2/metabolismo , Sítios de Ligação , COVID-19/patologia , COVID-19/virologia , Análise por Conglomerados , Humanos , Cadeias de Markov , Mutação , Ligação Proteica , Domínios Proteicos/genética , SARS-CoV-2/isolamento & purificação , Alinhamento de Sequência , Glicoproteína da Espícula de Coronavírus/química , Glicoproteína da Espícula de Coronavírus/metabolismo
9.
Iran J Microbiol ; 13(3): 337-344, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34540172

RESUMO

BACKGROUND AND OBJECTIVES: Avian respiratory disease complex (RDC) is one of the most detrimental economic diseases that affected different parts of the world. Various pathogens cause the disease, but the most significant viral pathogens include avian influenza virus (AIV), infectious bronchitis virus (IBV), and Newcastle disease virus (NDV) are the most prevalent. To detect these pathogens, various methods have been discovered in the last decades. Detection and characterization of viruses by metagenomics methods have improved our knowledge about the role of virome in the avian complex respiratory disease. MATERIALS AND METHODS: This research investigates the viral pathogen populations that mostly participate in emerging these diseases using the NGS method RNA-sequencing. In surveillance of ten broiler farms from different cities with respiratory symptoms, trachea samples were collected to determine the pathogenic virome causing the disease. RESULTS: In this metagenomics analysis, nine viral families were identified, comprising 72.82% of RNA viruses, 24.32% of RT viruses, and 2.86% of DNA viruses. RNA viruses had the highest contribution to the respiratory disease complex instead of disease, including paramyxoviridae, orthomyxoviridae, coronaviridae, and picornaviridae viruses. Other viruses from the RNA viruses and DNA virus families were also identified in addition to these results. CONCLUSION: This research suggests that studies of pathogenic viromes in different diseases can help monitor different diseases and predict their future occurrence.

10.
Crit Rev Oncol Hematol ; 166: 103477, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34534658

RESUMO

Cancer can be caused by various factors, including the malfunction of tumor suppressor genes and the hyper-activation of proto-oncogenes. Tumor-associated extrachromosomal circular DNA (eccDNA) has been shown to adversely affect human health and accelerate malignant actions. Whole-genome sequencing (WGS) on different cancer types suggested that the amplification of ecDNA has increased the oncogene copy number in various cancers. The unique structure and function of ecDNA, its profound significance in cancer, and its help in the comprehension of current cancer genome maps, renders it as a hotspot to explore the tumor pathogenesis and evolution. Illumination of the basic mechanisms of ecDNA may provide more insights into cancer therapeutics. Despite the recent advances, different features of ecDNA require further elucidation. In the present review, we primarily discussed the characteristics, biogenesis, genesis, and origin of ecDNA and later highlighted its functions in both tumorigenesis and therapeutic resistance of different cancers.


Assuntos
DNA Circular/genética , DNA de Neoplasias/genética , Neoplasias , Oncogenes , Carcinogênese , Humanos , Neoplasias/genética
11.
Front Mol Biosci ; 8: 669431, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33996914

RESUMO

Large contact surfaces of protein-protein interactions (PPIs) remain to be an ongoing issue in the discovery and design of small molecule modulators. Peptides are intrinsically capable of exploring larger surfaces, stable, and bioavailable, and therefore bear a high therapeutic value in the treatment of various diseases, including cancer, infectious diseases, and neurodegenerative diseases. Given these promising properties, a long way has been covered in the field of targeting PPIs via peptide design strategies. In silico tools have recently become an inevitable approach for the design and optimization of these interfering peptides. Various algorithms have been developed to scrutinize the PPI interfaces. Moreover, different databases and software tools have been created to predict the peptide structures and their interactions with target protein complexes. High-throughput screening of large peptide libraries against PPIs; "hotspot" identification; structure-based and off-structure approaches of peptide design; 3D peptide modeling; peptide optimization strategies like cyclization; and peptide binding energy evaluation are among the capabilities of in silico tools. In the present study, the most recent advances in the field of in silico approaches for the design of interfering peptides against PPIs will be reviewed. The future perspective of the field and its advantages and limitations will also be pinpointed.

12.
Gastroenterol Hepatol Bed Bench ; 14(Suppl1): S82-S86, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35154606

RESUMO

AIM: The present study implemented an RT-qPCR assay for the detection and quantification of human cosavirus in stool specimens from pediatric patients involved in acute gastroenteritis. BACKGROUND: Human cosavirus is a newly recognized virus that seems to be partly related to acute gastroenteritis in pediatric patients. However, the relationship between human cosavirus and diseases in humans is unclear. METHODS: From January 2018 to December 2019, a total of 160 stool samples were collected from pediatric patients presenting with acute gastroenteritis in a hospital in Karaj, Iran. After viral RNA extraction, RT-qPCR was performed to amplify the 5'UTR region of the human cosavirus genome and viral load was analyzed. RESULTS: The human cosavirus genomic RNA was detected in 4/160 (2.5%) stool samples tested. The maximum viral load was determined to be 4.6×106 copies/ml in one sample obtained from a 4-year-old patient. CONCLUSION: The human cosavirus as a new member of the Picornaviridae family was illustrated in fecal samples from pediatric patients with acute gastroenteritis in Iran. This is the first documentation of human cosavirus circulation in Iranian children.

13.
Autoimmunity ; 53(2): 102-113, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31809599

RESUMO

Coeliac disease (CD) is a chronic autoimmune disease that is characterized by malabsorption in sensitive individuals. CD is triggered by the ingestion of grains containing gluten. CD is concomitant with several other disorders, including dermatitis herpetiformis, selective IgA deficiency, thyroid disorders, diabetes mellitus, various connective tissue disorders, inflammatory bowel disease, and rheumatoid arthritis. The advent of high throughput technologies has provided a massive wealth of data which are processed in various omics scale fields. These approaches have revolutionized the medical research and monitoring of the biological systems. In this regard, omics scaled analyses of CD by Comparative Toxicogenomics Database (CTD), DISEASES, and GeneCards databases have retrieved 2656 CD associated genes. Amongst, 54 genes were assigned by Venn Diagram of the intersection to be shared by these 3 databases for CD. These common genes were subjected to further analysis and screening. The Enrich database, GeneMANIA, Cytoscape, and WebGestalt (WEB-based GEne SeT AnaLysis Toolkit) were employed for functional analysis. These analyses indicated that the obtained genes are mainly involved in the immune system and signalling pathways related to autoimmune diseases. The STAT1, ALB, IL10, IL2, IL4, IL17A, TGFB1, IL1B, IL6, TNF, IFNG hub genes were particularly indicated to have significant roles in CD. Functional analyses of these hub genes by GeneMANIA indicated that they are involved in immune systems regulation. Moreover, 25 out of 54 genes were identified to be seed genes by the WebGestalt database. Gene set analysis with GEO2R tool from Gene Expression Omnibus (GEO) showed that there were 15 significant genes in GSE76168, 29 significant genes in GSE87460, 12 significant genes in GSE87458, 9 significant genes in GSE87457, 3753 significant genes in GSE112102 and 1043 significant genes in GSE102991 with differential expression in coeliac patients compared to controls. The IRF1and STAT1 genes were common between the significant genes from GEO and the 54 CD related genes from three public databases. In the light these results, nine key genes, including IRF1, STAT1, IL17A, TGFB1, ALB, IL10, IL2, IL4, and IL1B, were identified to be associated with CD. These findings could be used to find novel diagnostic biomarkers, understand the pathology of disease, and devise more efficient treatments.


Assuntos
Doença Celíaca/genética , Regulação da Expressão Gênica/imunologia , Redes Reguladoras de Genes/imunologia , Biomarcadores/análise , Doença Celíaca/diagnóstico , Doença Celíaca/imunologia , Biologia Computacional , Bases de Dados Genéticas/estatística & dados numéricos , Conjuntos de Dados como Assunto , Perfilação da Expressão Gênica , Humanos , Transdução de Sinais/genética , Transdução de Sinais/imunologia
14.
Turk J Med Sci ; 49(1): 368-374, 2019 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-30761845

RESUMO

Background: Conventionalmethods of detecting Brucella spp. suffer from technical and biological complications. Besides, newly characterized species of the genus Brucella could be neglected by previously designed polymerase chain reaction (PCR) tests. Therefore, a more accurate PCR-based test seems to be imminently needed Materials and methods: Blood samples were collected from 39 patients diagnosed with brucellosis and 25 healthy controls. Multiple sequence alignments (MSA) were performed on 500 Omp2-related protein and gene sequences. Thereafter, specific primers were designed and synthesized for the regions with highest conservancy. The collected samples were assessed by PCR test. To overcome the cross-reactivity issue, PCR thermal program was optimized regarding annealing time and temperature. Results: The MSA results indicated that the N terminus region of the Omp2 protein (DNA 5' end) is associated with highest conservancy. Primers with highest specificity were designed and synthesized. A two-step PCR reaction was successfully designed and optimized. The desirable bands were observed in clinical samples with high accuracy. Conclusion: It should be pointed out that using a precisely designed primer pair would bring about early infection detection, more success to detect all natural variants and higher cost-to-efficacy ratio in comparison to other detection methods


Assuntos
Brucella/genética , DNA Bacteriano/análise , Tipagem Molecular/métodos , Reação em Cadeia da Polimerase/métodos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Brucelose/diagnóstico , Brucelose/microbiologia , Estudos de Casos e Controles , Criança , Pré-Escolar , Simulação por Computador , DNA Bacteriano/genética , Feminino , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Alinhamento de Sequência , Adulto Jovem
15.
Biotechnol Lett ; 40(11-12): 1459-1466, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30293139

RESUMO

CD37 is a member of tetra-spanning superfamily (characterized by their four transmembrane domains). It is one of the specific proteins for normal and malignant mature B cells. Anti CD37 monoclonal antibodies are reported to improve the overall survival in CLL. These therapeutics will increase the efficacy and reduce the toxicity in patients with both newly diagnosed and relapsed and refractory disease. Recent clinical trials have shown promising outcomes for these agents, administered both as monotherapy and in combination with standard chemotherapeutics. Long-term follow-up of combination regimens has even raised the question of whether the patients with CLL could be treated with intensive chemo-immunotherapy. In the present study, CD37 is introduced as an appealing target to treat B cell malignancies. The anti-CD37 antibodies as one of the most successful therapeutics against CD37 are introduced and the clinical outcomes of their exploitation are explained.


Assuntos
Imunoterapia , Leucemia de Células B/terapia , Linfoma não Hodgkin/terapia , Tetraspaninas/antagonistas & inibidores , Antígenos de Neoplasias , Humanos , Imunoglobulina G/uso terapêutico , Proteínas Recombinantes de Fusão/uso terapêutico
16.
Toxicon ; 127: 90-99, 2017 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-28089770

RESUMO

Epsilon toxin of the Clostridium perfringens garnered a lot of attention due to its potential for toxicity in humans, extreme potency for cytotoxicity in mice and lack of any approved therapeutics prescribed for human. However, the intricacies of the Epsilon toxin action mechanism are yet to be understood. In this regard, various in silico tools have been exploited to model and refine the 3D structure of the toxin and its two receptors. The receptor proteins were embedded into designed lipid membranes within an aqueous and ionized environment. Thereafter, the modeled structures subjected to series of consecutive molecular dynamics runs to achieve the most natural like coordination for each model. Ultimately, protein-protein interaction analyses were performed to understand the probable action mechanism. The obtained results successfully confirmed the accuracy of employed methods to achieve high quality models for the toxin and its receptors within their lipid bilayers. Molecular dynamics analyses lead the structures to a more native like coordination. Moreover, the results of previous empirical studies were confirmed, while new insights for action mechanisms including the detailed roles of Hepatitis A virus cellular receptor 1 (HAVCR1) and Myelin and lymphocyte protein (MAL) proteins were achieved. In light of previous and our observations, we suggested novel models which elucidated the existing interplay between potential players of Epsilon toxin action mechanism with detailed structural evidences. These models would pave the way to have more robust understanding of the Epsilon toxin biology, more precise vaccine construction and more successful drug (inhibitor) design.


Assuntos
Toxinas Bacterianas/química , Receptor Celular 1 do Vírus da Hepatite A/química , Proteínas Proteolipídicas Associadas a Linfócitos e Mielina/química , Bicamadas Lipídicas , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Conformação Proteica
17.
J Virol Methods ; 141(2): 181-7, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17218022

RESUMO

Beak and feather disease virus (BFDV) is a common avian circovirus infection of wild Psittaciformes and is a recognised threat to endangered psittacine species. Currently, there is a requirement to develop BFDV antigen for diagnostic purposes and since efforts to propagate BFDV in vitro have so far been unsuccessful the entire coding region of BFDV ORF C1 was expressed in Sf9 insect cells using a baculovirus expression system. The entire coding region of BFDV ORF C1, the presumptive capsid, was expressed in Sf9 insect cells using baculovirus expression system. Electron microscopic examination of negatively stained material demonstrated that the recombinant protein self-assembled to produce virus-like particles (VLPs) thus confirming that ORF C1 is likely to be the sole determinant for capsid construction in vivo. BFDV VLPs also possessed haemagglutinating activity which provides further evidence that self-assembled BFDV VLPs retain receptor mediated biological activity and that the determinants for BFDV haemagglutination activity rely solely on the capsid protein. The recombinant protein reacted with anti-BFDV sera from naturally immune parrots and cockatoo and from chickens experimentally inoculated with native BFDV in both Western blots and haemagglutination inhibition (HI) assay. BFDV VLPs were also a suitable replacement antigen for serological detection of BFDV antibody by HI.


Assuntos
Antígenos Virais/genética , Baculoviridae/metabolismo , Proteínas do Capsídeo/genética , Circovirus/química , Animais , Anticorpos Antivirais/sangue , Anticorpos Antivirais/imunologia , Antígenos Virais/biossíntese , Antígenos Virais/imunologia , Aves , Western Blotting/métodos , Capsídeo/fisiologia , Proteínas do Capsídeo/biossíntese , Proteínas do Capsídeo/imunologia , Linhagem Celular , Infecções por Circoviridae/sangue , Infecções por Circoviridae/diagnóstico , Infecções por Circoviridae/virologia , Circovirus/fisiologia , Testes de Inibição da Hemaglutinação/métodos , Hemaglutinação por Vírus , Soros Imunes/imunologia , Fases de Leitura Aberta , Proteínas Recombinantes/biossíntese , Montagem de Vírus
18.
J Gen Virol ; 86(Pt 11): 3039-3046, 2005 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16227226

RESUMO

Psittacine beak and feather disease (PBFD) is recognized as a threat for endangered psittacine birds in Australia, New Zealand and South Africa. Several diagnostic methods for the detection of beak and feather disease virus (BFDV) infection have been developed but there are few studies comparing the relative merits or sensitivity and specificity of each diagnostic test. In this report, the results of PCR, haemagglutination (HA) and haemagglutination inhibition (HI) testing of diagnostic samples collected from 679 samples from a range of psittacine bird species suspected of being infected with BFDV are summarized and compared. There was a strong agreement (kappa = 0.757; P<0.0001) between PCR and HA testing of feather samples and PCR-negative birds were 12.7 times more likely to have HI antibody than PCR-positive birds. False-positive HA results with titres up to 1:320 were identified in six feather samples that were PCR negative; the haemagglutination detected in these samples was not inhibited by anti-BFDV antisera and was removed by filtration through a 0.22 microm filter. Similarly, one false-negative PCR result was detected in a feather sample that had a high HA titre (>1:40,960) and four false-positive PCR results were detected in a batch of four feather samples. Of 143 birds that were feather PCR positive, only two had detectable HI antibody, and these birds were also feather HA negative, suggesting that they were developing immunity to recent infection. All birds with HI antibody were negative on feather HA testing. The assays confirmed BFDV infection in two endangered swift parrots (Lathamus discolor) and phylogenetic analysis of the sequence data generated from ORF V1 of these isolates provide further evidence of BFDV genotypes clustering in parallel with the Loriidae, Cacatuidae and Psittacidae.


Assuntos
Doenças das Aves/diagnóstico , Circovirus/classificação , Psittaciformes/microbiologia , Viroses/veterinária , Animais , Bico/patologia , Bico/virologia , Doenças das Aves/microbiologia , Infecções por Circoviridae/virologia , Circovirus/genética , Circovirus/isolamento & purificação , Plumas/virologia , Testes de Inibição da Hemaglutinação/veterinária , Testes de Hemaglutinação/veterinária , Dados de Sequência Molecular , Filogenia , Reação em Cadeia da Polimerase/métodos , Viroses/diagnóstico , Viroses/microbiologia
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