A simple and rapid method for the quantitation of secreted hepatitis B virions in cell culture models.

Cell culture models for hepatitis B virus (HBV) remain the mainstay for screening and testing the efficacy of anti‑hepatitis B virus agents. Gradient‑based ultracentrifugation followed by Southern Blotting is used for hepatitis B virion estimation in cell culture; this method has several limitations. We report the development of an assay using a commercially available HBsAg‑ELISA plate for immunocapture followed by real‑time PCR for quantification of hepatitis B virions in cell cultures. This assay is rapid, highly sensitive (50 copies/reaction) and highly specific for virion‑associated DNA. In addition, the assay requires only 20 μL of supernatant, allowing scaling down of transfections.

Consideraciones acerca del diagnostico inmunologico del sindrome torch / Considerations about the immunologic diagnosis of TORCH syndrome

Se revisa someramente la epidemiologia del sindrome TORCH en Colombia. Se enumeran los metodos de diagnostico inmunologico disponibles para las diferentes entidades y se describe detenidamente la tecnica de Elisa. Se hace enfasis en la importancia de la deteccion de IgM especifica mediante la tecnica de inmunocaptura, como un marcador de infeccion de fase aguda y se introduce el concepto de la deteccion de IgA especifica, igualmente mediante inmunocaptura, como un marcador de infeccion aguda de mayor sensibilidad y especificidad que la misma IgM.

Abstract The epidemiology of TORCH syndrome In Colombia is briefly reviewed, the methods available for the immunologic diagnosis of the different entitles are listed and the ELISA is described in detail. Emphasis is put on the importance of detecting specific IgM by the IMMUNOCAPTURE technique, as a marker for acute infection; the concept of the detection of a specific IgA (by the same method) as a marker for acute infection but with greater specifically and sensitivity than IgM, Is Introduced