Validation of model virus removal and inactivation capacity of an erythropoietin purification process.

Human erythropoietin (hEpo) production requires mammalian cells able to make complex post-translational modifications to guaranty its biological activity. As mammalian cell can be reservoir of pathogenic viruses and several animal origin components are usually used in the cultivation of mammalian cells, hEpo contamination with viruses is something of great concern. As consequence, this study investigated the viral removal and inactivation capacity of a recombinant-hEpo (rec-hEpo) purification process. Canine parvovirus, Human poliovirus type-2, Bovine viral diarrhea virus and Human immunodeficiency virus type-1 were used for measuring process viral removal and inactivation capacities. In conclusion, this study corroborated that the assessed rec-hEpo purification process has enough capacity (5.0-19.4 Logs) for removing and inactivating these model viruses and sodium hydroxide demonstrated to be a robust sanitization solution for chromatography columns (5.0 (PV-2)-6.7 (CPV) Logs).

[Ultrastructural aspects of the HIV-1 infection in human placental villi with zidovudine treatment]. / Aspectos ultraestructurales de la infección por VIH-1 en vellosidades placentarias humanas tratadas con zidovudina.

BACKGROUND: HIV patients with normal placental villi can suffer degenerative changes, the hormones that maintain pregnancy (HCG and progesterone) are diminishing, the pH of blood and oxygen tensions lower. OBJECTIVE: To demonstrate ultrastructural degenerative changes in placental villi at term of pregnant women infected by HIV-1 with zidovudine treatment. MATERIAL AND METHOD: Four placentas at term from seropositive mothers were analyzed; three specimens of each one were processed with conventional transmission electron microscopy. The results were compared with four control cases. RESULTS: Particles belonging to the viral structure associated with the microvilli of the syncytium and cytoplasmic regions were found. Were observed: interruptions of syncytial plasma membrane, syncytial edema; loss of ribosomes at level of RER, disappearance of mitochondria, Golgi complex, RER, lysosomes and cytoplasmic filaments, dissolution of hyaloplasmic matrix, filopodiums of syncytial membrane, aggregated nuclear heterochromatin and dilated perinuclear cistern. Macrophagues had numerous particles into cytoplasm, probably pertaining to electron dense material contained in the viral nucleocapsid, also observed in the stromal region close to the endothelium of the villus. Some myofibroblasts were detected suffering a process of cellular death with cariorexis event. CONCLUSIONS: These changes indicate that the cytopathic effect spreads from peripheral syncytium to stromal zone suggesting that the damaged placental barrier don't have the better conditions for the transmission of gases, nutrients and metabolites toward fetal circulation.

Estado actual de la evaluación y manejo del paciente HIV positivo con métodos de laboratorio / Current state of evaluation an management of positive HIV patient with laboratory methods

A más de una década de la descripción de los retrovirus, del surgimiento del síndrome de inmunodeficiencia adquirida, del aislamiento y demostración del papel etiopatogénico de los virus de inumnodeficiencia humana (HIV I y 2), se ha desarrollado toda una gama de elementos diagnósticos y terapéuticos, siendo necesario establecer lineamientos para facilitar su comprensión y manejo; en la actualidad el diagnóstico se lleva a cabo con diversos procedimientos inmunológicos, citométricos, virológicos, y más recientemente de biología molecular. En este trabajo se propone una estrategia para el posible abordaje diangóstico dependiendo de cuatro situaciones clínicas: I) Individuo con riesgo de infección por HIV, 2) Adulto HIV positivo con o sin manifestaciones de SIDA, 3) Neonato de madre HIV positiva y 4) Paciente bajo tratamiento con drogas antivirales. Hoy día se dispone de esquemas terapéuticos combinados con inhibidores de transcriptasa reversa (ITR) e inhibidores de Proteasa (IP) que ha logrado aumentar la supervivencia y mejorar el pronóstico de los pacientes. En este documento se presentan los datos disponibles sobre la confiabilidad y aplicabilidad de las pruebas diagnósticas incluyendo el problema de los costos, el cual sin duda cobra una gran importancia cuando se contempla no sólo desde el punto de vista individual sino que se escala al problema epidemiológico, resultando en todo un reto económico significativo para los países en desarrollo

[Pathogenesis of human immunodeficiency virus infection]. / Patogénesis de la infección por el virus de la inmunodeficiencia humana.

The immunopathogenic mechanisms of the human immunodeficiency virus infection and the precise events that are involved in the clinical latency period are extremely complex and remain unknown. Thus, at the present time, there is no way to prevent or revert the disease, though several and innovative forms of treatment have been developed and different clinical trials on immunization have been conducted. In this review, we describe the molecular biology of HIV-1, the dynamic interactions between HIV and the host, particularly in the clinical latency period, and the factors that induce viral expression. The consequences of HIV infection are influenced by the immunological state of the host, especially by the subtype 1 of CD4+ T cells. The subsequent reaction of the host immune system, with neutralizing antibodies and strong CD8+ T cells response, contain temporarily the course of HIV infection. However, the HIV generates strategies in order to face, evade, and destroy direct or indirectly the immune system. The virus is then activated and replicates without control, producing the progression to AIDS, and inevitably leading to the death. Only the understanding of the pathogenic mechanisms could offer definitive alternative treatment or control of HIV infection.

Effect of a human immunodeficiency virus protease inhibitor on human monocyte function.

Human immunodeficiency virus (HIV) is the cause of acquired immunodeficiency syndrome (AIDS). Encoded by the HIV genome are several precursor proteins that undergo proteolytic cleavage to yield functional proteins. The env precursor protein is cleaved by a cellular protease. The gag precursor protein of HIV (p55), however, is cleaved by a virally encoded aspartate protease (HIV Protease). Cleavage of p55 is required for viral maturation and infectivity. There are also several host cell aspartate proteases that serve important homeostatic functions. Cathepsins D and E are lysosomal aspartate proteases which are believed to play an important role in macrophage function, and it has been suggested that inhibition of these enzymes by an HIV protease inhibitor may exacerbate immunosuppression in AIDS patients. We have studied the effect of SK&F 107461 (a hydroxyethylene dipeptide isostere inhibitor of HIV protease), on various host defense functions of human monocytes. Pepstatin A (an inhibitor of most aspartate proteases) and leupeptin (an inhibitor of serine and cysteine proteases) were included as controls. Although less potent than the prototypic aspartate protease inhibitor pepstatin, SK&F 107461 inhibited partially purified cathepsin D in vitro. However, in cell-based assays, SK&F 107461 had no effect on the degradation of hemoglobin, antigen processing of the protein antigen streptokinase, or secretion of 17-kD IL-1 beta by monocytes at concentrations which inhibit maturation of intracellular virus in HIV infected monocytes. Furthermore, SK&F 107461 had no effect on constitutive candidacidal activity. In contrast, leupeptin and pepstatin A partially inhibited accessory cell function of monocytes in the proliferative response to the recall antigen streptokinase. In addition, leupeptin partially inhibited degradation of hemoglobin.(ABSTRACT TRUNCATED AT 250 WORDS)

Características ultraestructural del reconocimiento específico de un anticuerpo monoclonal anti P24 del VIH-1 en células H9 y E. coli / Ultrastructural characterization of especific recognition of an Mab agains HIV-1 P24 in H9 and E. coli cells

Se realiza la caracterización del reconocimiento específico de un anticuerpo monoclonal contra la proteina P24 del VIH-1 mediante la combinación de métodos inmunológicos y ultraestructurales a través de la inmunomicroscopia electrónica de transmisión con el uso de oro coloidal como marcador en secciones ultrafinas de linfocitos de la linea celular H9 y células de E. coli transformadas para la expresión de las proteinas P24, GP41, GP160 y GP36. Se utilizó para el marcaje post-inclusión una sonda de IgH de cabra antiratón-oro (8 mn). Los resultados demostraron la especificidad del anticuerpo monoclonal utilizado para la proteina P24 en ambos tipos de células, así como la posibilidad de utilizar estos tipos de células, así como la posibilidad de utilizar estos sustratos antigénicos con vistas a la evaluación de otros anticuerpos monoclonales y policlonales relacionados al VIH

[The morphological aspects of the placenta, embryonic tissues and semen in human immunodeficiency virus infections]. / Aspectos morfológicos de placenta, tejidos embrionarios y semen en infecciones por virus de inmunodeficiencia humana.

Tissue samples from a therapeutic curettage performed in a woman with acquired immunodeficiency syndrome and a semen sample of the husband were studied with the electron microscope. The samples were processed according to routine technique for electron microscopy. Calcifications, basement membrane thickening and hyperplasia of Hofbauer cells were seen in the placenta villi. Electron-dense particles of unknown nature, probably of viral origin, were found on the fetal red blood cell membranes, virus-like particles were identified in the endothelial cell nucleus of the brain and lung. Retrovirus-like particles were found in the protein of the seminal plasma. These results suggest that the retrovirus pass through the placenta during early pregnancy.