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1.
Vox Sang ; 91(1): 34-40, 2006 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-16756599

RESUMEN

BACKGROUND AND OBJECTIVES: Transmissible spongiform encephalopathies (TSEs) are fatal neurodegenerative diseases caused by aberrantly folded cellular proteins (PrP(Sc); prions) that are generally resistant to conventional pathogen-inactivation techniques. To ensure effective decontamination and inactivation of prions that could be present in source material, we investigated critical factors that influence prion inactivation by NaOH. MATERIALS AND METHODS: A decrease in prion infectivity correlates with the disappearance of the protease-resistant core of PrPSc (PrPRES) observed in biochemical assays. To model prion inactivation, hamster scrapie (strain 263K) brain homogenate (SBH) was incubated for specific periods of time in 0.1 m NaOH at 4 or 18 degrees C, with or without detergent. Neutralized samples were subjected to limited digestion with proteinase K (PK) and then analysed using an endpoint dilution western blot assay and antibody 3F4. Structural changes in prions exposed to NaOH were examined using differential immunoprecipitation. RESULTS: Treatment of SBH with 0.1 m NaOH for 15 min, in the absence of detergent, at 4 and 18 degrees C caused a reduction in the PrP(RES) signal of 3.5 and 4.0 log10 units, respectively, with some residual signal remaining. The presence of the detergent sarkosyl during a 60-min incubation in NaOH further enhanced PrPRES reduction to > or = 4.5 log10 units (i.e. below the limit of detection). NaOH treatment induced conformational changes in PrP that resulted in the exposure of a hidden epitope and enabled prion immunoprecipitation by antibody 3F4. CONCLUSIONS: The use of NaOH can effectively reduce prion levels in an in vitro inactivation assay. After pretreatment of SBH with detergent, NaOH completely eliminates the PrPRES signal. Detergent may liberate lipid membrane-protected PrPSc to improve access to NaOH, which can then inactivate PrPSc by altering its structure. In cases of unidentified exposure to PrPSc during manufacturing, sanitizing procedures combining the use of detergent and NaOH may help to ensure minimal levels of contamination carryover in products.


Asunto(s)
Bioensayo , Descontaminación , Endopeptidasa K/química , Proteínas PrPSc/química , Enfermedades por Prión/prevención & control , Sarcosina/análogos & derivados , Hidróxido de Sodio/química , Animales , Cricetinae , Proteínas PrPSc/patogenicidad , Sarcosina/química
2.
Biologicals ; 34(4): 281-8, 2006 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-16500114

RESUMEN

This study summarises the biochemical and functional properties of a new generation plasma-derived, double virus inactivated von Willebrand Factor/Factor VIII (VWF/FVIII) concentrate, Wilate, targeted for the treatment of both von Willebrand disease (VWD) and haemophilia A. The manufacturing process comprises two chromatographic steps based on different performance principles, ensuring a high purity of the concentrate (mean specific activity in 15 consecutive production batches: 122 IU FVIII:C/mg total protein) and, thus, minimising the administered protein load to the patient (specification: < or = 15 mg total protein per 900 IU Wilate). The optimised solvent/detergent (S/D) treatment and prolonged terminal dry-heat (PermaHeat) treatment of the lyophilised product at a specified residual moisture (RM) provide two mechanistically independent, effective and robust virus inactivation procedures for enveloped viruses and one step for non-enveloped viruses. These process steps are aggressive enough to inactivate viruses efficiently, but yet gentle enough to maintain the structural integrity and function of the VWF and FVIII molecules, as proven by state-of-the-art assays covering the diverse features of importance. The VWF multimeric pattern is close to the one displayed by normal plasma, with a consistent content of more than 10 multimers, but a relatively lower portion of the very high multimers. The multimeric triplet structure is normal, underlining the gentle and effective manufacturing process, which does not require the addition of protein stabilisers at any step. The balanced activity ratio of VWF to FVIII is close to that of plasma from healthy subjects, rendering Wilate suitable also for the safe and effective treatment of patients with VWD.


Asunto(s)
Factor VIII/aislamiento & purificación , Factor VIII/fisiología , VIH-1/fisiología , Inactivación de Virus , Factor de von Willebrand/aislamiento & purificación , Factor de von Willebrand/fisiología , Proteínas Sanguíneas/fisiología , Factor VIII/química , VIH-1/aislamiento & purificación , Humanos , Seguridad , Factor de von Willebrand/química
3.
Biologicals ; 33(2): 95-9, 2005 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-15939287

RESUMEN

SARS-coronavirus (SARS-CoV) is a newly emerged, highly pathogenic agent that caused over 8000 human infections with nearly 800 deaths between November 2002 and September 2003. While direct person-to-person transmission via respiratory droplets accounted for most cases, other modes have not been ruled out. SARS-CoV viraemia does not seem to reach high titres, however, it has to be excluded that virus transmission may occur via blood transfusion or application of therapeutic plasma products, e.g. fresh-frozen plasma or single components derived thereof. Manufacturing processes of all plasma derivatives are required to comprise dedicated virus inactivation/removal steps. Treatment with a mixture of solvent and detergent (SD) has successfully been applied to inactivate the most members of the transfusion-relevant viruses without affecting therapeutic properties of the products. The SD treatment irreversibly disrupts the lipid envelope of viruses such as HIV, HBV, HCV, HGV and CMV. In this study we evaluated the manufacturing process of an immunoglobulin preparation (OCTAGAM, manufactured by Octapharma Pharmazeutika Produktionsges.m.b.H., Vienna, Austria) for its capacity to inactivate the SARS-CoV. Our results demonstrate that SARS-CoV was completely inactivated below the limit of detection. This was found to occur within 1 min of SD treatment.


Asunto(s)
Detergentes/farmacología , Inmunoglobulinas , Coronavirus Relacionado al Síndrome Respiratorio Agudo Severo/efectos de los fármacos , Solventes/farmacología , Inactivación de Virus , Humanos
4.
Thromb Res ; 100(5): 433-41, 2000 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-11150587

RESUMEN

The paper describes the production of a prothrombin complex concentrate (PCC) with high virus safety and a well-balanced content of vitamin K-dependent clotting factors and inhibitors. Solid-phase extraction is followed in a second step by optimized anion exchange chromatography using a radial column. A step for virus removal by nanofiltration is introduced in addition to the solvent/detergent step. By speeding up the chromatographic step, the period of time required for production is reduced considerably. The activities of the four vitamin K-dependent clotting factors II, VII, IX and X are in ratios of about 1:1:1:1. Protein C, Protein S, and Protein Z are also present in therapeutically effective concentrations. The product shows no thrombogenicity, in either in vivo nor in vitro models. Clinical investigations show that the PCC is a safe and efficient preparation for the substitutive treatment of FIX or FVII in patients suffering from the respective deficiencies. All bleeding episodes have been efficiently controlled with relatively low doses of the concentrate. The surgical procedures have been conducted without any problems in severely FIX and FVIII deficient patients.


Asunto(s)
Protrombina/aislamiento & purificación , Animales , Humanos , Protrombina/farmacología , Protrombina/uso terapéutico , Ratas , Trombosis/prevención & control
5.
Vox Sang ; 74 Suppl 1: 207-12, 1998.
Artículo en Inglés | MEDLINE | ID: mdl-9789530

RESUMEN

OCTAPLAS is a cell-free standardized blood group specific human coagulation active plasma for transfusion. The viral safety is mainly based on the treatment with solvent/detergent. SD is known to irreversibly inactivate the lipid enveloped viruses including HIV 1 + 2, HBV and HCV and has been recommended both by European guidelines and the FDA. The potential limitation of each inactivation method should be validated according to the current EU-guidelines CPMP/BWP/268/95 and CPMP/BWP/269/95. Our studies demonstrate that the SD method inactivates lipid enveloped viruses within a few minutes to below the limit of detection. The concentration of the SD reagents as well as several other process parameters chosen for the virus inactivation step of plasma pools of different protein and lipid composition result in a high safety margin towards the clinically relevant viruses.


Asunto(s)
Detergentes , Intercambio Plasmático/efectos adversos , Plasma/virología , Solventes , Esterilización/métodos , Patógenos Transmitidos por la Sangre , Guías como Asunto , Humanos , Retroviridae/crecimiento & desarrollo , Seguridad , Virosis/prevención & control , Virosis/transmisión
6.
J Chromatogr B Biomed Sci Appl ; 694(2): 253-69, 1997 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-9252039

RESUMEN

Product development and process validation are shown in the case of several products obtained from human plasma. These are virus-inactivated plasma, intravenous immunoglobulins and the clotting factors VIII and IX. Different analytical methods are presented, which are used for product control and in-process control. For the production of virus-inactivated human plasma a down-scale protocol is presented, allowing a simulation of the production on a laboratory scale. Virus validation has shown that the reduction of transfusion-relevant viruses in the process was higher than six log steps. Determination of leachables from the RP-column, which was used in this production, proved that they appear in the final product in quantities below the detection limits only. It was also shown that the chemicals used for virus inactivation could be quantitatively removed from the product. For the isolation of other products, here intravenous gamma globulins and the clotting factors VIII and IX, similar validation steps had to be taken. In the case of clotting factor VIII the following data were determined, the reduction of viruses, the amount of leachables from the column, the residues of chemicals from the solvent/detergent treatment for virus inactivation. Virus reduction was successfully performed as well as the removal of chemicals used for virus inactivation. The amount of leachables from the columns used for chromatographic purification was found to be far below the permissible levels.


Asunto(s)
Productos Biológicos/aislamiento & purificación , Proteínas Sanguíneas/aislamiento & purificación , Plasma/virología , Cromatografía de Afinidad , Cromatografía por Intercambio Iónico , Detergentes , Contaminación de Medicamentos , Humanos , Octoxinol , Reproducibilidad de los Resultados , Seguridad , Virosis/transmisión , Virus/aislamiento & purificación
7.
Clin Exp Rheumatol ; 14 Suppl 15: S47-52, 1996.
Artículo en Inglés | MEDLINE | ID: mdl-8828948

RESUMEN

OBJECTIVE: A validation study of the viral safety of a new polyvalent intravenous immunoglobulin (OCTAGAM) according to EU-guideline III/8115/89-EN and the requirements of the Federal Agency for Sera and Vaccines in Germany was undertaken in May 1994. The following processing steps were analyzed: Cohn-Oncley fractionation, solvent/detergent (SD) treatment, pH 4 exposure, storage of the final product at low pH and immune neutralisation. METHODS: The following virus reduction factors were obtained: Cohn-Oncley fractionation: HIV-1 > 5.50; sindbis virus > 6.36; pseudorabies virus > 7.28; coxsackievirus-B6 2.70; poliovirus-1 > 3.80; SV40 > 5.51. Solvent/Detergent treatment: HIV-1 > 6.03; sindbis virus > 7.80; pseudorabies virus > 8.38. pH 4 exposure: HIV-1 > 8.60; sindbis virus > 8.94; pseudorabies virus > 5.95; coxsackievirus-B6 2.72; SV40 1.15. Immune neutralisation: coxsackievirus-B6 > 4.98, polio-virus-1 > 5.14, HAV > 3.44, HSV-1 > 5.92. The following virus reduction factors were calculated for the final product: HIV-1 > 20.13; sindbis virus > 23.10; pseudorabies virus > 21.61; coxsackievirus-B6 > 10.4; poliovirus-1: > 8.94; HAV > 3.44; SV40 > 6.66. CONCLUSION: The results of our validation studies demonstrated that in addition to Cohn fractionation and immune neutralization, the two additional steps of solvent/detergent treatment and pH 4 exposure, mainly contribute to the safety of OCTAGAM with respect to both enveloped and non-enveloped viruses.


Asunto(s)
Productos Biológicos/normas , Sangre/virología , Inmunoglobulinas Intravenosas/normas , Virosis/prevención & control , Detergentes , Alemania , Agencias Gubernamentales/normas , Guías como Asunto , VIH-1/efectos de los fármacos , Humanos , Tamizaje Masivo , Control de Calidad , Reproducibilidad de los Resultados , Virus Sindbis/efectos de los fármacos , Virosis/transmisión
8.
J Med Virol ; 48(4): 360-6, 1996 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-8699169

RESUMEN

The inactivation of both transfusion-relevant and model viruses by modified pasteurisation (10 hours at 63 degrees C in solution) has been evaluated following the established guidelines of the EU CPMP Ad Hoc Working Party on Biotechnology/Pharmacy. This heat treatment was introduced into the manufacturing process of OCTAVI, a very high purity factor VIII concentrate stabilized only by von Willebrand factor, in the presence of a proprietary mixture of low molecular weight stabilizers. Both enveloped (human immunodeficiency virus, Sindbis virus, herpes simplex virus, pseudorabies virus) and nonenveloped viruses (poliovirus, Coxsackievirus, hepatitis A virus) were inactivated by this heating step by more than 4.7 log10. The combination of the solvent/detergent step used in the manufacture of OCTAVI with this modified pasteurization leads to a double virus-inactivated factor VIII concentrate (OCTATE) with a viral safety distinctly superior to monoinactivated products.


Asunto(s)
Contaminación de Medicamentos , Factor VIII , Calefacción , Esterilización , Virus , Animales , Línea Celular , Química Farmacéutica/normas , Seguridad de Productos para el Consumidor , Detergentes , Humanos
9.
J Pept Sci ; 1(5): 303-10, 1995.
Artículo en Inglés | MEDLINE | ID: mdl-9223009

RESUMEN

Small enkephalin-related peptides containing a 1-adamantanamine moiety coupled through an amide linkage at the C-terminus were synthesized. Several of the compounds showed high mu opioid activity and mu receptor selectivity. The new adamantanamine derivatives were also examined for antiviral activity against HIV-1 in a cell culture system. Some of them inhibited syncytia formation even when the antigen assay gave evidence for viral replication.


Asunto(s)
Adamantano/análogos & derivados , Oligopéptidos/síntesis química , Oligopéptidos/farmacología , Adamantano/síntesis química , Adamantano/farmacología , Secuencia de Aminoácidos , Animales , Antivirales/síntesis química , Antivirales/química , Antivirales/farmacología , Encefalinas/síntesis química , Encefalinas/química , Encefalinas/farmacología , Cobayas , VIH-1/efectos de los fármacos , Humanos , Íleon/efectos de los fármacos , Técnicas In Vitro , Masculino , Ratones , Estructura Molecular , Oligopéptidos/química , Receptores Opioides delta/efectos de los fármacos , Receptores Opioides mu/efectos de los fármacos , Conducto Deferente/efectos de los fármacos
10.
J Chromatogr B Biomed Appl ; 669(2): 187-96, 1995 Jul 21.
Artículo en Inglés | MEDLINE | ID: mdl-7581895

RESUMEN

A virus removal system based on tangential flow filtration was introduced into a Factor IX production process. Beside the intended virus reduction potency of filter membranes, an additional purification effect could be achieved. This purification effect was evaluated in detail by means of sodium dodecyl sulphate-polyacrylamide gel electrophoresis and size-exclusion HPLC. High-molecular-mass impurities were retained by the membrane, thus increasing the specific activity of the product.


Asunto(s)
Patógenos Transmitidos por la Sangre/aislamiento & purificación , Factor IX/aislamiento & purificación , Ultrafiltración/métodos , Virus/aislamiento & purificación , Cromatografía en Gel , Cromatografía por Intercambio Iónico , Electroforesis en Gel de Poliacrilamida , Humanos , Inmunodifusión
11.
Blood Coagul Fibrinolysis ; 6 Suppl 2: S48-54, 1995 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-7495968

RESUMEN

The inactivation of both transfusion-relevant and model viruses by modified pasteurization has been evaluated following the established guidelines of the European Union Committee for Proprietary Medical Products Ad Hoc Working Party on Biotechnology/Pharmacy. This heat treatment in solution for 10 h at 63 degrees C was introduced into the manufacturing process of OCTAVI, a very high purity factor VIII concentrate stabilized by von Willebrand factor. It could be demonstrated that both enveloped (human immunodeficiency virus, herpes simplex virus, pseudorabies virus) and non-enveloped viruses (poliovirus, coxsackievirus, hepatitis A virus) were inactivated by this heating step with an efficacy of greater than 4.5 log10 TCID50. The combination of the solvent/detergent step already used in the manufacture with this modified pasteurization leads to a double virus-inactivated factor VIII concentrate (OCTAVI SDPlus) with a viral safety distinctly superior to monoinactivated products.


Asunto(s)
Antivirales , Bancos de Sangre/normas , Donantes de Sangre , Factor VIII/aislamiento & purificación , Reacción a la Transfusión , Detergentes , Unión Europea , Guías como Asunto , Calor , Humanos , Reproducibilidad de los Resultados , Solventes
12.
Immun Infekt ; 21(4): 106-10, 1993 Aug.
Artículo en Alemán | MEDLINE | ID: mdl-8370592

RESUMEN

Due to the closer virus-host interactions viral diseases are more difficult to control by drugs than most of the bacterial infections. Moreover, the search for antiviral compounds against HIV is an exceptional challenge. The enormous genetic and biological variability, the life-long persistence and the invasion of the brain are only some of the aspects which complicate a fast solution. In principal there are three different strategies to develop new chemotherapeutics. Most of the drugs so far tested in clinical trials were identified by routine screening, others were modified by specific chemical synthesis. After the three-dimensional structure of some HIV proteins became known, rational drug design by computer modeling resulted in compounds exhibiting excellent anti-HIV activity in vitro. The reverse transcriptase inhibitor AZT has been used for HIV-infected individuals for several years. However, side effects and the development of AZT-resistant virus strains force to combine AZT with other drugs and to develop additional lead compounds.


Asunto(s)
Antivirales , Infecciones por VIH/tratamiento farmacológico , Humanos
13.
Biochim Biophys Acta ; 1149(1): 29-39, 1993 Jun 18.
Artículo en Inglés | MEDLINE | ID: mdl-8391319

RESUMEN

Synthetic tripalmitoyl-S-glycerylcysteinyl (Pam3Cys) peptides are derived from the N-terminal part of bacterial lipoprotein and constitute polyclonal B-lymphocyte and macrophage activators. In order to elucidate the primary events of leukocyte activation, we investigated the biophysical interaction of lipopeptides containing spin labels or fluorescent markers with phosphatidylcholine vesicles or immune cells. Utilizing fluorescence microscopy and FACS analysis we found, that the surface of cells, after incubation with a fluorescein-labelled lipopeptide, was highly fluorescent. In addition, capping and patching was observed. Furthermore, fluorescence quenching experiments and electron paramagnetic resonance studies using vesicles incubated with lipopeptides suggested, that the peptide moiety and other more polar molecules linked to the lipo-amino acid are exposed to the hydrophilic compartment. These results show that in lipopeptide conjugates the Pam3Cys moiety acts as an efficient membrane anchor for molecules covalently coupled to it. The sequestering of the fatty-acid chains of the lipopeptide within the membrane is an early step of interaction, which might induce the uptake of the lipopeptide into the cell and the stimulation of immunocompetent cells.


Asunto(s)
Linfocitos B/metabolismo , Proteínas de la Membrana Bacteriana Externa/farmacología , Proteínas Portadoras/farmacología , Membrana Celular/metabolismo , Proteínas de Escherichia coli , Mitógenos/farmacología , Péptidos/farmacología , Secuencia de Aminoácidos , Linfocitos B/efectos de los fármacos , Proteínas de la Membrana Bacteriana Externa/química , Proteínas Portadoras/química , Cisteína/análogos & derivados , Cisteína/farmacología , Espectroscopía de Resonancia por Spin del Electrón , Ácidos Grasos/metabolismo , Citometría de Flujo , Fluoresceína-5-Isotiocianato , Modelos Moleculares , Datos de Secuencia Molecular , Péptidos/metabolismo , Sonicación , Células Tumorales Cultivadas
14.
Behring Inst Mitt ; (89): 74-80, 1991 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-1930105

RESUMEN

Sequential virus isolates from an HIV-1-infected woman treated orally with 3'-azido-3'-deoxythymidine (AZT) for over two years showed a 10-fold reduced sensitivity for AZT after 8 months and a 100-fold resistance after 24-32 months of drug therapy. These AZT-resistant mutants were totally sensitive in vitro to other reverse transcriptase (RT)-inhibitors like the AZT-analogue 3'-fluoro-3'-deoxythymidine (FdT) or the chemically less related nucleoside analogue 2',3'-dideoxycytosine (ddC). Even the benzodiazepin derivative 4,5,6,7-tetrahydro-5-methyl-6-(3-methyl-2-butenyl)-imidazo [4,5,1-jk][1,4]-benzodiazepin-2(1H)-thione (TIBO), a new drug specific for HIV-1 RT, was inhibitory for these virus strains. Moreover, compounds with different modes of action, e.g. polysulfated polyxylan, exhibited full antiviral activity as well. Thus, AZT resistance seems to be highly specific and should allow to develop further drugs to be used when AZT resistance has emerged. 5.9 kb fragments of the 5'-genomic halves of these sequential HIV-isolates were amplified by PCR and cloned. DNA sequence analysis revealed that the RT gene of the two highly AZT-resistant isolates carried two of the mutations described by Larder et al. [Science 246, (1989)], the Lys 70----Arg and the Thr 215----Tyr transitions. The isolate obtained after 32 months of AZT-therapy in addition contained a third mutation at position 67 (Asp----Asn); in contrast to Larder's report, no mutation was found at position 219. Thus, although these virus isolates showed at least a 100-fold reduced susceptibility for AZT in vitro, the four mutations postulated to be relevant for highly resistant strains were only partially confirmed.


Asunto(s)
Farmacorresistencia Microbiana/genética , VIH/genética , Replicación Viral/efectos de los fármacos , Zidovudina/farmacología , Secuencia de Aminoácidos , Antivirales/farmacología , Secuencia de Bases , Células Cultivadas , Clonación Molecular , ADN Viral/genética , VIH/efectos de los fármacos , VIH/fisiología , Humanos , Monocitos , Reacción en Cadena de la Polimerasa
15.
Infection ; 19 Suppl 2: S77-82, 1991.
Artículo en Inglés | MEDLINE | ID: mdl-1673119

RESUMEN

In order to find parameters which allow the assessment of the clinical state of HIV patients with or without antiviral therapy, viral cultures on lymphocytes and monocytes/macrophages, CD4-cell counts, HIV antigen, beta 2-microglobulin and serum cholesterol were evaluated for their predictive value. As had been shown previously for lymphocytes, the efficiency of viral isolation on macrophages also depends on the disease stage (CDC) of the patients and thus has a high predictive value. A multivariant discriminant analysis showed that the combination of beta 2-microglobulin, viral antigen, CD4+ cell count and HDL cholesterol predicted the outcome of viral cultures with 80% accuracy. While viral antigen, CD4+ cell counts and beta 2-microglobulin had been known, HDL cholesterol deserves further evaluation as prognostic parameter. The analysis of HIV derived from patients with AZT showed a 20-200-fold in vitro drug resistance after seven to 24 months of therapy. DNA sequence determination of such strains isolated from AZT patients over time showed only two of the amino acid exchanges described in the literature for resistant strains and an additional Val60-Ile transition after 32 months of therapy.


Asunto(s)
Linfocitos T CD4-Positivos/microbiología , HDL-Colesterol/sangre , Infecciones por VIH/tratamiento farmacológico , VIH/aislamiento & purificación , Zidovudina/uso terapéutico , Microglobulina beta-2/análisis , Células Cultivadas , Farmacorresistencia Microbiana , Estudios de Evaluación como Asunto , Antígenos VIH/sangre , Infecciones por VIH/sangre , Infecciones por VIH/microbiología , Humanos , Recuento de Leucocitos , Macrófagos/microbiología , Monocitos/microbiología , Factores de Tiempo
16.
Med Microbiol Immunol ; 179(6): 307-21, 1990.
Artículo en Inglés | MEDLINE | ID: mdl-1965549

RESUMEN

The polysulfated polyxylan HOE/BAY946, which has been tested in two pilot studies in ARC/AIDS patients and in asymptomatic HIV carries in Germany, was believed to act by inhibiting virus attachment to the cell. However, the drug was also found to reduce the amount of HIV particles released from infected peripheral blood mononuclear cells (PBMC) in vitro. Furthermore, preincubation of PBMC with the drug led to a partial inhibition of a following HIV infection, suggesting that the drug also affects virus entry. Electron Paramagnetic Resonance (EPR) measurements on uninfected human lymphocytes using 5-proxyl-nonane as spin label demonstrated smaller hyperfine coupling constant (aN) values in the presence of HOE/BAY946 or dextran sulfate 5000. Accordingly, h-1p/h-1H ratios were decreased, indicating increased plasma membrane hydrophobicity and a membrane-stabilizing effect of the drugs. Culture of the chronically HIV-infected monocytic cell line U937/HIV-2D194 in the presence of HOE/BAY946 specifically and drastically reduced the release of virions and the intracellular synthesis of viral proteins as determined by radioimmunoprecipitation and reverse transcriptase assays. In conclusion, although the EPR studies showed a physico-chemical effect on membrane polarity, HOE/BAY946 and dextran sulfate clearly affect processes beyond the cell membrane. Thus, in contrast to previous reports suggesting that polysulfated sugars affect HIV only by inhibiting virus binding to uninfected cells, they clearly inhibit HIV in infected cells as well and appear to have a pleiotropic mode of action. Such drugs may be less likely to result in viral resistance after prolonged application than substances acting only on one step in the life cycle of the virus.


Asunto(s)
Antivirales/farmacología , VIH/efectos de los fármacos , Linfocitos/microbiología , Polisacáridos/farmacología , Proteínas Virales/biosíntesis , Línea Celular , Membrana Celular/efectos de los fármacos , Membrana Celular/metabolismo , Espectroscopía de Resonancia por Spin del Electrón , VIH/crecimiento & desarrollo , VIH/metabolismo , Infecciones por VIH/tratamiento farmacológico , Humanos , Linfocitos/efectos de los fármacos , Poliéster Pentosan Sulfúrico , Solubilidad , Virión/efectos de los fármacos , Virión/crecimiento & desarrollo , Virión/metabolismo , Replicación Viral
17.
Lung ; 168 Suppl: 707-15, 1990.
Artículo en Inglés | MEDLINE | ID: mdl-2117181

RESUMEN

Bacterial extracts obtained from pathogenic strains occurring in lung infections (Broncho Vaxom) or urogenital infections (Urovaxom) as well as defined surface components of Gram-negative bacteria purified from bacteria or obtained by chemical synthesis were tested for their immunomodulatory properties in a murine system. The bacterial extracts were able to act as immunogens inducing an antigen-specific response. Both the bacterial extracts and the purified bacterial cell wall components constituted polyclonal activators of murine splenic B cells, as demonstrated by proliferation assays measuring the incorporation of [3H]thymidine into DNA. They were also able to act as immunoadjuvants increasing the SRBC and the BSA-TNP specific immune response, and could induce tumor cytotoxicity in bone marrow-derived macrophages. The results show that bacterial extracts and defined bacterial surface components constitute immunogens as well as immunomodulators in vitro and in vivo.


Asunto(s)
Adyuvantes Inmunológicos , Antígenos Bacterianos , Linfocitos B , Bacterias , Proteínas de la Membrana Bacteriana Externa , Activación de Linfocitos , Activación de Macrófagos , Animales , Ratones , Adyuvantes Inmunológicos/administración & dosificación , Linfocitos B/inmunología , Proteínas de la Membrana Bacteriana Externa/inmunología , Citotoxicidad Inmunológica/inmunología , Bacterias Gramnegativas/inmunología , Activación de Linfocitos/inmunología , Activación de Macrófagos/inmunología , Ratones Endogámicos BALB C , Péptidos/inmunología
18.
Res Immunol ; 140(7): 685-95, 1989 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-2595080

RESUMEN

Membrane proteins from murine lymphoblasts enriched by the Triton-X114 procedure were analysed by 2-dimensional gel electrophoresis to reveal proteins differentially expressed in mitogen-reactive subpopulations of B cells. The protein patterns from C57BL/6 normal and nude mice and from the B10.Sc.Cr LPS-non-responder strain, activated with lipopolysaccharide (LPS) or an analogue of lipoprotein, were virtually identical when run under strictly parallel conditions. These experiments raise the question as to whether mitogen receptors, serologically and functionally found to be membrane-bound, do exist as membrane proteins.


Asunto(s)
Linfocitos B/análisis , Lipopolisacáridos/farmacología , Lipoproteínas/farmacología , Proteínas de la Membrana/análisis , Animales , Femenino , Lipopéptidos , Activación de Linfocitos , Masculino , Ratones , Ratones Endogámicos C57BL , Oligopéptidos/farmacología
19.
Proc Natl Acad Sci U S A ; 86(7): 2383-7, 1989 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-2467304

RESUMEN

Human immunodeficiency virus type 2 (HIV-2)-related viruses were isolated from a Gambian dying of exclusively neurological disease (HIV-2D194) and from an asymptomatic Ghanian (HIV-2D205). Both strains exhibited properties of HIV-1 biological subtype c: they grew slowly and induced few or no syncytia but eventually produced high levels of particle-associated reverse transcriptase in cultures of fresh peripheral blood lymphocytes, and they established stable infection of T-lymphoma (HUT-78) and monocytic (U937) cell lines. Each produced even higher levels of reverse transcriptase when fresh human monocytes/macrophages were used as target cells. The viruses were molecularly cloned after a single passage in culture, in order to minimize in vitro selection of subtypes present in vivo. Restriction-site analysis showed heterogeneity within each isolate. Nucleotide sequence analysis of a portion of the HIV-2D194 genome revealed that it is a member of the prototypic HIV-2 family, displaying 13% divergence versus HIV-2ROD and HIV-2NIHZ, as compared to 9% divergence between HIV-2ROD and HIV-2NIHZ. In contrast, HIV-2D205 is the most highly divergent HIV-2 strain yet described: it is equidistant in relation between the known HIV-2 strains and the simian immunodeficiency virus isolates from rhesus macaque monkeys (23-25% divergence).


Asunto(s)
ADN Viral/genética , VIH-2/genética , Macrófagos/microbiología , Replicación Viral , Síndrome de Inmunodeficiencia Adquirida/complicaciones , Síndrome de Inmunodeficiencia Adquirida/microbiología , Células Cultivadas , Clonación Molecular , Gambia , Genes Virales , VIH-2/aislamiento & purificación , VIH-2/fisiología , Humanos , Linfocitos/microbiología , Enfermedades del Sistema Nervioso/etiología , ADN Polimerasa Dirigida por ARN/metabolismo , Mapeo Restrictivo
20.
J Virol Methods ; 22(2-3): 173-82, 1988 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-2464607

RESUMEN

A novel immunoassay technique using synthetic lipopeptide (Pam3Cys-Ser) linked to immunodominant peptide domains of HIV-1 and HIV-2 envelope proteins as an antigen adsorbent has been developed. Attachment of peptides to microtiter plates can be considerably improved with this method by employing the hydrophobic properties of lipopeptide. From the sera of 121 HIV-1 infected patients 117 reacted with Pam3Cys-Ser-[HIV-1(598-609)cyclic disulfide]. Five of 5 HIV-2 positive sera were positive with Pam3Cys-Ser-[HIV-2(593-603)cyclic disulfide]. Control sera failed to react with these conjugates.


Asunto(s)
Síndrome de Inmunodeficiencia Adquirida/diagnóstico , Infecciones por Deltaretrovirus/diagnóstico , Ensayo de Inmunoadsorción Enzimática , VIH-1 , VIH-2 , Epítopos , Antígenos VIH , Humanos , Péptidos Cíclicos , Proteínas de los Retroviridae/inmunología , Programas Informáticos , Proteínas del Envoltorio Viral/inmunología
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