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1.
ESMO Open ; 8(5): 101628, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37713929

RESUMO

BACKGROUND: Testing for epidermal growth factor receptor (EGFR) mutations is an essential recommendation in guidelines for metastatic non-squamous non-small-cell lung cancer, and is considered mandatory in European countries. However, in practice, challenges are often faced when carrying out routine biomarker testing, including access to testing, inadequate tissue samples and long turnaround times (TATs). MATERIALS AND METHODS: To evaluate the real-world EGFR testing practices of European pathology laboratories, an online survey was set up and validated by the Pulmonary Pathology Working Group of the European Society of Pathology and distributed to 64 expert testing laboratories. The retrospective survey focussed on laboratory organisation and daily EGFR testing practice of pathologists and molecular biologists between 2018 and 2021. RESULTS: TATs varied greatly both between and within countries. These discrepancies may be partly due to reflex testing practices, as 20.8% of laboratories carried out EGFR testing only at the request of the clinician. Many laboratories across Europe still favour single-test sequencing as a primary method of EGFR mutation identification; 32.7% indicated that they only used targeted techniques and 45.1% used single-gene testing followed by next-generation sequencing (NGS), depending on the case. Reported testing rates were consistent over time with no significant decrease in the number of EGFR tests carried out in 2020, despite the increased pressure faced by testing facilities during the COVID-19 pandemic. ISO 15189 accreditation was reported by 42.0% of molecular biology laboratories for single-test sequencing, and by 42.3% for NGS. 92.5% of laboratories indicated they regularly participate in an external quality assessment scheme. CONCLUSIONS: These results highlight the strong heterogeneity of EGFR testing that still occurs within thoracic pathology and molecular biology laboratories across Europe. Even among expert testing facilities there is variability in testing capabilities, TAT, reflex testing practice and laboratory accreditation, stressing the need to harmonise reimbursement technologies and decision-making algorithms in Europe.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Humanos , Carcinoma Pulmonar de Células não Pequenas/diagnóstico , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Laboratórios , Estudos Retrospectivos , Pandemias , Mutação , Receptores ErbB/genética , Europa (Continente)
2.
Urolithiasis ; 48(5): 377-384, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32719990

RESUMO

Calcium oxalate (CaOx) crystal deposition within the tubules is often a perplexing finding on renal biopsy of both native and transplanted kidneys. Understanding the underlying causes may help diagnosis and future management. The most frequent cause of CaOx crystal deposition within the kidney is hyperoxaluria. When this is seen in native kidney biopsy, primary hyperoxaluria must be considered and investigated further with biochemical and genetic tests. Secondary hyperoxaluria, for example due to enteric hyperoxaluria following bariatric surgery, ingested ethylene glycol or vitamin C overdose may also cause CaOx deposition in native kidneys. CaOx deposition is a frequent finding in renal transplant biopsy, often as a consequence of acute tubular necrosis and is associated with poorer long-term graft outcomes. CaOx crystal deposition in the renal transplant may also be secondary to any of the causes associated with this phenotype in the native kidney. The pathophysiology underlying CaOx deposition is complex but this histological phenotype may indicate serious underlying pathology and should always warrant further investigation.


Assuntos
Oxalato de Cálcio/metabolismo , Hiperoxalúria/metabolismo , Rim/metabolismo , Humanos , Hiperoxalúria/complicações , Hiperoxalúria/diagnóstico , Hiperoxalúria/etiologia
3.
Urology ; 145: 38-51, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32640263

RESUMO

We performed a systematic review to look at the role of alternative or complementary medicine such as music, acupressure, acupuncture, transcutaneous electrical nerve stimulation (TENS) and audiovisual distractions to decrease analgesia requirement and alleviate anxiety during SWL. Twenty-three papers(2439 participants) were included: Music (n = 1056.6%), Acupuncture (n = 517.7%), Acupressure (n = 13.8%), TENS (n = 617.2%), and audiovisual distraction (n = 14.6%). Most of the studies showed that complementary therapy, lowered pain, and anxiety with higher patient satisfaction and willingness to undergo the procedure. With its feasibility and convenience, urological guidelines need to endorse it, and more should be done to promote its use in outpatient urological procedures.


Assuntos
Analgesia , Ansiedade/prevenção & controle , Terapias Complementares/métodos , Litotripsia/psicologia , Acupressão/estatística & dados numéricos , Terapia por Acupuntura/estatística & dados numéricos , Recursos Audiovisuais/estatística & dados numéricos , Terapias Complementares/estatística & dados numéricos , Humanos , Musicoterapia/estatística & dados numéricos , Dor Processual/prevenção & controle , Satisfação do Paciente , Ensaios Clínicos Controlados Aleatórios como Assunto , Estimulação Elétrica Nervosa Transcutânea/estatística & dados numéricos
4.
Gastroenterol Res Pract ; 2019: 1592306, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30881445

RESUMO

BACKGROUND: As the malignant potential of sessile serrated lesions/polyps (SSL/Ps) and traditional serrated adenomas (TSAs) has been clearly demonstrated, it is important that serrated polyps are identified and correctly classified histologically. AIM: Our aim was to characterize the clinicopathological features of a series of SSL/Ps & TSAs, to assess the accuracy of the pathological diagnosis, the incidence, and the rate of dysplasia in SSL/Ps & TSAs. METHODS: We identified all colorectal serrated polyps between 01/01/2004 and 31/05/2016, by searching the laboratory information system for all cases assigned a "serrated adenoma" SNOMED code. All available and suitable slides were reviewed by one pathologist, who was blinded to the original diagnosis and the site of the polyp. Subsequently discordant cases, SSL/Ps with dysplasia, and all TSAs were reviewed by a second pathologist. RESULTS: Over a 149-month period, 759 "serrated adenoma" polyps were identified, with 664 (from 523 patients) available for review. 41.1% were reviewed by both pathologists; 15.1% (100/664) were reclassified, with the majority being changed from SSL/P to hyperplastic polyp (HYP) (66/664; 9.9%). 80.3% of these HYPs were located in the left colon, and the majority exhibited prolapse effect. There were 520 SSL/Ps (92.2%) & 40 TSAs (7.1%). The majority of SSL/Ps were in the right colon (86.7%) and were small (64.5% <1 cm), while most TSAs were in the left colon (85.7%) and were large (73.1%≥1 cm). 6.7% of SSL/Ps exhibited dysplasia, the majority of which were large (66.7%≥1 cm). Following consensus review, 13/520 (2.5%) SSL/Ps were downgraded from SSL/P with dysplasia to SSL/P without dysplasia. Detection of SSL/Ps peaked in the most recent years reviewed (87.5% reported between 2013 and 2016, inclusive), coinciding with the introduction of "BowelScreen" (the Irish FIT-based colorectal cancer screening programme). CONCLUSIONS: Awareness of, and adherence to, diagnostic criteria is essential for accurate classification of colorectal polyps.

5.
BJS Open ; 2(6): 456-463, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30511046

RESUMO

BACKGROUND: Caudal-related homeobox transcription factor 2 (CDX2) is an intestine-specific transcription factor implicated in tumour differentiation, proliferation, cell adhesion and migration. Negative CDX2 status (CDX2-) is associated with worse prognosis in colorectal cancer and may identify high-risk stage II disease that benefits from adjuvant chemotherapy. This observational study investigated whether CDX2- is associated with prognosis or response to chemotherapy in the mismatch repair-deficient (dMMR) phenotype of colorectal cancer. METHODS: Patients with resectable dMMR colorectal cancer were eligible for inclusion. The prognostic and predictive value of CDX2 expression on the presence of lymph node metastasis (LNM) and survival was investigated. CDX2 status was determined via immunohistochemistry using the Leica Bond™ CDX2 (clone EP25) ready-to-use primary antibody. RESULTS: Some 235 of 238 consecutive dMMR tumours were assessed for CDX2 status. CDX2- was observed in 15·7 per cent of colorectal cancer. Interobserver agreement was excellent (κ = 0·863; P < 0·001). CDX2- was significantly associated with female sex, increased size, advanced stage, worse conventional and poorly differentiated cluster (PDC) grade, mucinous morphology, perineural and lymphovascular invasion, and pN status (all P ≤ 0·038). CDX2- was not associated with LNM or survival in multivariable analysis. Independent predictors of LNM were PDC grade (odds ratio (OR) 4·12, 95 per cent c.i. 1·76 to 9·63; P = 0·001) and extramural venous invasion (OR 3·79, 1·62 to 8·85; P = 0·002). Budding (hazard ratio (HR) 2·79, 95 per cent c.i. 1·60 to 4·87; P < 0·001), pT status (HR 3·59, 1·29 to 10·01; P = 0·015) and adjuvant chemotherapy (HR 2·07, 1·15 to 3·74; P = 0·016) were independently associated with worse disease-free survival. CONCLUSION: CDX2- does not confer a worse prognosis in the dMMR phenotype of colorectal cancer. The MMR status of patients with colorectal cancer should be determined before assessing CDX2 status.

6.
Eur J Surg Oncol ; 42(11): 1680-1686, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27370895

RESUMO

BACKGROUND: Up to 15% of colorectal cancers exhibit microsatellite instability (MSI), where errors in replication go unchecked due to defects in the mismatch repair system. This study aimed to determine survival in a large single-centre series of 1250 consecutive colorectal cancers subjected to universal MSI testing. METHODS: Clinical and pathological features of patients with colorectal cancer identified on prospectively maintained colorectal and pathology databases at St. Vincent's University Hospital from 2004 to May 2012 were examined. Mismatch repair (MMR) status was determined by immunohistochemistry. Kaplan-Meier curves, the log-rank test and Cox regression were used to associate survival with clinical and pathological characteristics. RESULTS: Of the 1250 colorectal cancers in the study period, 11% exhibited MSI (n = 138). Patients with MSI tumours had significantly lower rates of lymph node and distant metastases (MSI N+ rate: 24.8% compared with MSS N+ rate: 46.2%, p < 0.001). For Stage I and II disease MSI was associated with improved disease free survival (DSS) compared with MSS colon cancer. However, patients with Stage III MSI colon cancers had a worse DSS than those with MSS tumours. Stage III MSI tumours exhibited higher rates of lymphovascular invasion and perineural invasion than Stage I/II MSI tumours. CONCLUSION: MSI is associated with a reduced risk of nodal and distant metastases, with an improved DSS in Stage I/II colon cancer. However, when MSI tumours progress to Stage III these patients had worse outcomes and pathological features. New strategies for this cohort of patients may be required to improve outcomes.


Assuntos
Neoplasias do Colo/genética , Instabilidade de Microssatélites , Idoso , Idoso de 80 Anos ou mais , Neoplasias do Colo/diagnóstico , Neoplasias do Colo/mortalidade , Neoplasias do Colo/patologia , Reparo de Erro de Pareamento de DNA , Intervalo Livre de Doença , Feminino , Humanos , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias
7.
Br J Cancer ; 111(6): 1021-46, 2014 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-25117809

RESUMO

Cell-line misidentification and contamination with microorganisms, such as mycoplasma, together with instability, both genetic and phenotypic, are among the problems that continue to affect cell culture. Many of these problems are avoidable with the necessary foresight, and these Guidelines have been prepared to provide those new to the field and others engaged in teaching and instruction with the information necessary to increase their awareness of the problems and to enable them to deal with them effectively. The Guidelines cover areas such as development, acquisition, authentication, cryopreservation, transfer of cell lines between laboratories, microbial contamination, characterisation, instability and misidentification. Advice is also given on complying with current legal and ethical requirements when deriving cell lines from human and animal tissues, the selection and maintenance of equipment and how to deal with problems that may arise.


Assuntos
Pesquisa Biomédica/normas , Linhagem Celular/microbiologia , Equipamentos e Provisões/normas , Mycoplasma , Segurança/normas , Animais , Pesquisa Biomédica/ética , Linhagem Celular/classificação , Criopreservação/normas , Meios de Cultura/normas , Contaminação de Equipamentos/prevenção & controle , Instabilidade Genômica , Humanos , Mycoplasma/isolamento & purificação , Fenótipo , Controle de Qualidade , Manejo de Espécimes/métodos , Manejo de Espécimes/normas , Reino Unido
8.
Equine Vet J ; 38(3): 224-9, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16706276

RESUMO

REASONS FOR PERFORMING STUDY: A method of removing equine arteritis virus (EAV) from equine semen used for artificial insemination is urgently needed. Recent medical studies suggest that a double semen processing technique of density gradient centrifugation followed by a 'swim-up' can provide virus-free sperm preparations for assisted reproduction. OBJECTIVES: To investigate the use of the double semen processing technique to obtain virus-free sperm preparations from stallion semen containing EAV. METHODS: Aliquots of an ejaculate from an uninfected stallion were spiked with virus and processed by the double processing technique. The sperm preparations were tested by PCR for the presence of EAV. The procedure was repeated using an ejaculate from a known shedding stallion, testing processed and unprocessed aliquots by PCR and virus isolation. RESULTS: Virus-free sperm preparations were obtained using the double sperm processing technique. The 'swim-up' step is apparently required to ensure complete virus removal. CONCLUSIONS: The double semen processing technique is potentially a useful and simple tool for the removal of EAV from the semen of shedding stallions. POTENTIAL RELEVANCE: The inclusion of density gradient centrifugation and 'swim-up' in protocols for the processing of semen for artificial insemination could help prevent the transmission of viral diseases carried in semen, such as EAV.


Assuntos
Infecções por Arterivirus/veterinária , Equartevirus/isolamento & purificação , Doenças dos Cavalos/prevenção & controle , Sêmen/virologia , Manejo de Espécimes/veterinária , Animais , Infecções por Arterivirus/prevenção & controle , Infecções por Arterivirus/transmissão , Infecções por Arterivirus/virologia , Doenças dos Cavalos/transmissão , Doenças dos Cavalos/virologia , Cavalos , Inseminação Artificial/veterinária , Masculino , Reação em Cadeia da Polimerase/métodos , Reação em Cadeia da Polimerase/veterinária , RNA Viral/análise , Manejo de Espécimes/métodos , Eliminação de Partículas Virais
10.
Respir Med ; 99(2): 220-6, 2005 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15715190

RESUMO

INTRODUCTION: Older patients are the most prevalent age cohort requiring bronchoscopy. Prior sedation should be offered to improve patient comfort and operator technical ease. Older patients have increased sensitivity to centrally acting drugs increasing the procedural risk. This perceived risk may limit access to bronchoscopy in older patients. There have been no systematic prospective placebo-controlled studies in older patients. We compared a novel premedication regimen-oral temazepam plus nebulised Lignocaine (new treatment) to an established regimen of intravenous alfentanyl (control). METHODS: Consecutive patients 75 years and older referred for bronchoscopy were considered. Twenty-five patients were randomly assigned to each group. The primary outcome measure was the lowest oxygen saturation recorded from the administration of IV drugs and for 30 min post-bronchoscopy. RESULTS: The lowest mean oxygen saturation in the new treatment group was 92.2% (90.3-94.2) and in the control group 91.1% (89.2-93.1). This was not statistically different (P = 0.370). There were no adverse events. CONCLUSION: This is the largest prospective study to date on an older population undergoing bronchoscopy supporting previous retrospective findings regarding the safety of this procedure. Determined by oxygen saturations there is no difference in safety between premedication regimens comprising oral temazepam/nebulised lignocaine or intravenous alfentanyl.


Assuntos
Broncoscopia/métodos , Lidocaína/uso terapêutico , Pneumopatias/diagnóstico , Dor/prevenção & controle , Temazepam/uso terapêutico , Idoso , Idoso de 80 Anos ou mais , Método Duplo-Cego , Quimioterapia Combinada , Feminino , Humanos , Masculino , Satisfação do Paciente , Pré-Medicação/métodos , Estudos Prospectivos , Resultado do Tratamento
15.
Virology ; 285(2): 366-75, 2001 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-11437670

RESUMO

Human nectin-1 (HveC, Prr1), a member of the immunoglobulin superfamily and a receptor for the entry of herpes simplex viruses 1 and 2 (HSV-1, HSV-2), pseudorabies virus (PRV), and bovine herpesvirus 1 (BHV-1), binds to viral gD. For HSV-1, HSV-2, and PRV, the gD-binding region of nectin-1 has been localized to the N-terminal V-like domain. To determine whether the two C-like domains of nectin-1 influenced gD binding and entry activity, genes encoding chimeric proteins were constructed. Portions of nectin-1 were replaced with homologous regions from nectin-2 (HveB, Prr2), a related protein with ability to mediate the entry of PRV, HSV-2, and Rid mutants of HSV-1, but not HSV-1 or BHV-1. Also, one or more domains of nectin-1 were fused to the two membrane-proximal Ig domains of CD4, a protein with no herpesvirus entry or gD-binding activity. The chimeric proteins were expressed in Chinese hamster ovary cells, which normally lack alphaherpesvirus entry receptors, and detected on the cell surface by one or more anti-nectin-1 monoclonal antibodies. One chimeric protein (nectin-1 amino acids 1-124 fused to CD4) failed to bind to soluble forms of HSV-1, HSV-2, PRV, and BHV-1 gD and, as expected, also failed to mediate entry of the viruses from which these gDs were derived. The other chimeric receptors bound all forms of gD. Some mediated the entry of all the viruses tested but others mediated entry of some but not all the viruses. We conclude that binding of gD to the nectin-1 V domain is not sufficient for entry activity, that there are structural requirements for entry activity independent of gD binding, and that these requirements are different for the several alphaherpesviruses that can use nectin-1 as a receptor.


Assuntos
Moléculas de Adesão Celular/metabolismo , Imunoglobulinas/metabolismo , Receptores Virais/metabolismo , Proteínas do Envelope Viral/metabolismo , Proteínas Virais/metabolismo , Sequência de Aminoácidos , Animais , Células CHO , Bovinos , Moléculas de Adesão Celular/genética , Membrana Celular/metabolismo , Cricetinae , Expressão Gênica , Herpesvirus Bovino 1/metabolismo , Herpesvirus Bovino 1/fisiologia , Herpesvirus Humano 1/metabolismo , Herpesvirus Humano 1/fisiologia , Herpesvirus Suídeo 1/metabolismo , Herpesvirus Suídeo 1/fisiologia , Herpesvirus Humano 2/metabolismo , Herpesvirus Humano 2/fisiologia , Humanos , Imunoglobulinas/genética , Dados de Sequência Molecular , Nectinas , Plasmídeos , Conformação Proteica , Receptores Virais/genética , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo
16.
Gene ; 265(1-2): 185-94, 2001 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-11255021

RESUMO

The Tage4 gene (Tumor-Associated Glycoprotein E4) is a member of the immunoglobulin superfamily overexpressed in rat colon tumors and Min mouse intestinal adenomas. The Tage4 cDNA presents approximately 60% identity with the human CD155, a member of the immunoglobulin superfamily coding for a transmembrane protein capable of serving as an entry receptor for poliovirus, porcine pseudorabies virus and bovine herpesvirus 1. We determined the structure of the Tage4 gene. This gene covers approximately 15 kb and is composed of eight exons and seven introns. We also isolated approximately 2 kb of the 5' flanking region of the Tage4 gene and demonstrated the existence of closely clustered transcription start sites. No splicing variant was identified by RT-PCR indicating that the Tage4 gene is transcribed as a unique mRNA. Finally, the protein encoded by the Tage4 gene was tested for ability to mediate entry of several viruses. These structural and functional features of the rat Tage4 gene were compared to those of the human CD155 gene. The results indicated that the Tage4 gene is probably orthologous to the gene for CD155.


Assuntos
Genes/genética , Glicoproteínas/genética , Herpesviridae/metabolismo , Proteínas de Membrana , Regiões 3' não Traduzidas/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Células CHO , Cricetinae , DNA/química , DNA/genética , Éxons , Glicoproteínas/metabolismo , Herpesviridae/genética , Humanos , Íntrons , Dados de Sequência Molecular , Regiões Promotoras Genéticas/genética , RNA Mensageiro/genética , Ratos , Receptores Virais/genética , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Alinhamento de Sequência , Análise de Sequência de DNA , Homologia de Sequência de Aminoácidos , Homologia de Sequência do Ácido Nucleico , Células Tumorais Cultivadas , beta-Galactosidase/genética , beta-Galactosidase/metabolismo
17.
Virus Res ; 74(1-2): 39-45, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11226572

RESUMO

Two cell surface proteins (nectin-1/HveC and nectin-2/HveB) shown previously to serve as receptors for the entry of herpes simplex virus 1 (HSV-1) wild-type and/or mutant strains were found to serve also as receptors for HSV-1-induced cell fusion. Transfection with genomic DNA from a syncytial HSV-1 strain encoding wild-type gD resulted in fusion of Chinese hamster ovary (CHO) cells expressing nectin-1 but not of cells expressing nectin-2. In contrast, transfection with DNA from a related HSV-1 strain encoding the mutant Rid1 form of gD resulted in fusion of CHO cells expressing either receptor but not of control cells. These results are consistent with the ability of each receptor to mediate entry of viruses expressing wild-type or Rid1 gD and with results obtained previously with HVEM (HveA), a third HSV-l entry receptor. Undersulfation of GAGs in receptor-expressing cell lines predictably reduced susceptibility to HSV-l infection. In contrast, susceptibility to cell fusion mediated by HVEM or nectin-1 was not reduced. Undersulfation of GAGs partially inhibited cell fusion mediated by nectin-2. We conclude that HSV-1-induced cell fusion requires a gD-binding entry receptor, that ability of an HSV-1 strain to use HVEM, nectin-2 or nectin-1 for cell fusion depends on the allele of gD expressed and that GAGs may influence cell fusion, dependent on the gD-binding receptor used, but are less important for cell fusion mediated by HVEM, nectin-2 or nectin-l than for viral entry.


Assuntos
Moléculas de Adesão Celular/metabolismo , Fusão de Membrana , Receptores Virais/metabolismo , Simplexvirus/metabolismo , Proteínas do Envelope Viral/metabolismo , Proteínas Virais de Fusão/metabolismo , Animais , Células CHO , Moléculas de Adesão Celular/genética , Cricetinae , DNA Viral/efeitos dos fármacos , Glicosaminoglicanos/química , Glicosaminoglicanos/metabolismo , Mutação , Nectinas , Receptores Virais/genética , Simplexvirus/genética , Ésteres do Ácido Sulfúrico/química , Ésteres do Ácido Sulfúrico/metabolismo , Transfecção/métodos , Proteínas do Envelope Viral/genética , Proteínas Virais de Fusão/química
18.
Age Ageing ; 29(3): 261-3, 2000 May.
Artigo em Inglês | MEDLINE | ID: mdl-10855910

RESUMO

PRESENTATION: a previously fit 80-year-old woman presented with a 2-week history of spontaneous and extensive bruising affecting all four limbs. The severity was such that she required a transfusion of 8 units of blood. RESULTS OF INVESTIGATIONS: a markedly prolonged activated partial thromboplastin time which was only partially corrected with normal plasma; tests for lupus anticoagulant were negative. Factor VIII levels were reduced and the Bethesda assay indicated an acquired inhibitor to factor VIII. She was treated with a combination of intravenous immunoglobulin and immunosuppression. OUTCOME: the response to treatment was excellent, with a marked reduction in anti-factor VIII antibody levels and resolution of the bruising over the next few weeks.


Assuntos
Autoanticorpos/imunologia , Doenças Autoimunes/etiologia , Contusões/etiologia , Fator VIII/antagonistas & inibidores , Idoso , Idoso de 80 Anos ou mais , Doenças Autoimunes/imunologia , Doenças Autoimunes/terapia , Contusões/imunologia , Contusões/terapia , Fator VIII/imunologia , Feminino , Seguimentos , Humanos , Resultado do Tratamento
19.
Virology ; 268(1): 147-58, 2000 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-10683337

RESUMO

Several human and animal alphaherpesviruses can enter cells via human herpesvirus entry mediator C (HveC), a receptor for viral glycoprotein D (gD). In previous studies with cells expressing unknown entry mediators, cellular expression of alphaherpesvirus gD was shown to inhibit entry of the homologous virus and sometimes also of heterologous alphaherpesviruses. To investigate the mechanism of gD-mediated interference and the basis for cross-interference among alphaherpesviruses, HveC was expressed in cells as the sole entry mediator, in the presence or absence of one of the gDs encoded by herpes simplex virus type 1, pseudorabies virus, or bovine herpesvirus type 1. Cells expressing HveC alone were highly susceptible to entry of all three viruses, whereas cells coexpressing HveC and any one of the gDs were at least partially resistant to infection by each virus. Coexpression of gD with HveC did not cause reduced levels of cell-surface HveC but the HveC had reduced ability to bind to exogenous gD. Coimmunoprecipitation experiments revealed that HveC was complexed with gD in lysates of cells expressing both. Thus, cellular expression of gD can interfere with alphaherpesvirus entry by blocking ligand-binding sites of the gD receptor(s) used for entry and cross-interference can occur because different forms of alphaherpesvirus gD can compete for shared entry receptors.


Assuntos
Alphaherpesvirinae/genética , Alphaherpesvirinae/fisiologia , Receptores do Fator de Necrose Tumoral , Receptores Virais/metabolismo , Proteínas do Envelope Viral/metabolismo , Animais , Western Blotting , Células CHO , Cricetinae , Citometria de Fluxo , Imunofluorescência , Infecções por Herpesviridae/virologia , Humanos , Plasmídeos/genética , Testes de Precipitina , Membro 14 de Receptores do Fator de Necrose Tumoral , Transfecção , Proteínas do Envelope Viral/genética
20.
J Virol ; 73(10): 8127-37, 1999 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-10482562

RESUMO

The human herpesvirus entry mediator C (HveC/PRR1) is a member of the immunoglobulin family used as a cellular receptor by the alphaherpesviruses herpes simplex virus (HSV), pseudorabies virus, and bovine herpesvirus type 1. We previously demonstrated direct binding of the purified HveC ectodomain to purified HSV type 1 (HSV-1) and HSV-2 glycoprotein D (gD). Here, using a baculovirus expression system, we constructed and purified truncated forms of the receptor containing one [HveC(143t)], two [HveC(245t)], or all three immunoglobulin-like domains [HveC(346t)] of the extracellular region. All three constructs were equally able to compete with HveC(346t) for gD binding. The variable domain bound to virions and blocked HSV infection as well as HveC(346t). Thus, all of the binding to the receptor occurs within the first immunoglobulin-like domain, or V-domain, of HveC. These data confirm and extend those of Cocchi et al. (F. Cocchi, M. Lopez, L. Menotti, M. Aoubala, P. Dubreuil, and G. Campadelli-Fiume, Proc. Natl. Acad. Sci. USA 95:15700, 1998). Using biosensor analysis, we measured the affinity of binding of gD from HSV strains KOS and rid1 to two forms of HveC. Soluble gDs from the KOS strain of HSV-1 had the same affinity for HveC(346t) and HveC(143t). The mutant gD(rid1t) had an increased affinity for HveC(346t) and HveC(143t) due to a faster rate of complex formation. Interestingly, we found that HveC(346t) was a tetramer in solution, whereas HveC(143t) and HveC(245t) formed dimers, suggesting a role for the third immunoglobulin-like domain of HveC in oligomerization. In addition, the stoichiometry between gD and HveC appeared to be influenced by the level of HveC oligomerization.


Assuntos
Receptores do Fator de Necrose Tumoral , Receptores Virais/metabolismo , Simplexvirus/fisiologia , Proteínas do Envelope Viral/metabolismo , Animais , Bovinos , Linhagem Celular , Dimerização , Humanos , Imunoglobulinas , Ligação Proteica , Membro 14 de Receptores do Fator de Necrose Tumoral , Receptores Virais/química , Replicação Viral
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