RESUMEN
Legionella pneumophila, serogroup 1, was identified by direct immunofluorescence in the lung and liver graft from a 2 1/2-month-old infant who underwent orthotopic liver transplantation because of fulminant hepatic failure secondary to neonatal hepatitis. The patient died of respiratory failure owing to this infection 22 days after transplantation despite treatment with erythromycin lactobionate. To our knowledge, this represents the first reported case of hepatic infection with Legionella in liver transplant recipients.
Asunto(s)
Legionella pneumophila/aislamiento & purificación , Enfermedad de los Legionarios/microbiología , Trasplante de Hígado , Hígado/microbiología , Técnica del Anticuerpo Fluorescente , Humanos , Lactante , Hígado/patología , Pulmón/microbiología , Masculino , Esputo/microbiologíaRESUMEN
Studies of separated peripheral blood mononuclear cell subsets have indicated that the CD8+ lymphocyte is the primary cell type responsible for suppressing human immunodeficiency virus (HIV) replication by infected CD4+ cells. The effect of this antiviral activity is dose-dependent and does not involve killing of the infected cell. These observations indicate that this response is distinct from the anti-HIV cytotoxic mechanisms also described for human CD8+ cells.
Asunto(s)
Linfocitos T CD4-Positivos/microbiología , Seropositividad para VIH/inmunología , VIH-1/crecimiento & desarrollo , Linfocitos T/inmunología , Antígenos de Diferenciación de Linfocitos T/análisis , Linfocitos T CD4-Positivos/inmunología , Antígenos CD8 , Supervivencia Celular , Células Cultivadas , Humanos , Inmunidad Celular , Técnicas In Vitro , Masculino , Replicación ViralRESUMEN
Optimal conditions for demonstrating the presence of infectious human immunodeficiency virus in peripheral blood mononuclear cells (PMCs) from seropositive individuals involved cocultivation of infected cells with phytohemagglutinin-stimulated PMCs from seronegative donors in the presence of 2 micrograms of Polybrene per ml. The size of the culture vessel also influenced the results; smaller numbers of infected cells were detected under conditions of increased cell density. In addition, an increased normal donor/patient PMC ratio was helpful. The cocultivation approach permitted identification of human immunodeficiency virus in over 90% of seropositive individuals with different clinical conditions. Moreover, reconstruction experiments indicated that this method allows detection of one productively infected CD4+ cell in a population of over 10(6) PMCs.