RESUMEN
Most human immunodeficiency virus (HIV) transmissions in women occur through the cervicovaginal mucosa, which is coated by a bacterial biofilm including Lactobacillus. This commensal bacterium has a role in maintaining a healthy mucosa and can be genetically engineered to produce antiviral peptides. Here, we report a 63% reduction in transmission of a chimeric simian/HIV (SHIV(SF162P3)) after repeated vaginal challenges of macaques treated with Lactobacillus jensenii expressing the HIV-1 entry inhibitor cyanovirin-N. Furthermore, peak viral loads in colonized macaques with breakthrough infection were reduced sixfold. Colonization and prolonged antiviral protein secretion by the genetically engineered lactobacilli did not cause any increase in proinflammatory markers. These findings lay the foundation for an accessible and durable approach to reduce heterosexual transmission of HIV in women, which is coitally independent, inexpensive, and enhances the natural protective effects of the vaginal microflora.
Asunto(s)
Proteínas Bacterianas/metabolismo , Proteínas Portadoras/metabolismo , Infecciones por VIH/microbiología , VIH/inmunología , Lactobacillus/inmunología , Vagina/metabolismo , Administración Intravaginal , Animales , Proteínas Bacterianas/genética , Proteínas Bacterianas/inmunología , Proteínas Portadoras/genética , Proteínas Portadoras/inmunología , Citocinas/sangre , Modelos Animales de Enfermedad , Femenino , Ingeniería Genética , VIH/genética , VIH/patogenicidad , Infecciones por VIH/inmunología , Infecciones por VIH/transmisión , Humanos , Inmunidad Mucosa/genética , Lactobacillus/genética , Lactobacillus/crecimiento & desarrollo , Lactobacillus/metabolismo , Macaca mulatta , Proteínas Recombinantes de Fusión/genética , Virus de la Inmunodeficiencia de los Simios/genética , Vagina/inmunología , Vagina/microbiología , Carga Viral , Internalización del VirusRESUMEN
Infection and dissemination of human immunodeficiency virus (HIV)-1 through the female body after vaginal intercourse depends on the activation/differentiation status of mucosal CD4 T cells. In this study, we investigated this status and the susceptibility to HIV-1 infection of human cervico-vaginal tissue ex vivo. We found that virtually all T cells are of the effector memory phenotype with broad CC chemokine receptor 5 (CCR5) expression. As it does in vivo, human cervico-vaginal tissue ex vivo preferentially supports the productive infection of R5 HIV-1 rather than that of X4 HIV-1 in spite of the broad expression of CXC chemokine receptor 4 (CXCR4). X4 HIV-1 replicated only in the few tissues that were enriched in CD27(+)CD28(+) effector memory CD4 T cells. Productive infection of R5 HIV-1 occurred preferentially in activated CD38(+)CD4 T cells and was followed by a similar activation of HIV-1-uninfected (bystander) CD4 T cells that may amplify viral infection. These results provide new insights into the dependence of HIV-1 infection and dissemination on the activation/differentiation of cervico-vaginal lymphocytes.
Asunto(s)
Linfocitos T CD4-Positivos/inmunología , Infecciones por VIH/inmunología , Infecciones por VIH/transmisión , VIH-1/inmunología , Replicación Viral/inmunología , ADP-Ribosil Ciclasa 1/inmunología , ADP-Ribosil Ciclasa 1/metabolismo , Efecto Espectador/inmunología , Linfocitos T CD4-Positivos/metabolismo , Linfocitos T CD4-Positivos/virología , Cuello del Útero , Femenino , Infecciones por VIH/metabolismo , VIH-1/metabolismo , Humanos , Masculino , Glicoproteínas de Membrana/inmunología , Glicoproteínas de Membrana/metabolismo , Receptores CCR5/inmunología , Receptores CCR5/metabolismo , Receptores CXCR4/inmunología , Receptores CXCR4/metabolismo , Técnicas de Cultivo de Tejidos , VaginaAsunto(s)
Fármacos Anti-VIH/uso terapéutico , Terapia Antirretroviral Altamente Activa , Quimiocinas CC/uso terapéutico , Infecciones por VIH/tratamiento farmacológico , VIH-1 , Fármacos Anti-VIH/efectos adversos , Quimiocinas CC/efectos adversos , Quimiocinas CC/sangre , Infecciones por VIH/inmunología , HumanosRESUMEN
Infection of macrophage lineage cells is a feature of primate lentivirus replication, and several properties of primate lentiviruses seem to have evolved to promote the infection of macrophages. Here we demonstrate that the accessory gene product Nef induces the production of two CC-chemokines, macrophage inflammatory proteins 1alpha and 1beta, by HIV-1-infected macrophages. Adenovirus-mediated expression of Nef in primary macrophages was sufficient for chemokine induction. Supernatants from Nef-expressing macrophages induced both the chemotaxis and activation of resting T lymphocytes, permitting productive HIV-1 infection. These results indicate a role for Nef in lymphocyte recruitment and activation at sites of virus replication.
Asunto(s)
Quimiotaxis , Productos del Gen nef/fisiología , VIH-1/fisiología , Activación de Linfocitos , Macrófagos/virología , Linfocitos T/inmunología , Adenoviridae/genética , Animales , Línea Celular , Células Cultivadas , Quimiocina CCL4 , Quimiocinas/biosíntesis , Quimiocinas/genética , Quimiotaxis/efectos de los fármacos , Medios de Cultivo Condicionados , Citocinas/biosíntesis , Encefalitis Viral/inmunología , Encefalitis Viral/virología , Productos del Gen nef/genética , VIH-1/efectos de los fármacos , VIH-1/genética , VIH-1/crecimiento & desarrollo , Humanos , Activación de Linfocitos/efectos de los fármacos , Macaca , Proteínas Inflamatorias de Macrófagos/biosíntesis , Proteínas Inflamatorias de Macrófagos/genética , Macrófagos/inmunología , Macrófagos/metabolismo , Mutación , Virus de la Inmunodeficiencia de los Simios/efectos de los fármacos , Virus de la Inmunodeficiencia de los Simios/crecimiento & desarrollo , Virus de la Inmunodeficiencia de los Simios/fisiología , Linfocitos T/efectos de los fármacos , Linfocitos T/virología , Replicación Viral/efectos de los fármacos , Productos del Gen nef del Virus de la Inmunodeficiencia HumanaRESUMEN
After interaction of human immunodeficiency virus type 1 (HIV-1) virions with cell surface receptors, a series of poorly characterized events results in establishment of a viral reverse transcription complex in the host cell cytoplasm. This process is coordinated in such a way that reverse transcription is initiated shortly after formation of the viral reverse transcription complex. However, the mechanism through which virus entry and initiation of reverse transcription are coordinated and how these events are compartmentalized in the infected cell are not known. In this study, we demonstrate that viral reverse transcription complexes associate rapidly with the host cell cytoskeleton during HIV-1 infection and that reverse transcription occurs almost entirely in the cytoskeletal compartment. Interruption of actin polymerization before virus infection reduced association of viral reverse transcription complexes with the cytoskeleton. In addition, efficient reverse transcription was dependent on intact actin microfilaments. The localization of reverse transcription to actin microfilaments was mediated by the interaction of a reverse transcription complex component (gag MA) with actin but not vimentin (intermediate filaments) or tubulin (microtubules). In addition, fusion, but not endocytosis-mediated HIV-1 infectivity, was impaired when actin depolymerizing agents were added to target cells before infection but not when added after infection. These results point to a previously unsuspected role for the host cell cytoskeleton in HIV-1 entry and suggest that components of the cytoskeleton promote establishment of the reverse transcription complex in the host cell and also the process of reverse transcription within this complex.
Asunto(s)
Citoesqueleto/virología , Infecciones por VIH/virología , VIH-1/fisiología , Replicación Viral , Línea Celular , Infecciones por VIH/patología , Transcriptasa Inversa del VIH , HumanosRESUMEN
The viral accessory protein Vpx is required for productive in vitro infection of macrophages by simian immunodeficiency virus from sooty mangabey monkeys (SIV(SM)). To evaluate the roles of Vpx and macrophage infection in vivo, we inoculated pigtailed macaques intravenously or intrarectally with the molecularly cloned, macrophage tropic, acutely pathogenic virus SIV(SM) PBj 6.6, or accessory gene deletion mutants (deltaVpr or deltaVpx) of this virus. Both wild-type and SIV(SM) PBj deltaVpx viruses were readily transmitted across the rectal mucosa. A subsequent 'stepwise' process of local amplification of infection and dissemination was observed for wild-type virus, but not for SIV(SM) PBj deltaVpx, which also showed considerable impairment of the overall kinetics and extent of its replication. In animals co-inoculated with equivalent amounts of wild-type and SIV(SM) Pbj deltaVpx intravenously or intrarectally, the deltaVpx mutant was at a strong competitive disadvantage. Vpx-dependent viral amplification at local sites of initial infection, perhaps through a macrophage-dependent mechanism, may be a prerequisite for efficient dissemination of infection and pathogenic consequences after exposure through either mucosal or intravenous routes.
Asunto(s)
Macrófagos/inmunología , Macrófagos/virología , Virus de la Inmunodeficiencia de los Simios/patogenicidad , Proteínas Reguladoras y Accesorias Virales/fisiología , Animales , Cercocebus atys , Genotipo , Inmunohistoquímica , Hibridación in Situ , Mucosa Intestinal/virología , Macaca nemestrina , Síndrome de Inmunodeficiencia Adquirida del Simio/inmunología , Síndrome de Inmunodeficiencia Adquirida del Simio/virología , Virus de la Inmunodeficiencia de los Simios/genética , Virus de la Inmunodeficiencia de los Simios/fisiología , Carga Viral , Replicación ViralRESUMEN
Infection of a cell by human immunodeficiency virus type 1 (HIV-1) results in the formation of a reverse transcription complex in which viral nucleic acids are synthesized. Efficient disengagement of the reverse transcription complex from the cell membrane and subsequent nuclear translocation require phosphorylation of reverse transcription complex components by a virion-associated kinase. In this study, we identify the virion-associated kinase as mitogen-activated protein kinase (ERK/MAPK). Upon density gradient fractionation, MAPK, but not its activating kinase MEK, co-sedimented with viral particles. Expression of a constitutively active, but not kinase-inactive, MEK1 in virus producer cells was able to activate virion-associated MAPK in trans. Stimulation of virion-associated MAPK activity in trans by the mitogen phorbol myristate acetate (PMA) increased viral infectivity. Conversely, suppression of virion-associated MAPK by specific inhibitors of the MAPK cascade markedly impaired viral infectivity. These studies demonstrate regulation of an early step in HIV-1 infection by the host cell MAPK signal transduction pathway.
Asunto(s)
Proteínas Quinasas Dependientes de Calcio-Calmodulina/metabolismo , VIH-1/fisiología , Quinasas de Proteína Quinasa Activadas por Mitógenos , Antígenos CD4/biosíntesis , Antígenos CD4/fisiología , Línea Celular , Membrana Celular/fisiología , Núcleo Celular/fisiología , Transcriptasa Inversa del VIH/metabolismo , VIH-1/patogenicidad , Células HeLa , Humanos , Riñón , Cinética , MAP Quinasa Quinasa 1 , Reacción en Cadena de la Polimerasa , Proteínas Serina-Treonina Quinasas/metabolismo , Proteínas Tirosina Quinasas/metabolismo , Proteínas Recombinantes de Fusión/biosíntesis , Acetato de Tetradecanoilforbol/farmacología , Transfección , Virión/patogenicidad , Virión/fisiología , Replicación Viral/efectos de los fármacos , Replicación Viral/fisiologíaRESUMEN
Quantitative competitive PCR is a highly sensitive technique that allows accurate quantitation of small amounts of RNA. We have modified the original method to include the use of an internal standard at all stages of sample analysis. In this way, the method can accommodate for variations in the recovery of viral particles and in the isolation of genomic RNA as well as provide a suitable competitive substrate during quantitative RNA PCR. We have used this method to characterize changes in virus load in plasma of HIV-1-seropositive individuals following their vaccination against opportunistic infections.
Asunto(s)
VIH-1/aislamiento & purificación , Reacción en Cadena de la Polimerasa/métodos , ARN Viral/sangre , Virión/genética , Southern Blotting , Electroforesis en Gel de Agar , VIH-1/genética , Humanos , Estándares de ReferenciaRESUMEN
X-linked lymphoproliferative disease (XLP) is characterized by a marked vulnerability to Epstein-Barr virus (EBV) infection. Infection of XLP patients with EBV invariably results in fatal mononucleosis, agammaglobulinemia, or malignant lymphoma. Initially the XLP gene was assigned to a 10-cM region in Xq25 between DXS42 and DXS37. Subsequently, an interstitial, cytogenetically visible deletion in Xq25 was identified in one XLP family, 43. In this study we estimated the deletion in XLP patient 43-004 by dual-laser flow karyotyping to involve 2% of the X chromosome, or approximately 3 Mb of DNA sequence. From a human chromosome Xq25-specific yeast artificial chromosome (YAC) sublibrary, five YACs containing DNA sequences deleted in patient 43-004 have been isolated. Sequence-tagged sites (STSs) from these YACs have been used to identify interstitial deletions in unrelated XLP patients. Three more families with interstitial deletions were found. Two of the patients (63-003 and 73-032) carried an interstitial deletion of 3.0 Mb overlapping the 43-004 deletion. In one XLP patient (30-011) who exhibited the characteristic postinfectious mononucleosis phenotype of XLP with hypogammaglobulinemia and malignant lymphoma, a deletion of approximately 250 kb was detected overlapping the deletion detected in patients 43-004, 63-003, and 73-032. A YAC contig of 2.2 Mb spanning the XLP critical region, whose orientation on chromosome X was determined by double-color fluorescence in situ hybridization and which consists of 15 overlapping YAC clones, has been constructed. A detailed restriction enzyme map of the region has been constructed. YAC insert sizes were determined by counter-clamped homogenous electric field gel electrophoresis. Chimerism of YACs was determined by FISH and restriction mapping. On the basis of lambda subclones, YAC end-derived plasmids, and STSs with an average spacing of 100 kb, a long-range physical map was constructed using 5 rare-cutter restriction enzymes. The STSs and lambda subclones were used in Southern hybridization and PCR analyses. The work presented here substantially refines the critical region for XLP. The YAC contig with the overlapping interstitial deletions constitutes the basis for the construction of a transcriptional map of the critical region and facilitates the identification of the XLP gene.
Asunto(s)
Cromosomas Artificiales de Levadura , Ligamiento Genético , Trastornos Linfoproliferativos/genética , Cromosoma X , Citometría de Flujo , Marcadores Genéticos , Humanos , Cariotipificación , Secuencias Repetitivas de Ácidos Nucleicos , Mapeo Restrictivo , Eliminación de Secuencia , Lugares Marcados de SecuenciaRESUMEN
Primary factors that influence virus burden during human immunodeficiency virus type 1 (HIV-1) disease progression remain a fundamental issue in pathogenesis. Because pneumococcal vaccine is routinely given to HIV-1-infected patients and replication of HIV-1 within CD4 T cells is dependent on the activation state of the cell, it was investigated whether the T cell activation that enhances the immune response to vaccines may also enhance HIV-1 replication. Vaccination of asymptomatic HIV-1-infected patients led to rapid and significant increases in virus burden in some patients. The magnitude of these increases correlated significantly with the extent of the antibody response to the vaccination. Thus, antigenic stimulation by vaccines designed to prevent secondary infections may promote HIV-1 replication in certain patients. These findings provide a window for examining HIV-1 pathogenesis and for determining the appropriate preventive measures against other diseases in HIV-1-infected persons.
Asunto(s)
Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD4-Positivos/virología , Infecciones por VIH/inmunología , Infecciones por VIH/virología , VIH-1/crecimiento & desarrollo , Infecciones Neumocócicas/inmunología , Infecciones Neumocócicas/prevención & control , Vacunas/efectos adversos , Vacunas/inmunología , Carga Viral , Adulto , Fármacos Anti-VIH/uso terapéutico , Anticuerpos Antibacterianos/análisis , Recuento de Linfocito CD4 , Linfocitos T CD8-positivos/inmunología , Linfocitos T CD8-positivos/virología , ADN Viral/análisis , Didanosina/uso terapéutico , Progresión de la Enfermedad , Infecciones por VIH/tratamiento farmacológico , VIH-1/patogenicidad , Humanos , Inmunoglobulina G/análisis , Vacunas contra la Influenza/inmunología , Activación de Linfocitos , Persona de Mediana Edad , Polisacáridos Bacterianos/inmunología , Provirus/genética , ARN Viral/análisis , Receptores de Interleucina-2/inmunología , Factores de Tiempo , Vacunación/efectos adversos , Zidovudina/uso terapéuticoRESUMEN
The vpr genes of human and simian immunodeficiency viruses (HIV/SIV) encode proteins which are packaged in the virus particle. HIV-1 Vpr has been shown to mediate the nuclear import of viral reverse transcription complexes in non-dividing target cells (e.g. terminally differentiated macrophages), and to alter the cell cycle and proliferation status of the infected host cell. Members of the HIV-2/SIV(SM) group encode, in addition to Vpr, a related protein called Vpx. Because these two proteins share considerable sequence similarity, it has been assumed that they also exhibit similar functions. Here, we report that the functions of Vpr and Vpx are distinct and non-redundant, although both proteins are components of the HIV-2/SIV(SM) virion and reverse transcription complex. Characterizing SIV(SM) proviruses defective in one or both genes, we found that Vpx is both necessary and sufficient for the nuclear import of the viral reverse transcription complex. In contrast, Vpr, but not Vpx, inhibited the progression of infected host cells from the G2 to the M phase of the cell cycle. Thus, two independent functions of the HIV-1 Vpr protein are encoded by separate genes in HIV-2/SIV(SM). This segregation is consistent with the conservation of these genes in HIV-2/SIV(SM) evolution, and underscores the importance of both nuclear transport and cell cycle arrest functions in primate lentivirus biology.
Asunto(s)
Productos del Gen vpr/metabolismo , Genes Virales/genética , VIH-2/metabolismo , Animales , Western Blotting , Ciclo Celular/genética , División Celular/efectos de los fármacos , Núcleo Celular/metabolismo , Células Cultivadas , ADN Viral/metabolismo , Productos del Gen gag/metabolismo , Productos del Gen vpr/farmacología , VIH-2/genética , Haplorrinos , Macrófagos/metabolismo , Macrófagos/virología , Mutagénesis Sitio-Dirigida/genética , ADN Polimerasa Dirigida por ARN/metabolismo , Proteínas Reguladoras y Accesorias Virales/metabolismo , Proteínas Reguladoras y Accesorias Virales/farmacología , Productos del Gen vpr del Virus de la Inmunodeficiencia HumanaRESUMEN
To examine a possible association between plasma viremia and interferon-alpha (IFN-alpha) in patients with the acquired immunodeficiency syndrome (AIDS), we performed IFN plasma immunoadsorption by apheresis (IFN-alpha apheresis) in four volunteers with AIDS who had sustained levels of endogenous plasma IFN-alpha. IFN-alpha apheresis with two plasma volume exchanges was performed daily for 5 days. Clinical signs and symptoms and hematologic, virologic, and immunologic parameters were monitored. Two subjects developed anemia from phlebotomy, and one had a catheter++-associated bacteremia. The IFN-alpha apheresis was effective only in transiently removing IFN-alpha: depletion of IFN-alpha led only to its rapid reconstitution. Cell-associated HIV-1 was unchanged, but three of four subjects had a modest decrease in culturable plasma virus burden following the procedures. The recovery of in vivo HIV-1-related IFN-alpha by apheresis allowed its biologic and biochemical characterization. The HIV-1 IFN-alpha showed characteristics on ELISA, western blot, and biologic assays similar to two subspecies of the natural protein. The natural, recombinant, and HIV-1-induced IFN-alpha s demonstrated nearly identical antiviral activities. The HIV-1 IFN-alpha eluted from the column was not acid labile. The inability of large amounts of plasma IFN-alpha found in some patients with AIDS to affect viral burden likely reflects properties of the virus or of host factors independent of IFN-alpha.
Asunto(s)
Síndrome de Inmunodeficiencia Adquirida/sangre , VIH-1 , Interferón-alfa/sangre , Síndrome de Inmunodeficiencia Adquirida/inmunología , Síndrome de Inmunodeficiencia Adquirida/virología , Adulto , Secuencia de Bases , Eliminación de Componentes Sanguíneos/efectos adversos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Datos de Secuencia Molecular , Replicación ViralRESUMEN
Research is beginning to yield insight into determinants which govern cell cycle dependence of provirus establishment by the onco-retroviruses. In the case of HIV-1, nucleophilic components associated with the viral preintegration complex facilitate mitosis independent nuclear localization of viral DNA and provirus establishment. Differences in the metabolic activity between G0 T cells and macrophages, the two primary targets for HIV-1 infection, lead to significantly different outcomes with regards to provirus establishment following infection of these cells. Thus, macrophages appear fully permissive to productive HIV-1 replication while non-dividing (G0 T cells) restrict virus replication at a step which proceeds nuclear import of viral DNA. The requirement for T cell activation in productive HIV-1 replication has important implications for the relationship between immune activation and virus burden. It remains to be determined whether modulating the immune activation status of the infected individual may provide an opportunity for modulating virus burden and influencing disease course.
Asunto(s)
Síndrome de Inmunodeficiencia Adquirida/fisiopatología , VIH-1/fisiología , Replicación Viral , Síndrome de Inmunodeficiencia Adquirida/inmunología , Animales , Núcleo Celular/metabolismo , Humanos , Activación de Linfocitos , Mitosis/inmunología , Ácidos Nucleicos/metabolismo , Linfocitos T/inmunologíaAsunto(s)
Trastornos Linfoproliferativos/genética , Cromosoma X , Trasplante de Médula Ósea , Clonación Molecular , ADN/análisis , Femenino , Ligamiento Genético , Marcadores Genéticos , Herpesvirus Humano 4 , Humanos , Inmunoglobulinas/uso terapéutico , Inmunosupresores/uso terapéutico , Mononucleosis Infecciosa/genética , Cariotipificación , Trastornos Linfoproliferativos/diagnóstico , Trastornos Linfoproliferativos/inmunología , Trastornos Linfoproliferativos/terapia , Masculino , Mutación , FenotipoRESUMEN
Formation of large syncytia and rapid cell killing are characteristics of the Zairian human immunodeficiency virus type 1 isolate HIV-1-NDK, which is highly cytopathic for CD4+ lymphocytes in comparison with the HIV-1-LAV prototype. Chimeric viruses containing different combinations of HIV-1-NDK genetic determinants corresponding to the splice donor, the packaging signal, and the coding sequence of the p18gag protein together with the HIV-1-NDK EcoRI5278-XhoI8401 fragment were obtained by polymerase chain reaction-directed recombination. Phenotypic analysis of recombinant viruses indicated that 75 amino acids from the N-terminal part of HIV-1-NDK p18gag protein together with the HIV-1-NDK envelope glycoprotein are responsible for enhanced fusogenicity of HIV-1-NDK in CD4+ lymphocytes as well as for enhanced infectivity of HIV-1-NDK in some CD4- cells lines. The HIV-1-NDK splice donor/packaging sequence and the sequence encoding the gag protein p25 were not important for the variation observed in HIV-1 fusogenicity.
Asunto(s)
Productos del Gen gag/genética , Genes Virales , Infecciones por VIH/genética , VIH-1/patogenicidad , Proteínas Virales de Fusión/genética , Secuencia de Aminoácidos , Linfocitos T CD4-Positivos/microbiología , Fusión Celular/genética , República Democrática del Congo , Variación Genética , Infecciones por VIH/patología , VIH-1/genética , Humanos , Datos de Secuencia Molecular , Especificidad de Órganos , Proteínas Recombinantes , Especificidad de la Especie , Relación Estructura-Actividad , Virulencia , Replicación Viral/genética , Productos del Gen gag del Virus de la Inmunodeficiencia HumanaRESUMEN
In an attempt to clarify the chronological relationships between Epstein-Barr virus (EBV) infection, B cell immortalization and c-fgr activation, we evaluated for the presence of EBV-determined nuclear antigen (EBNA), cellular DNA synthesis and expression of c-fgr-specific RNA following infection of human peripheral blood lymphocytes with B95-8 EBV. High expression of c-fgr was observed prior to EBNA detection and cellular DNA synthesis in EBV-infected cells. These results suggest that activation of c-fgr is an essential event during the early phase of EBV immortalization.
Asunto(s)
Linfocitos B/microbiología , Herpesvirus Humano 4 , Proteínas Proto-Oncogénicas/metabolismo , Antígenos Virales/análisis , Linfocitos B/metabolismo , Replicación del ADN , Antígenos Nucleares del Virus de Epstein-Barr , Regulación de la Expresión Génica , Herpesvirus Humano 4/inmunología , Humanos , Proto-Oncogenes Mas , Familia-src QuinasasRESUMEN
Human immunodeficiency virus type 1 (HIV-1) prototype, HIV1 LAV, and a Zairian virus HIV1 NDK, an isolate highly cytopathic for CD4+ lymphocytes, were used to infect eleven different CD4 negative non-lymphoid human cell lines. Eight of the lines were derived from carcinomas wherein human papillomavirus was thought to have been etiologic. All these cell lines lacked CD4 receptor and CD4 specific mRNA. After cocultivation with sensitive CEM cells, HIV-1 LAV was rescued from six infected cell lines and HIV-1 NDK from nine. Shedding of free virus into the culture medium was observed in three cell lines infected by HIV-1 NDK and in only one cell line infected by HIV-1 LAV. The infectibility of CD4 negative cell lines indicates that both HIV-1 strains were able to use a CD4 independent mechanism to infect the cells; however, HIV-1 NDK showed the higher efficiency of infection. This virus was also able to overcome the intracellular block of viral reproduction. These results suggest that a broader spectrum of cell types of non-lymphoid origin lacking the CD4 receptor can serve as a viral reservoir. In some cases they are direct producers of infectious HIV-1 particles. This suggests, that in addition to immunosuppressive mechanisms, HIV-1 could play a more direct role in induction of neoplastic changes.
Asunto(s)
Antígenos CD4/análisis , VIH-1/patogenicidad , Replicación Viral/fisiología , VIH-1/clasificación , VIH-1/fisiología , Humanos , Papillomaviridae , Células Tumorales Cultivadas , Infecciones Tumorales por Virus/microbiologíaRESUMEN
Formation of large syncytia, rapid cell killing, and early onset of replication are characteristics of the highly cytopathic Zairian virus strain HIV1 NDK compared with the HIV1 LAV prototype. Recombinant provirus molecules derived from cloned infectious DNAs of HIV1 LAV and NDK were constructed by reciprocal exchange of genetic material using conserved restriction sites. Different regions of the HIV1 genome were responsible for variability of the direct single-cell cytotoxic and fusogenic effects. A minimal, provisionally defined portion of genetic information responsible for the higher cytotoxicity of HIV1 NDK compared to the HIV1 LAV prototype was localized in the fragment Spel1042/EcoRl4183, containing the 3'-terminal half of gag and a majority of the pol gene. This region also determined the rapid replication properties of HIV1 NDK. The increased fusogenic potential of HIV1 NDK was associated with the simultaneous presence of HIV1 NDK fragments BssHll255/Spel1042 and EcoRl5278/Xhol8401 which contained the splicing donor, packaging sequence, p18 gag protein, and the HIV env gene. The increase in the direct killing effect but not in the syncytium forming ability of HIV1 NDK correlated with the early onset of replication and rapid spread of HIV1 NDK in cell cultures. The HIV1 NDK fragments BssHll/Spel and EcoRl/Xhol were by themselves necessary but not sufficient to induce formation of large syncytia.
Asunto(s)
Efecto Citopatogénico Viral , VIH-1/patogenicidad , Muerte Celular , Línea Celular , Quimera , ADN Recombinante , ADN Viral/genética , Genes gag , Genes pol , Células Gigantes , VIH-1/genética , VIH-1/aislamiento & purificación , Humanos , Fenotipo , Replicación ViralRESUMEN
Nine oligopeptides corresponding to segments of different open reading frame (ORF) proteins of human papillomavirus (HPV) 6b and HPV-16 were prepared and tested for reactivity with human sera in enzyme-immunoassay (ELISA). Of these only heptadecapeptide derived from L2 ORF of HPV-6b, and encoded also by L2 ORF of HPV 11, was reactive with some human sera. Over 400 human sera of different origin were tested for the presence of antibody to this antigen. While less than 15% of sera from healthy subjects or cervical carcinoma patients were found antibody positive, sera from the majority of condylomata accuminata (CA) patients were reactive. The antibody titres varied from 1:10 (initial serum dilution) to 1:80; in this respect there was no marked difference between sera from CA patients and the other subjects. The prevalence of antibody was higher among promiscuous than nonpromiscuous women. This is in line with the assumption that sexual intercourse is the most important route of HPV 6 and 11 transmission.
Asunto(s)
Anticuerpos Antivirales/sangre , Papillomaviridae/inmunología , Fragmentos de Péptidos/inmunología , Proteínas Virales/inmunología , Secuencia de Aminoácidos , Antígenos Virales/química , Condiloma Acuminado/inmunología , Epítopos/química , Femenino , Humanos , Datos de Secuencia Molecular , Papillomaviridae/clasificación , Fragmentos de Péptidos/química , Infecciones Tumorales por Virus/inmunología , Infecciones Tumorales por Virus/transmisión , Neoplasias del Cuello Uterino/inmunología , Proteínas Virales/químicaRESUMEN
Reactivated Epstein-Barr virus infection associated with hepatitis appeared in a liver transplant patient receiving monoclonal OKT-3 antibody for rejection. The histologic findings in liver biopsy specimens characteristic of allograft rejection were observed prior to and during the initial phase of antirejection therapy. However, failure of a complete response to antirejection therapy promoted rebiopsy. The specimen showed portal infiltrates composed predominantly of plasma cells and immunoblasts. The presumptive diagnosis of Epstein-Barr virus hepatitis was confirmed by staining frozen liver tissue for Epstein-Barr virus nuclear-associated antigen. OKT-3 therapy was discontinued, and cyclosporine and steroid doses were reduced. Gradually, clinical features, serum aminotransferase and bilirubin levels, and the portal lymphoid infiltrate resolved. Epstein-Barr virus serology showed an increase in convalescent titers IgG-antiviral capsid antigen, and Epstein-Barr virus nuclear-associated antigen. The histologic, clinical, and laboratory features supporting the diagnosis of Epstein-Barr virus hepatitis in a liver transplant patient are presented and discussed. This diagnosis guided appropriate therapy.