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1.
Unfallchirurg ; 118(7): 643-6, 2015 Jul.
Artículo en Alemán | MEDLINE | ID: mdl-25312681

RESUMEN

The treatment of open fractures is a challenge for the attending surgeon. Depending on the severity, the risk of infection rises up to 50%. Local infection up to the point of sepsis can develop in spite of surgical and antimicrobial therapy. The present case demonstrates the case of an 18-year-old man who developed toxic shock syndrome (TSS) after an open ankle fracture. This potentially life-threating syndrome usually presents with the main symptoms of fever, hypotension and exanthema and is caused by toxins, such as toxic shock syndrome toxin 1 (TSST-1) and staphylococcal enterotoxins A-D. In some cases it is associated with cardiopulmonary decompensation and can rapidly progress to multiorgan failure.


Asunto(s)
Fracturas de Tobillo/diagnóstico , Fracturas de Tobillo/terapia , Fracturas Abiertas/diagnóstico , Fracturas Abiertas/terapia , Choque Séptico/diagnóstico , Choque Séptico/terapia , Adolescente , Terapia Combinada/métodos , Diagnóstico Diferencial , Humanos , Masculino , Resultado del Tratamiento
2.
Dtsch Med Wochenschr ; 139(25-26): 1377-82, 2014 Jun.
Artículo en Alemán | MEDLINE | ID: mdl-24914516

RESUMEN

Surveillance reports on infectious agents and their antibiotic resistance patterns as well as on the usage of antibiotics are now enforced by law for many medical institutions in Germany. However, specific practice-oriented recommendations concerning the appropriate extent and informative mode of presentation are lacking. This consensus statement resulted from the experience from five German university hospitals in handling data from infection epidemiology and in the various possibilities for the presentation of surveillance reports. The consensus statement provides recommendations for the preparation of the legally demanded surveillance reports, extending the existing regulations. The relevance of statements on frequency and quality of microbiological tests is included. Furthermore, modes for the standardization of the data analysis are suggested in order to achieve a regional and national comparability of the results on a high quality level, similarly to the established standardized surveillance of nosocomial infections. This consensus statement describes the form in which the legally enforced reports can be presented in an informative and standardized way in order to facilitate the deduction and realization of preventive measurements.


Asunto(s)
Infecciones Bacterianas/diagnóstico , Infecciones Bacterianas/prevención & control , Técnicas Bacteriológicas/normas , Notificación de Enfermedades/normas , Farmacorresistencia Bacteriana , Vigilancia de la Población/métodos , Guías de Práctica Clínica como Asunto , Infecciones Bacterianas/epidemiología , Alemania/epidemiología , Humanos
3.
Artículo en Alemán | MEDLINE | ID: mdl-21698542

RESUMEN

The program package "Integrated Bulletin for Infectious disease Surveillance for Schleswig-Holstein" (IBIS(SH)) was introduced in 2008 for the automated data analysis of notifiable infectious diseases in Schleswig-Holstein, Germany. The Java-based IBIS(SH) software supports access to the national SurvNet@RKI reporting data via Access and MS SQL. The aim of the IBIS(SH) system is early warning and interpretation of clusters and monitoring of trends. One module of the system permits the analysis of temporal aberration by comparison of data from previous years. The interpretation system is based on the weekly median and on percentile values from previous years. The extent of an aberration is assessed by a five-step score magnitude scale. Another module permits the detection of regional clusters by the weekly assessment of a population-based risk analysis. IBIS(SH) automatically generates tables and graphs for the weekly bulletin and their allocation in the Internet. Data for the most relevant pathogens in Schleswig-Holstein are presented for the year 2009. The performance of the automated temporal and the regional detection systems are compared to outbreak detection by local health authorities.


Asunto(s)
Control de Enfermedades Transmisibles/métodos , Enfermedades Transmisibles/epidemiología , Notificación de Enfermedades/métodos , Notificación de Enfermedades/estadística & datos numéricos , Cómputos Matemáticos , Vigilancia de la Población/métodos , Programas Informáticos , Análisis por Conglomerados , Gráficos por Computador , Alemania , Humanos
4.
Artículo en Alemán | MEDLINE | ID: mdl-20853089

RESUMEN

To obtain reliable, regionalized, and timely data for the spread of seasonal influenza in various age groups, which are preferentially affected by the influenza virus, a syndromic surveillance system for acute respiratory tract infections in Schleswig-Holstein (SHARE) was established in preschools and nurseries starting in 2006. The Schleswig-Flensburg district with 12 of 114 preschools and nurseries and 850 of 5,750 supervised children served as a pilot district. The weekly rates of sickness absenteeism correlated most strongly with the onset of seasonal influenza and with population density during the first half of the year. Mean annual sickness absenteeism levels of above 6% occurred more frequently above a population density of 200 inhabitants/km(2) than below this density (relative risk 2.50, 95% confidence interval 1.18-5.32). By analysis of the receiver-operating characteristic curve, the diagnostic performance of the SHARE system as a classifier for seasonal influenza was determined. The sensitivity was 83% and the specificity was 79% when sickness absence rates exceeded 5%. The performance of the SHARE system correlated with the size of the kindergarten. In 2008, 13 of 15 districts of Schleswig-Holstein participated with 157 of 1,684 kindergarten and 10,300 of 113,000 children. The evaluation for 2008 confirmed that the SHARE system is suitable for the surveillance of seasonal influenza at the district and state levels.


Asunto(s)
Guarderías Infantiles/estadística & datos numéricos , Gripe Humana/epidemiología , Vigilancia de la Población/métodos , Infecciones del Sistema Respiratorio/epidemiología , Escuelas de Párvulos/estadística & datos numéricos , Absentismo , Enfermedad Aguda , Preescolar , Recolección de Datos , Femenino , Alemania , Humanos , Gripe Humana/clasificación , Masculino , Proyectos Piloto , Densidad de Población , Curva ROC , Infecciones del Sistema Respiratorio/clasificación , Síndrome
5.
Clin Infect Dis ; 50(8): 1112-9, 2010 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-20205588

RESUMEN

BACKGROUND: This article describes multiple transmissions of rabies via transplanted solid organ from a single infected donor. The empirical Milwaukee treatment regimen was used in the recipients. METHODS: Symptomatic patients were treated by deep sedation (ketamine, midazolam, and phenobarbital), ribavirin, interferon, and active and passive vaccination. Viral loads and antibodies were continuously monitored. RESULTS: Recipients of both cornea and liver transplants developed no symptoms. The recipient of the liver transplant had been vaccinated approximately 20 years before transplantation. Two recipients of kidney and lung transplants developed rabies and died within days of symptomatic disease. Another kidney recipient was treated 7 weeks before he died. The cerebrospinal fluid viral load remained at constant low levels (<10,000 copies/mL) for approximately 5 weeks; it increased suddenly by almost 5 orders of magnitude thereafter. After death, no virus was found in peripheral compartments (nerve tissue, heart, liver, or the small intestine) in this patient, in contrast to in patients in the same cohort who died early. CONCLUSIONS: Our report includes, to our knowledge, the longest documented treatment course of symptomatic rabies and the first time that the virus concentration was measured over time and in different body compartments. The postmortem virus concentration in the periphery was low, but there was no evidence of a reduction of virus in the brain.


Asunto(s)
Anticuerpos Antivirales/administración & dosificación , Antivirales/uso terapéutico , Hipnóticos y Sedantes/uso terapéutico , Trasplante de Órganos/efectos adversos , Vacunas Antirrábicas/administración & dosificación , Virus de la Rabia/aislamiento & purificación , Rabia/tratamiento farmacológico , Adulto , Anciano , Anticuerpos Antivirales/sangre , Femenino , Humanos , Masculino , Persona de Mediana Edad , Vacunas Antirrábicas/inmunología , Resultado del Tratamiento , Carga Viral
6.
Gene Ther ; 17(5): 653-61, 2010 May.
Artículo en Inglés | MEDLINE | ID: mdl-20164858

RESUMEN

The rhadinovirus herpesvirus saimiri (HVS) as a gene delivery vector allows large DNA insertions and long-termed gene expression. In the case of T-cell transduction, such vectors use the viral transformation-associated genes of HVS C488 for T-cell amplification. In this report, we investigated whether the gene for the catalytic telomerase subunit human telomerase reverse transcriptase (hTERT) can substitute for the transformation-associated genes in rhadinoviral T-cell transduction and amplification. By using virus mutants generated by en passant mutagenesis from bacterial artificial chromosomes, we observed a very early and functional transgene expression even by virus mutants without transformation-associated genes. The markers of T-cell transformation by HVS, namely CD2 hyperreactivity, overexpression of interleukin-26, and of the tyrosine kinase Lyn could neither be induced nor enhanced by ectopic hTERT expression. When the viral transformation-associated genes were replaced by the hTERT gene, it was not sufficient for growth transformation, although hTERT was efficiently transduced and functionally expressed by the rhadinovirus vector. Thus, the transformation-associated proteins StpC and Tip are responsible for the T-cell phenotype after transduction by HVS and, additionally, modulate telomerase activity independently of hTERT expression.


Asunto(s)
Transformación Celular Viral/genética , Vectores Genéticos , Herpesvirus Saimiriino 2/genética , Linfocitos T/enzimología , Telomerasa/genética , Transducción Genética/métodos , Antígenos CD2/inmunología , Herpesvirus Saimiriino 2/inmunología , Humanos , Interleucinas/inmunología , Fosfoproteínas/genética , Proteínas Virales/genética , Familia-src Quinasas/análisis , Familia-src Quinasas/inmunología
7.
Ophthalmologe ; 106(12): 1058-64, 2009 Dec.
Artículo en Alemán | MEDLINE | ID: mdl-19820950

RESUMEN

Varicella zoster virus is the most frequent cause of acute retinal necrosis (ARN) followed by herpes simplex virus. Retinal ischemia and optic nerve atrophy are the main causes of the frequently poor final visual outcome in severe cases of ARN. The clinical diagnosis of ARN should be made as early as possible. Acyclovir should be administered intravenously due to its unreliable oral bioavailability. Systemic corticosteroids should be applied to suppress tissue damage caused by the host's inflammatory response. Severe cases of ARN should be treated by early vitrectomy with diagnostic vitreous biopsy, intravitreal aciclovir lavage, intraoperative laser retinopexy and silicone oil tamponade. The role of prophylactic laser retinopexy for prevention of secondary retinal detachment remains to be determined. The cause of different degrees of severity of ARN is unknown. The degree of severity of ARN is probably an independent predictor of the functional outcome.


Asunto(s)
Infecciones Virales del Ojo/diagnóstico , Infecciones Virales del Ojo/terapia , Síndrome de Necrosis Retiniana Aguda/diagnóstico , Síndrome de Necrosis Retiniana Aguda/terapia , Infecciones Virales del Ojo/complicaciones , Humanos , Síndrome de Necrosis Retiniana Aguda/etiología
8.
Ophthalmologe ; 106(12): 1065-73, 2009 Dec.
Artículo en Alemán | MEDLINE | ID: mdl-19838711

RESUMEN

Acute retinal necrosis occurs in approximately one per million persons per year and is caused in approximately 70% of the cases by the varicella zoster virus or in about 30% of the cases by herpes simplex virus. The early diagnosis is primarily based on virus-specific polymerase chain reaction in fluid from the anterior chamber or vitreous humor and can be supported by the determination of specific antibody titers from fluid and serum. Virus detection provides the basis for early causative therapy which limits disease progression and risk of complications. Retinal infections by varicella zoster virus or herpes simplex virus are treated with aciclovir, ganciclovir, or famciclovir. Ganciclovir and valganciclovir are used for the therapy of retinal cytomegalovirus infections. In the case of resistance development, foscarnet or cidofovir are available as second line antiviral drugs. The early use of specific antiviral agents is a crucial prerequisite for optimized therapy of acute retinal necrosis.


Asunto(s)
Infecciones Virales del Ojo/diagnóstico , Infecciones Virales del Ojo/terapia , Síndrome de Necrosis Retiniana Aguda/diagnóstico , Síndrome de Necrosis Retiniana Aguda/terapia , Infecciones Virales del Ojo/virología , Humanos , Síndrome de Necrosis Retiniana Aguda/virología
9.
Klin Monbl Augenheilkd ; 225(3): 236-9, 2008 Mar.
Artículo en Alemán | MEDLINE | ID: mdl-18351539

RESUMEN

BACKGROUND: Necrotising retinopathy in immunocompromised hosts is characterised by an unfavourable course often with unspecific clinical features. Therefore, differential diagnosis can be critical. HISTORY AND SIGNS: A case of an initially therapy-resistant, necrotizing retinopathy is presented in a 65-year-old immunocompromised male patient suffering from chronic B-cell leukemia. THERAPY AND OUTCOME: Despite demonstration of cytomegalovirus and Varicella-Zoster-Virus DNA by polymerase chain reaction in vitreous, aqueous humour samples and from retinal biopsy with specific antiviral therapy, a progression of retinal necrosis was noted. Finally Toxoplasma gondii DNA was detected and retinal necrosis resolved after specific treatment. However, visual acuity remains poor because of optic nerve atrophy. CONCLUSIONS: The polymerase chain reaction is an important diagnostic tool for differential diagnosis in immunocompromised patients suffering from necrotising retinopathy. If resistance to therapy is noted atypical ocular toxoplasmosis should be considered. The presented case report shows that even multiple infections are possible in the same host.


Asunto(s)
Coriorretinitis/diagnóstico , Infecciones por Citomegalovirus/diagnóstico , Citomegalovirus/fisiología , Herpes Zóster Oftálmico/diagnóstico , Herpesvirus Humano 3 , Leucemia Linfocítica Crónica de Células B/inmunología , Infecciones Oportunistas/diagnóstico , Toxoplasmosis Ocular/diagnóstico , Activación Viral , Anciano , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Ceguera/diagnóstico , Ceguera/inmunología , Clorambucilo/administración & dosificación , Clorambucilo/efectos adversos , Coriorretinitis/inmunología , Comorbilidad , Infecciones por Citomegalovirus/inmunología , Estudios de Seguimiento , Herpes Zóster Oftálmico/inmunología , Herpesvirus Humano 3/fisiología , Humanos , Tolerancia Inmunológica/inmunología , Leucemia Linfocítica Crónica de Células B/tratamiento farmacológico , Masculino , Infecciones Oportunistas/inmunología , Atrofia Óptica/diagnóstico , Atrofia Óptica/inmunología , Prednisolona/administración & dosificación , Prednisolona/efectos adversos , Síndrome de Necrosis Retiniana Aguda/diagnóstico , Síndrome de Necrosis Retiniana Aguda/inmunología , Toxoplasmosis Ocular/inmunología , Activación Viral/inmunología
10.
J Virol ; 75(19): 9252-61, 2001 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11533187

RESUMEN

Herpesvirus saimiri is capable of transforming T lymphocytes of various primate species to stable growth in culture. The interaction of the T-cellular tyrosine kinase p56(lck) with the transformation-associated viral protein Tip has been shown before to activate the kinase and provides one model for the T-cell-specific transformation by herpesvirus saimiri subgroup C strains. In contrast to other primate species, squirrel monkeys (Saimiri sciureus) are naturally infected with the virus without signs of lymphoma or other disease. Although the endogenous virus was regularly recovered from peripheral blood cells from squirrel monkeys, we observed that the T cells lost the virus genomes in culture. Superinfection with virus strain C488 did not induce growth transformation, in contrast to parallel experiments with T cells of other primate species. Surprisingly, p56(lck) was enzymatically inactive in primary T-cell lines derived from different squirrel monkeys, although the T cells reacted appropriately to stimulatory signals. The cDNA sequence revealed minor point mutations only, and transfections in COS-7 cells demonstrated that the S. sciureus lck gene codes for a functional enzyme. In S. sciureus, the tyrosine kinase p56(lck) was not activated after T-cell stimulation and enzymatic activity could not be induced by Tip of herpesvirus saimiri C488. However, the suppression of p56(lck) was partially released after administration of the phosphatase inhibitor pervanadate. This argues for unique species-specific conditions in T cells of S. sciureus which may interfere with the transforming activity and pathogenicity of herpesvirus saimiri subgroup C strains in their natural host.


Asunto(s)
Infecciones por Herpesviridae/inmunología , Herpesvirus Saimiriino 2/fisiología , Proteína Tirosina Quinasa p56(lck) Específica de Linfocito/inmunología , Linfocitos T/inmunología , Linfocitos T/virología , Infecciones Tumorales por Virus/inmunología , Secuencia de Aminoácidos , Animales , Transformación Celular Viral , Regulación hacia Abajo , Infecciones por Herpesviridae/enzimología , Humanos , Proteína Tirosina Quinasa p56(lck) Específica de Linfocito/metabolismo , Datos de Secuencia Molecular , Saimiri , Alineación de Secuencia , Linfocitos T/enzimología , Replicación Viral
11.
Philos Trans R Soc Lond B Biol Sci ; 356(1408): 545-67, 2001 Apr 29.
Artículo en Inglés | MEDLINE | ID: mdl-11313011

RESUMEN

Herpesvirus saimiri (saimiriine herpesvirus 2) is the classical prototype of the gamma(2)-herpesviruses or rhadinoviruses, which also contains a human member, the Kaposi's sarcoma-associated herpesvirus. The T-lymphotropic Herpesvirus saimiri establishes specific replicative and persistent conditions in different primate host species. Virtually all squirrel monkeys (Saimiri sciureus) are persistently infected with this virus. In its natural host, the virus does not cause disease, whereas it induces fatal acute T-cell lymphoma in other monkey species after experimental infection. The virus can be isolated by cocultivation of permissive epithelial cells with peripheral blood cells from naturally infected squirrel monkeys and from susceptible New World monkeys during the virus-induced disease. Tumour-derived and in vitro-transformed T-cell lines from New World monkeys release virus particles. Herpesvirus ateles is a closely related virus of spider monkeys (Ateles spp.) and has similar pathogenic properties to Herpesvirus saimiri in other New World primate species. Similar to other rhadinoviruses, the genome of Herpesvirus saimiri harbours a series of virus genes with pronounced homology to cellular counterparts including a D-type cyclin, a G-protein-coupled receptor, an interleukin-17, a superantigen homologue, and several inhibitors of the complement cascade and of different apoptosis pathways. Preserved function has been demonstrated for most of the homologues of cellular proteins. These viral functions are mostly dispensable for the transforming and pathogenic capability of the virus. However, they are considered relevant for the apathogenic persistence of Herpesvirus saimiri in its natural host. A terminal region of the non-repetitive coding part of the virus genome is essential for pathogenicity and T-cell transformation. Based on the pathogenic phenotypes and the different alleles of this variable region, the virus strains have been assigned to three subgroups, termed A, B and C. In the highly oncogenic subgroup C strains, the two virus genes stpC and tip are transcribed from one bicistronic mRNA and are essential for transformation and leukaemia induction. stpC fulfils the typical criteria of an oncogene; its product interacts with Ras and tumour necrosis factor-associated factors and induces mitogen-activated protein kinase and nuclear factor kappa B activation. Tip interacts with the RNA transport factor Tap, with signal transduction and activation of transcription factors, and with the T-cellular tyrosine kinase Lck, which is activated by this interaction and phosphorylates Tip as a substrate. It is of particular interest that certain subgroup C virus strains such as C488 are capable of transforming human T lymphocytes to stable growth in culture. The transformed human T cells harbour multiple copies of the viral genome in the form of stable, non-integrated episomes. The cells express only a few virus genes and do not produce virus particles. The transformed cells maintain the antigen specificity and many other essential functions of their parental T-cell clones. Based on the preserved functional phenotype of the transformed T cells, Herpesvirus saimiri provides useful tools for T-cell immunology, for gene transfer and possibly also for experimental adoptive immunotherapy.


Asunto(s)
Infecciones por Herpesviridae/virología , Herpesvirus Saimiriino 2/genética , Infecciones Tumorales por Virus/virología , Animales , Transformación Celular Viral , Técnicas de Transferencia de Gen , Genes Virales , Vectores Genéticos , Genoma Viral , Infecciones por Herpesviridae/patología , Herpesvirus Saimiriino 2/fisiología , Humanos , Linfocitos T/virología , Infecciones Tumorales por Virus/patología , Replicación Viral
12.
FASEB J ; 15(6): 1037-43, 2001 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-11292665

RESUMEN

Varicella-zoster virus (VZV) is a widespread human herpes virus causing chicken pox on primary infection and persisting in sensory neurons. Reactivation causes shingles, which are characterized by severe pain and often lead to postherpetic neuralgia. To elucidate the mechanisms of VZV-associated hyperalgesia, we elaborated an in vitro model for the VZV infection of sensory neurons from rat dorsal root ganglia. Between 35 and 50% of the neurons showed strong expression of the immediate-early virus antigens IE62 and IE63 and the late glycoprotein gE. When the intracellular calcium concentration was monitored microfluorometrically for individual cells after infection, the sensitivity to GABA or capsaicin was similar in controls and in VZV-infected neurons. However, the baseline calcium concentration was increased. Neurons became de novo sensitive to adrenergic stimulation after VZV infection. Norepinephrine-responsive neurons were more frequent and calcium responses to norepinephrine were significantly higher after infection with wild-type isolates than with the attenuated vaccine strain OKA. The adrenergic agonists phenylephrine and isoproterenol had similar efficacy. We suggest that the infection with wild-type VZV isolates confers norepinephrine sensitivity to sensory neurons by using alpha(1)- and/or beta(1)-adrenergic receptors providing a model for the pathophysiology of the severe pain associated with the acute reactivation of VZV.


Asunto(s)
Ganglios Espinales/efectos de los fármacos , Herpes Zóster/patología , Herpesvirus Humano 3 , Neuronas Aferentes/efectos de los fármacos , Norepinefrina/farmacología , Animales , Células Cultivadas , Técnicas de Cocultivo , Femenino , Ganglios Espinales/patología , Ganglios Espinales/virología , Humanos , Neuronas Aferentes/metabolismo , Neuronas Aferentes/virología , Ratas , Ratas Wistar , Receptores Adrenérgicos/metabolismo
13.
J Virol ; 75(8): 4008-13, 2001 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-11264393

RESUMEN

Herpesviruses occur in two distinct forms of infection, lytic replication and latent persistence. In this study, we investigated the molecular mechanisms that govern the latent-lytic switch in the prototype gamma-2 herpesvirus, herpesvirus saimiri (HVS). We utilized a persistently HVS-infected A549 cell line, in which HVS DNA is stably maintained as nonintegrated circular episomes, to assess the role of the open reading frame 50 (ORF 50) (Rta) proteins in the latent-lytic switch. Northern blot analysis and virus recovery assays determined that the ORF 50a gene product, when expressed under the control of a constitutively active promoter, was sufficient to reactivate the entire lytic replication cycle, producing infectious virus particles. Furthermore, although the ORF 50 proteins of HVS strains A11 and C488 are structurally divergent, they were both capable of inducing the lytic replication cycle in this model of HVS latency.


Asunto(s)
Herpesvirus Saimiriino 2/fisiología , Sistemas de Lectura Abierta/genética , Transactivadores/metabolismo , Proteínas Virales/metabolismo , Activación Viral , Replicación Viral , ADN Viral/biosíntesis , ADN Viral/genética , Regulación Viral de la Expresión Génica , Herpesvirus Saimiriino 2/genética , Humanos , Transactivadores/genética , Células Tumorales Cultivadas , Proteínas Virales/genética , Latencia del Virus
14.
Virology ; 278(2): 445-55, 2000 Dec 20.
Artículo en Inglés | MEDLINE | ID: mdl-11118367

RESUMEN

Herpesvirus saimiri can be used as an efficient gene expression vector for human T lymphocytes and thus may allow applications in experimental leukemia therapy. We constructed recombinant viruses for the functional expression of the thymidine kinase (TK) of herpes simplex virus type 1 (HSV) as a suicide gene. These viruses reliably allowed the targeted elimination of transduced nonpermissive human T cells in vitro after the administration of ganciclovir. To test the reliability of this function under the most stringent permissive conditions, in this study we analyzed the influence of the prodrugs ganciclovir and acyclovir in common marmosets on the acute leukemogenesis induced by either wild-type herpesvirus saimiri C488 or by a recombinant derivative expressing TK of HSV. Antiviral drug treatment did not influence the rapid development of acute disease. In contrast, the presence of the HSV tk gene resulted in a faster disease progression. In addition, HSV TK-expressing viruses showed faster replication than wild-type virus in culture at low serum concentrations. Thus, HSV TK accelerates the replication of herpesvirus saimiri and enhances its pathogenicity. This should be generally considered when HSV TK is applied as a transgene in replication-competent DNA virus vectors for gene therapy.


Asunto(s)
Herpes Simple/patología , Leucemia de Células T/fisiopatología , Simplexvirus/genética , Simplexvirus/patogenicidad , Linfocitos T/virología , Timidina Quinasa/metabolismo , Aciclovir/farmacología , Animales , Callithrix , Línea Celular , Células Cultivadas , Ganciclovir/farmacología , Vectores Genéticos , Humanos , Leucemia de Células T/patología , Simplexvirus/enzimología , Linfocitos T/efectos de los fármacos , Timidina Quinasa/genética , Virulencia
15.
Blood ; 95(10): 3256-61, 2000 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-10807797

RESUMEN

Human T cells are transformed in vitro to stable growth after infection with herpesvirus saimiri subgroup C strain C488, and they retain their antigen-specific reactivity and other important functional features of mature activated T lymphocytes. The virus persists as nonintegrating episomes in human T cells under restricted viral gene expression and without production of virus particles. This study analyzes the behavior of herpesvirus-transformed autologous T cells after reinfusion into the donor under close-to-human experimental conditions. T cells of 5 macaque monkeys were transformed to stable interleukin-2 dependent growth and were intravenously infused into the respective donor. The animals remained healthy, without occurrence of lymphoma or leukemia for an observation period of more than 1 year. Over several months virus genomes were detectable in peripheral blood cells and in cultured T cells by polymerase chain reaction. In naive control animals, a high-dose intravenous infection rapidly induced pleomorphic peripheral T-cell lymphoma. In contrast, monkeys were protected from lymphoma after challenge infection if they had previously received autologous T-cell transfusions. High levels of antibodies against virus antigens were detectable after challenge infection only. Taken together, herpesvirus-transformed T cells are well tolerated after autologous reinfusion. This may allow us to develop a novel concept for adoptive T-cell mediated immunotherapy.


Asunto(s)
Transformación Celular Viral , Herpesvirus Saimiriino 2 , Tolerancia Inmunológica , Linfoma/etiología , Linfoma/patología , Linfocitos T/patología , Traslado Adoptivo , Animales , Transfusión de Sangre Autóloga , Humanos , Inmunoterapia Adoptiva , Transfusión de Linfocitos , Macaca mulatta , Linfocitos T/inmunología , Linfocitos T/virología
16.
Gene Ther ; 7(8): 664-74, 2000 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-10800089

RESUMEN

Herpesvirus saimiri transforms human T lymphocytes to stable growth and persists episomally without genomic integration and without virus production. The transformed T cells retain essential features of their parental cells including the MHC-restricted antigen specificity which may be useful for applications in adoptive immunotherapy. In order to improve the biological safety of such vectors, the prodrug activating gene thymidine kinase of herpes simplex virus was inserted into the genome of herpesvirus saimiri by homologous recombination. After infection with wild-type or cloned recombinant viruses, T cells from tamarin monkeys and from humans were transformed to stable growth. Thymidine kinase-expressing transformed T cells were efficiently eliminated in the presence of low concentrations of ganciclovir. This elimination mechanism remained fully functional over an observation period of 12 months. The potentially immunogenic neomycin resistance gene expression cassette was deleted from the genome of established mutant viruses by using the prokaryotic Cre/LoxP recombination system. At any time during the course of a therapeutic application, thymidine kinase-expressing transformed human T cells might be eliminated after administration of ganciclovir. In principle, this function could be useful for the T cell-dependent immunotherapy of resistant blood cancer while avoiding the risk of uncontrolled graft-versus-host disease.


Asunto(s)
Terapia Genética/métodos , Vectores Genéticos/administración & dosificación , Herpesvirus Saimiriino 2/genética , Linfocitos T/enzimología , Timidina Quinasa/genética , Aciclovir/uso terapéutico , Animales , Antimetabolitos Antineoplásicos/uso terapéutico , Antivirales/uso terapéutico , Células Cultivadas , Fluorouracilo/uso terapéutico , Ganciclovir/uso terapéutico , Expresión Génica , Vectores Genéticos/genética , Humanos , Recombinación Genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Saguinus , Transgenes
17.
J Virol ; 74(8): 3881-7, 2000 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-10729163

RESUMEN

Although herpesvirus saimiri-transformed T lymphocytes retain multiple normal T-cell functions, only a few changes have been described. By subtractive hybridization, we have isolated a novel cellular gene, ak155, a sequence homolog of the interleukin-10 gene. Specifically herpesvirus saimiri-transformed T cells overexpress ak155 and secrete the protein into the supernatant. In other T-cell lines and in native peripheral blood cells, but not in B cells, ak155 is transcribed at low levels. AK155 forms homodimers similarly to interleukin-10. As a lymphokine, AK155 may contribute to the transformed phenotype of human T cells after infection by herpesvirus saimiri.


Asunto(s)
Transformación Celular Viral , Herpesvirus Saimiriino 2/fisiología , Interleucina-10/genética , Interleucina-10/metabolismo , Interleucinas , Linfocitos T/virología , Secuencia de Aminoácidos , Línea Celular Transformada , Clonación Molecular , Humanos , Interleucina-10/química , Activación de Linfocitos , Datos de Secuencia Molecular , Hibridación de Ácido Nucleico , Alineación de Secuencia , Homología de Secuencia de Aminoácido , Linfocitos T/inmunología , Transcripción Genética
18.
Virology ; 268(1): 167-77, 2000 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-10683339

RESUMEN

The transformation-associated region of herpesvirus saimiri strains is variable, whereas other parts of the virus genome are highly conserved. However, we observed considerable interstrain sequence divergence of the early viral regulatory orf50 gene, which encodes the R transactivator, a homolog of Epstein-Barr virus BRLF1. The orf50 gene of strain C488 was transcribed at low abundance during lytic infection, whereas antisense transcripts were simultaneously expressed at high levels. A spliced variant, orf50a, was detectable by RT-PCR and RNase protection assays in stimulated C488-transformed, nonpermissive human T cells. In contrast to strain A11, the short, unspliced orf50b form of C488 displayed complete transactivation capability on the orf6 and orf57 promoters. In summary, there are unexpected structural and functional differences between the orf50 genes of herpesvirus saimiri strains, which differ in their capability to transform human T lymphocytes.


Asunto(s)
Transformación Celular Viral , Herpesvirus Saimiriino 2/genética , Herpesvirus Saimiriino 2/fisiología , Linfocitos T/virología , Transactivadores/genética , Activación Transcripcional , Secuencia de Aminoácidos , Animales , Línea Celular Transformada , Regulación Viral de la Expresión Génica , Genes Virales , Humanos , Datos de Secuencia Molecular , Sistemas de Lectura Abierta/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Transactivadores/química , Replicación Viral
20.
J Virol Methods ; 79(1): 51-63, 1999 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-10328535

RESUMEN

A better characterisation of mononuclear cell-tropic (M-tropic) HIV-1 is central to disease control as these viruses predominate in disease transmission. M-tropic viruses do not replicate in conventional T-cell lines, and virus titres obtained in peripheral blood mononuclear cells (PBMC) are low. Human T-lymphocytes which have been immortalised by Herpesvirus saimiri strain C488 (HVS T-cells) are highly permissive to the replication of T-cell tropic strains of HIV. This study aimed to determine if HVS T-cells support replication of M-tropic HIV isolates that have not been adapted to conventional T-cell lines. A panel of PBMC low passage/primary field isolates and their molecular clones was used. Results show that infection in HVS T-cells was longer lived than in PBMC. In terms of peak virus titre and duration of productive infection, the two HVS T-cell lines studied were superior to PBMC, and one supported enhanced replication of all M-tropic isolates. This is important for generating M-tropic virus pools of sufficient titre for further biological studies such as virus neutralisation, co receptor usage and testing of antivirals. Phenotypic analysis showed that HVS T-cells are CD4+-activated memory cells expressing both CXCR-4 and CCR5 co receptors. Thus, HVS immortalisation appears to select for the T-cell subset targeted by HIV-1 in vivo.


Asunto(s)
Linfocitos T CD4-Positivos/virología , VIH-1/fisiología , Herpesvirus Saimiriino 2/fisiología , Receptores CCR5/metabolismo , Replicación Viral , Linfocitos T CD4-Positivos/metabolismo , Transformación Celular Viral , Quimiocina CCL5/metabolismo , Ensayo de Inmunoadsorción Enzimática , Citometría de Flujo , Humanos , Leucocitos Mononucleares/metabolismo , Leucocitos Mononucleares/virología , Macrófagos/virología , Subgrupos de Linfocitos T/metabolismo , Subgrupos de Linfocitos T/virología , Tropismo/fisiología
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