RESUMO
Patient reported outcome measures (PROM) are considered a good method of measuring the results of treatment outcomes with the aim of improving the functional, cognitive and mental state of patients and the quality of life during and after treatment. The publication of these results serves the patient's interest in finding the best provider for a treatment. The existing interest of many service providers for the integration of electronic PROM into everyday clinical practice is often faced by barriers due to financial, personnel and technical factors. This must be eliminated in the interest of patient information in order to facilitate the rapid introduction of this patient-centered treatment outcome measurement into as many hospitals and specialist departments as possible.
Assuntos
Medidas de Resultados Relatados pelo Paciente , Hospitais , Humanos , Médicos , Qualidade de Vida , Resultado do TratamentoRESUMO
OBJECTIVES: To examine ductus venosus (DV) flow in fetuses with and those without a cardiac defect and to evaluate different phases of DV flow in addition to the standard assessment of DV pulsatility index for veins (PIV) and the a-wave. METHODS: This was a retrospective study of singleton pregnancies that underwent first-trimester ultrasound screening, which included DV flow assessment, at the University of Tübingen (between 2010 and 2017) or the University of Cologne (between 2013 and 2016). The study population comprised normal fetuses and fetuses with major cardiac defects at a ratio of 10:1. For each fetus, the following parameters of the DV waveform were evaluated: qualitative assessment of the a-wave, PIV measurement and ratios of flow velocities during the S-wave (S) or D-wave (D) and the a-wave (a) or v-wave (v). Reproducibility of DV-PIV and DV flow ratios was evaluated in 30 fetuses in which the DV flow was assessed twice. RESULTS: Our study population included 480 anatomically normal fetuses and 48 with a cardiac defect. Median fetal nuchal translucency (NT) in the normal and in the affected group was 1.9 mm and 2.6 mm, respectively. In five (1.0%) of the normal and 18 (37.5%) of the affected cases, fetal NT thickness was above the 99th centile. In the normal group, the DV a-wave was reversed in 15 (3.1%) cases and the DV-PIV was above the 95th centile in 25 (5.2%). In the cases with cardiac defects, the a-wave was reversed and the DV-PIV measurement was above the 95th centile in 26 (54.2%). The reproducibility of measurement of the ratios of DV flow velocities was similar to that of the DV-PIV. Most cardiac defects were associated with an abnormal a/S or a/D ratio. If the cut-off for these two ratios was set at the 5th centile of the normal distribution, the detection rate of fetal cardiac anomalies would be 62.5%. This compares favorably with the DV-PIV, which detects 26 (54.2%) of the affected fetuses for the same threshold. CONCLUSION: In the first trimester, the a/S ratio has the potential to detect approximately 60% of congenital cardiac defects for a false-positive rate of 5%. Copyright © 2018 ISUOG. Published by John Wiley & Sons Ltd.
Assuntos
Coração Fetal/diagnóstico por imagem , Cardiopatias Congênitas/diagnóstico por imagem , Medição da Translucência Nucal/estatística & dados numéricos , Análise de Onda de Pulso/estatística & dados numéricos , Adulto , Estudos de Casos e Controles , Reações Falso-Positivas , Feminino , Coração Fetal/fisiopatologia , Cardiopatias Congênitas/embriologia , Humanos , Gravidez , Primeiro Trimestre da Gravidez , Reprodutibilidade dos Testes , Estudos Retrospectivos , Veias Umbilicais/diagnóstico por imagem , Veias Umbilicais/embriologia , Veia Cava Inferior/diagnóstico por imagem , Veia Cava Inferior/embriologiaRESUMO
Pluripotent hematopoietic stem cells (HSC) are critical in sustaining and constantly renewing the blood and immune system. The ability to alter biological characteristics of HSC by introducing and expressing genes would have enormous therapeutic possibilities. Previous unpublished work suggested that human HSC co-express CD34 (cluster of differentiation 34; an HSC marker) and CD155 (poliovirus receptor; also called Necl-5/Tage4/PVR/CD155). In the present study, we demonstrate the co-expression of CD34 and CD155 in primary human HSC. In addition, we demonstrate that poliovirus infects and replicates in human hematopoietic progenitor cell lines. Finally, we show that poliovirus replicates in CD34+ enriched primary HSC. CD34+ enriched HSC co-express CD155 and support poliovirus replication. These data may help further understanding of poliovirus spread in vivo and also demonstrate that human HSC may be amenable for gene therapy via poliovirus-capsid-based vectors. They may also help elucidate the normal function of Necl-5/Tage4/PVR/CD155.
Assuntos
Antígenos CD34/metabolismo , Células-Tronco Hematopoéticas/metabolismo , Células-Tronco Hematopoéticas/virologia , Poliovirus/fisiologia , Replicação Viral , Células da Medula Óssea/metabolismo , Células da Medula Óssea/virologia , Linhagem Celular , Células Cultivadas , HumanosRESUMO
Human campylobacteriosis, an infection caused by the bacterium Campylobacter, is a major issue in the United States food system, especially for poultry products. According to the Center for Disease Control, campylobacterosis is estimated to affect over 2.4 million people annually. Campylobacter jejuni and Campylobacter coli are 2 species responsible for the majority of campylobacterosis infections. Phenotypic and genotypic typing methods are often used to discriminate between bacteria at the species and subspecies level and are often used to identify pathogenic organisms, such as C. jejuni and C. coli. This review describes the design as well as advantages and disadvantages for 3 current phenotypic techniques (biotyping, serotyping, and multilocus enzyme electrophoresis) and 6 genotypic techniques (multilocus sequence typing, PCR, pulse-field gel electrophoresis, ribotyping, flagellin typing, and amplified fragment length polymorphisms) for typing pathogenic Campylobacter spp.
Assuntos
Técnicas de Tipagem Bacteriana/métodos , Infecções por Campylobacter/veterinária , Campylobacter coli/classificação , Campylobacter jejuni/classificação , Doenças das Aves Domésticas/microbiologia , Animais , Infecções por Campylobacter/epidemiologia , Infecções por Campylobacter/microbiologia , Campylobacter coli/isolamento & purificação , Campylobacter jejuni/isolamento & purificação , Galinhas , Fenótipo , Doenças das Aves Domésticas/epidemiologia , Reprodutibilidade dos TestesRESUMO
Campylobacter spp. require a microaerophilic environment (80% N(2), 10% CO(2), 5% H(2), and 5% O(2)) for growth. Since the late 1800s, several systems for creating and maintaining specific microbial atmospheres have been developed and applied. The objective of this study was to evaluate Campylobacter jejuni growth by means of 3 commonly used gas-delivery systems for generating a microaerophilic environment: automated, gas-generating sachet, and plastic storage bag. Pure culture C. jejuni cells were suspended in Brucella broth and spread onto campy cefex agar plates. For the automated gas-delivery system, plates were positioned in a Mart anaerobic jar and flushed with a microaerophilic gas mixture using an Anoxomat Mart II system (Mart Microbiology B. V., Netherlands). For the sachet samples, plates were placed in a Mart anaerobic jar and 3 Gaspak EZ campy sachets (Becton Dickinson and Company, Franklin Lakes, NJ) were activated to induce a microaerophilic gas environment. The plates placed in plastic storage bags were flushed with a microaerophilic gas mixture from a premixed tank. For all 3 systems, plates were placed in a low-temperature incubator at 42°C for 24 h. After 24 h, plates were removed from the incubator and colonies were counted. The entire experiment was repeated 5 times. Results indicated no significant difference in colony counts among the gas-delivery systems tested, but colonies grown under the sachet-generated environment were smaller than colonies in the other 2 methods. Smaller colonies could have resulted from the type of media used or the length of time the plates were incubated. In conclusion, all 3 gas-delivery methods were able to produce similar Campylobacter growth results. Initial and long-term costs of equipment, as well as laboratory space availability, may be influential when choosing a gas-delivery method for generating a microaerophilic environment.
Assuntos
Técnicas Bacteriológicas/métodos , Campylobacter jejuni/crescimento & desenvolvimento , Gases/administração & dosagem , Dióxido de Carbono/administração & dosagem , Hidrogênio/administração & dosagem , Nitrogênio/administração & dosagem , Oxigênio/administração & dosagemRESUMO
Recently, codling moth (CM, Cydia pomonella L.) populations with a significantly reduced susceptibility to C. pomonella granulovirus (CpGV) products have been observed in Germany. A novel CpGV isolate, designated CpGV-I12, is able to overcome the CpGV resistance. CpGV-I12 originated from Iran and showed superior efficacy in laboratory bioassays against a resistant CM strain (CpR), which has a 100-fold reduced susceptibility to commercially used isolate CpGV-M. Determination of the median lethal concentration (LC(50)) indicated that CpGV-I12 is nearly as efficient in resistant CpR as CpGV-M in a susceptible CM strain (CpS). Beyond, CpGV-I12 caused superior mortality in CpS. Infection experiments showed that the resistance breaking effect can be observed in all instars of CpR. CpGV-I12 is a promising alternative control agent of CM in orchards where conventional CpGV products fail. In addition, we demonstrate in bioassays with recombinant expressed Cry1Ab that cross-resistance to CpGV and Bacillus thuringiensis products is not likely.
Assuntos
Granulovirus/genética , Imunidade Inata/genética , Resistência a Inseticidas/genética , Mariposas/imunologia , Controle Biológico de Vetores , Animais , Reações Cruzadas , DNA Viral/análise , Relação Dose-Resposta Imunológica , Predisposição Genética para Doença , Granulovirus/patogenicidade , Interações Hospedeiro-Patógeno , Concentração Inibidora 50 , Larva/genética , Larva/imunologia , Larva/virologia , Longevidade/imunologia , Mariposas/genética , Mariposas/virologia , Mapeamento por RestriçãoRESUMO
Insect-specific baculoviruses are increasingly used as biological control agents of lepidopteran pests in agriculture and forestry, and they have been previously regarded as robust to resistance development by the insects. However, in more than a dozen cases of field resistance of the codling moth Cydia pomonella to commercially applied C. pomonella granulovirus (CpGV) in German orchards, resistance ratios exceed 1000. The rapid emergence of resistance is facilitated by sex-linkage and concentration-dependent dominance of the major resistance gene and genetic uniformity of the virus. When the gene is fixed, resistance levels approach 100,000-fold. Our findings highlight the need for development of resistance management strategies for baculoviruses.
Assuntos
Granulovirus/fisiologia , Padrões de Herança , Mariposas/genética , Mariposas/virologia , Controle Biológico de Vetores , Cromossomos Sexuais/genética , Animais , Bioensaio , Cruzamentos Genéticos , Feminino , Genes Dominantes , Genes de Insetos , Genes Virais , Ligação Genética , Granulovirus/genética , Masculino , Seleção GenéticaRESUMO
Neurofibromatosis type 1 is the most common of the phakomatoses and the clinical follow-up is an interdisciplinary challenge. The data of 27 patients with NF1 were systematically reviewed and compared to data from the literature. All of our patients had clinical signs of NF1. Besides the classic criteria café-au-lait spots (100%), freckling (48,1%), positive family history (44,1%), neurofibromas (40,7%), Lisch nodules (22,2%) and optic pathway tumors (22,2%) there were developmental delay (40,7%), macrocephaly (33,3%), strabism (29,6%), scoliosis (18,5%), epilepsy (14,8%), pubertal anomalies (14,8%), short stature (11,1%) and tics. Morphologically, CNS hamartomas (55,5%), astrocytomas (22,2%) and one pheochromocytoma became apparent. Special findings consist of one aneurysm of internal carotic arteria, juvenile xanthogranulomas, a case of pulmonary stenosis and an intracardial tumor. Four new mutations in the NF1 gene were found. Regular screening of optic glioma with MRI had no clinical significance. In contrast to other authors, one of our patients with optic glioma showed clinical progress after twelve years of age. The detection of astrocytomas led only to therapeutic consequences, when clinical signs or symptoms occurred. As with other authors, we found no potential for CNS hamartoma to proliferate. In three cases with pubertal anomalies we found CNS gliomas, which indicates the need for MRI. The expense of screening, apart from clinical surveillance, seems inadequate in relation to clinical relevance and costs. We describe four new mutations in the NF1 gene; there have been no specific genotype-phenotype correlations. Neurofibromatosis type 1 and associated clinical abnormalities in 27 children.
Assuntos
Neurofibromatose 1/complicações , Neurofibromatose 1/diagnóstico , Adolescente , Fatores Etários , Astrocitoma/diagnóstico , Astrocitoma/etiologia , Neoplasias Encefálicas/diagnóstico , Neoplasias Encefálicas/etiologia , Doenças Cardiovasculares/etiologia , Criança , Pré-Escolar , Diagnóstico Diferencial , Feminino , Genes da Neurofibromatose 1 , Genótipo , Hamartoma/diagnóstico , Hamartoma/etiologia , Humanos , Lactente , Imageamento por Ressonância Magnética , Masculino , Mutação , Neurofibromatose 1/genética , Glioma do Nervo Óptico/diagnóstico , Glioma do Nervo Óptico/etiologia , Fenótipo , Lobo Temporal , Xantogranuloma Juvenil/diagnóstico , Xantogranuloma Juvenil/etiologiaRESUMO
Specific cell-surface binding is the essential first step for cellular invasion by viruses. To understand this process, various methods to evaluate binding properties of viruses to cells have been developed. However, many rely on radioactive labeling or indirect immunofluorescence. The development of a novel fluorescence binding assay for poliovirus is described. Poliovirus (type 1 Mahoney or Sabin) was labeled directly with fluorescein using a commercially available fluoresceination kit. Fluorescently labeled poliovirus was bound to its specific receptor on Hela or U937 cells and detected by flow cytometric analysis. Specific binding and infectivity was retained, although reduced, depending on the extent of fluoresceination. Therefore, depending on the users' requirements, the extent of fluoresceination must be titrated carefully to achieve maximal fluorescence and minimal functional destruction. It is likely that this method may be useful with other viruses.
Assuntos
Citometria de Fluxo/métodos , Poliovirus/fisiologia , Corantes Fluorescentes/metabolismo , Células HeLa/virologia , Humanos , Poliomielite/virologia , Poliovirus/metabolismo , Coloração e Rotulagem , Células U937/virologia , Replicação ViralRESUMO
Radiation damage of self-assembled monolayers, which are prototypes of thin organic layers and highly organized biological systems, shows a strong dependence on temperature. Two limiting cases could be identified. Reactions involving transport of single atoms and small fragments proceed nearly independent of temperature. Reactions requiring transport of heavy fragments are, however, efficiently quenched by cooling. We foresee the combined use of temperature and irradiation by electrons or photons for advanced tailoring of self-assembled monolayers on surfaces. In addition, our results have direct implications for cryogenic approaches in advanced electron and x-ray microscopy and spectroscopy of biological macromolecules and cells.
Assuntos
Substâncias Macromoleculares/efeitos da radiação , Polímeros/efeitos da radiação , Materiais Biomiméticos/química , Materiais Biomiméticos/efeitos da radiação , Temperatura Baixa , Ouro/química , Substâncias Macromoleculares/química , Lipídeos de Membrana/química , Lipídeos de Membrana/efeitos da radiação , Polímeros/química , Compostos de Sulfidrila/química , TemperaturaRESUMO
First measurements with a prototype ionization chamber are described to be applied in online monitoring of modulated fields in radiation therapy. The liquids isooctane, isononane (TMP) and tetramethylsilane (TMS) are used in a high purity grade in order to realize high current signals for electronic read-out in parallel at frequencies exceeding 10 Hz. Signals of more than a factor 4 with respect to isooctane, analysis grade, are obtained. With an electrode structure of 400 pads, a uniformity in efficiency within 1.2% has been measured. The penumbra of a multileaf collimator could be resolved. Theoretical examination verifies that the free electrons in the liquids cause higher signals when the measured currents are compared with expectation for ion transport only.
Assuntos
Análise de Falha de Equipamento/métodos , Octanos/efeitos da radiação , Pentanos/efeitos da radiação , Proteção Radiológica/instrumentação , Radiometria/instrumentação , Radioterapia Conformacional/instrumentação , Silanos/efeitos da radiação , Transdutores , Simulação por Computador , Desenho de Equipamento , Estudos de Viabilidade , Modelos Teóricos , Sistemas On-Line/instrumentação , Projetos Piloto , Proteção Radiológica/métodos , Radiometria/métodos , Dosagem Radioterapêutica , Radioterapia Conformacional/métodos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Soluções/efeitos da radiação , Compostos de TrimetilsililRESUMO
Despite identification of the poliovirus (PV) receptor (CD155), mechanisms by which this molecule mediates paralytic disease remain obscure. Unanswered questions include CD155 localization in human tissues, the nature of cells supporting the first round of replication, identity of nonneural replication sites, and route of entry into the CNS. In earlier work, we showed that CD155 is expressed on primary human monocytes and that these cells support low, but statistically significant, levels of PV replication ex vivo without prior culturing. We hypothesize that monocytes support PV replication in vivo and that they contribute to pathogenesis. In the current study, we tested whether CD155-transgenic mouse hematopoietic cells express cell surface CD155 and whether these cells support PV replication. We found that the majority of monocyte/macrophages from peritoneal washes express CD155. In addition, 26-32% of CD155-transgenic bone marrow and spleen cells express CD155 on monocyte/macrophages, T cells and hematopoietic precursor cells. Various tissues supported PV replication without pre-culturing, however, pre-culturing or pre-treatment of mice with thioglycollate increased virus yield. These results are consistent with those from human cells and suggest that the CD155 transgenic mouse model is useful to help understand the role of hematopoietic cells in PV pathogenesis.
Assuntos
Células-Tronco Hematopoéticas/metabolismo , Proteínas de Membrana , Poliovirus/fisiologia , Receptores Virais/metabolismo , Animais , Líquido Ascítico/imunologia , Células da Medula Óssea/metabolismo , Células Cultivadas , Citometria de Fluxo , Células-Tronco Hematopoéticas/efeitos dos fármacos , Células-Tronco Hematopoéticas/virologia , Macrófagos/metabolismo , Camundongos , Camundongos Transgênicos , Monócitos/metabolismo , Receptores Virais/análise , Receptores Virais/genética , Baço/citologia , Baço/metabolismo , Linfócitos T/metabolismo , Tioglicolatos/farmacologia , Replicação Viral/efeitos dos fármacosRESUMO
BACKGROUND: As a potential angiogenetic factor the 14.1 kDa polypeptide angiogenin induces neovascularisation. MATERIALS AND METHODS: We investigated the angiogenin expression by immunoblotting and an ELISA in 60 tissue specimens (40 gliomas, 20 other intracranial tumours), in 22 glioma cell cultures and in 4 supernantants of cultivated glioblastoma cells. RESULTS: We could show that angiogenin is detectable in different kinds of intracranial tumours with the highest amount in meningiomas and the lowest amount in low grade astrocytomas. In tissue specimens, a significantly higher angiogenin expression was measured in meningiomas compared to gliomas and metastases. Angiogenin could be detected in primary cultivated glioma cells, but not in the permanent cell lines. There was a significant correlation to the malignancy within the gliomas with an increase of angiogenin concentration according to the higher grade of malignancy. CONCLUSIONS: Our data suggest that angiogenin may contribute to the malignant transformation of gliomas and could perhaps advise that the physiological role of angiogenin is not restricted exclusively to angiogenesis. Based on these findings the clinical importance of angiogenin for therapeutic decisions in malignant brain tumours remains unclear and further analyses on m-RNA-levels are required.
Assuntos
Neoplasias Encefálicas/metabolismo , Glioma/metabolismo , Ribonuclease Pancreático/biossíntese , Ensaio de Imunoadsorção Enzimática , Humanos , Modelos Moleculares , Células Tumorais CultivadasRESUMO
The "cysteine string protein" (CSP) genes of higher eukaryotes code for a novel family of proteins characterized by a "J" domain and an unusual cysteine-rich region. Previous studies had localized the proteins in neuropil and synaptic terminals of larval and adult Drosophila and linked the temperature-sensitive paralysis of the mutants described here to conditional failure of synaptic transmission. We now use the null mutants as negative controls in order to reliably detect even low concentrations of CSPs by immunohistochemistry, employing three monoclonal antibodies. In wild-type flies high levels of cysteine string proteins are found not only in apparently all synaptic terminals of the embryonic, larval, and adult nervous systems, but also in the "tall cells" of the cardia, in the follicle cells of the ovary, in specific structures of the female spermatheca, and in the male testis and ejaculatory bulb. In addition, low levels of CSPs appear to be present in all tissues examined, including neuronal perikarya, axons, muscles, Malpighian tubules, and salivary glands. Western blots of isolated tissues demonstrate that of the four isoforms expressed in heads only the largest is found in non-neural organs. The wide expression of CSPs suggests that at least some of the various phenotypes of the null mutants observed at permissive temperatures, such as delayed development, short adult lifespan, modified electroretinogram, and optomotor behavior, may be caused by the lack of CSPs outside synaptic terminals.
Assuntos
Drosophila melanogaster/genética , Proteínas de Insetos/genética , Proteínas de Membrana/genética , Fatores Etários , Animais , Western Blotting , Chaperoninas/química , Chaperoninas/genética , Clonagem Molecular , Eletrorretinografia , Exocitose/fisiologia , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Proteínas de Choque Térmico HSP40 , Proteínas de Insetos/química , Larva/química , Larva/fisiologia , Masculino , Proteínas de Membrana/análise , Dados de Sequência Molecular , Mutagênese Sítio-Dirigida/fisiologia , Proteínas do Tecido Nervoso/análise , Proteínas do Tecido Nervoso/genética , Sistema Nervoso/química , Sistema Nervoso/crescimento & desenvolvimento , Fenótipo , Terminações Pré-Sinápticas/química , Análise de Sequência de DNA , Homologia de Sequência de Aminoácidos , TemperaturaRESUMO
Using near-infrared spectroscopy, we investigated the time-course of the concentrations of oxygenated haemoglobin, [oxy-Hb], and deoxygenated haemoglobin [deoxy-Hb], in the occipital cortex of healthy human adults during standard sustained visual stimulation. Within a few seconds after stimulation (by coloured dodecahedron), we observed a decrease in [deoxy-Hb], peaking after 13 s ('initial undershoot'). In the subsequent 1-2 min, in seven out of ten subjects, [deoxy-Hb] gradually returned to a plateau closer to the baseline level. After cessation of stimulation, there was a 'post-stimulus overshoot' in [deoxy-Hb]. There was a statistically significant correlation between the size of the 'initial undershoot' and the post-stimulus overshoot'. The concentration of oxyhaemoglobin increased upon functional activation. However, in the mean across all subjects there was no 'initial overshoot'. After approximately 19 s it reached a plateau and remained constantly elevated throughout the activation period. After cessation of activation there was a 'post-stimulus undershoot' of oxyhaemoglobin. It is important to consider the time-course of haemoglobin oxygenation when interpreting functional activation data, especially those data obtained with oxygenation-sensitive methods, such as BOLD-contrast fMRI.
Assuntos
Percepção de Cores , Hemoglobinas/metabolismo , Lobo Occipital/irrigação sanguínea , Lobo Occipital/metabolismo , Oxiemoglobinas/metabolismo , Estimulação Luminosa , Adulto , Feminino , Humanos , Cinética , Masculino , Análise de Regressão , Espectrofotometria Infravermelho/métodosRESUMO
Regulation of CD44-mediated binding to hyaluronan is critical in normal and diseased immune cell function. In earlier work by others (Shepley and Racaniello, J. Virol., 68, 1301 1309), anti-CD44 mAb blocked poliovirus binding to CD155 (the poliovirus receptor) in HeLa cells, suggesting that CD155 and CD44 may be physically associated. Here, we present evidence that CD155 and CD44 are physically associated in human monocytes. In co-modulation experiments in U937 monocytic cells, CD155 and CD44 reciprocally co-modulated. In primary human monocytes, CD 155 syn-capped with CD44. In immunofluorescence flow cytometric experiments, anti CD44 mAb inhibited up to 94% of binding by anti-CD155 mAb which blocks poliovirus binding to CD155. This inhibition was specific for CD155. Culturing monocytes increased the extent of inhibition. In addition, mAb against PRR2, a novel molecule that is related to CD 155, was inhibited by anti-CD44 in a dose-dependent manner, but not by anti-CD14. These data support the interpretation that CD155 (and related proteins) are physically associated with CD44 on monocyte cell surfaces. Although the current study does not address functional significance, we speculate that this interaction may have a role in regulating monocyte CD44 ligand binding which may be critical in pathological processes such as tumor metastasis and arthritis.
Assuntos
Receptores de Hialuronatos/química , Proteínas de Membrana , Monócitos/imunologia , Agregação de Receptores , Receptores Virais/química , Anticorpos/imunologia , Linhagem Celular , Citometria de Fluxo , Imunofluorescência , Humanos , Receptores de Hialuronatos/imunologia , Ligantes , Receptores Virais/imunologiaRESUMO
Although poliovirus receptor is required to mediate poliovirus infection, its role in mediating the tissue specificity of poliovirus replication in natural infections remains unclear due to the presence of this receptor in nonsusceptible cells. It has been hypothesized that CD44 has a role in determining the susceptibility of cell to poliovirus. To test this hypothesis, we determined whether HepG2, a cultured cell line that lacks cell surface CD44, can support poliovirus replication. We found that PV(1) Mahoney, PV(2)W2, and PV(3)Leon strains of poliovirus can replicate in HepG2 cells. Jurkat cells, which also lack CD44, support PV replication. These results suggest that CD44 is not required for poliovirus replication in cultured cells. To examine this question further expression of CD44 in primary human monocytes was examined. Greater than 90% of monocytes express the poliovirus receptor but only 6% of these cells are susceptible to poliovirus infection, making this a good system to study blocks to poliovirus replication. 97% of primary human monocytes reacted with a monoclonal antibody against CD44 that has been shown to block poliovirus binding and replication. This finding suggests that CD44 is present on more cells that poliovirus infects, making CD44 unlikely to be the factor limiting poliovirus replication in human tissues.
Assuntos
Receptores de Hialuronatos/fisiologia , Poliovirus/fisiologia , Replicação Viral , Células HeLa , Humanos , Células Jurkat , Monócitos/citologia , Monócitos/virologia , Células Tumorais CultivadasRESUMO
Poliovirus (PV) is not often described as a monocyte- or macrophage-tropic virus; however, previous work indicated that neurovirulent PV type 1 Mahoney [PV(1)Mahoney] can productively infect primary human monocytes. To determine whether this replication has a functional role in pathogenesis, primary human mononuclear blood cells were infected with pairs of attenuated and neurovirulent strains of PV. Two neurovirulent strains of PV, PV(1)Mahoney and PV(2)MEF-1, replicated faster and to higher titers than attenuated counterparts PV(1)Sabin and PV(2)W-2, respectively, in primary human monocytes, suggesting that this replication may contribute to pathogenesis. PV(3)Leon grew weakly, while PV(3)Sabin, PV(2)Sabin, and PV(2) P712 did not replicate in these cells, perhaps because of their slow replication cycle. In U937 cells, a monocytelike cell line, PV(1)Mahoney replicated but PV(1)Sabin did not, while both grew well in HeLa cells. When molecular recombinants of PV(1)Mahoney and PV(1)Sabin were assessed, a correlation between neurovirulence and the ability to replicate in primary human mononuclear blood cells was found. Surprisingly, infectious centers assays with primary human mononuclear blood cells and U937 cells indicated that despite the lower overall viral yield, more cells are initially infected with the attenuated viruses. These results indicate that there are virulence-specific differences in the ability of PV(1)Mahoney to replicate in monocytes and suggest that there may be factors in monocytes that virulent strains of PV require.
Assuntos
Leucócitos Mononucleares/virologia , Monócitos/virologia , Poliovirus/fisiologia , Poliovirus/patogenicidade , Replicação Viral , Linhagem Celular , Células HeLa , Humanos , Cinética , Especificidade da Espécie , VirulênciaRESUMO
Although the poliovirus receptor (PVR) has been cloned, lack of knowledge of its precise tissue distribution makes assessment of its role in mediating poliomyelitis difficult. Our recent work demonstrated that PVR is expressed on human monocytes and that primary human blood cells can support PV replication. In the current work, we demonstrate that CD14-positive cells (monocytes) support PV replication but that only a minority (< 10%) of the cells become infected. In other preliminary studies, immunocytochemical analyses of human brain tissue demonstrated the presence of PVR in the olfactory bulb, a tissue thought to not support PV replication. Thus, it appears that some apparently "ectopic" sites of PVR expression may in fact be sites for PV replication, whereas other sites may indeed be restricted. The ability of monocytes to replicate PV may pertain to some unexplained phenomena in PV pathogenesis, such as the specific cell type carrying out the initial round of replication in the gut, sites of extraneural replication and transport of the virus into the CNS. Preliminary studies with monocytes from post-polio syndrome patients showed no difference in the levels of PVR relative to control monocytes. In other preliminary work, PVR was shown to be phosphorylated and its expression on monocytes increased by treatment with gamma-interferon. The normal function of PVR is likely to be involved in monocyte function during immune activation.