A Sensitive Quantification of HHV-6B by Real-time PCR

Human herpesvirus (HHV)-6B is a pathogen causing latent infection in virtually all humans. Nevertheless, the interaction of HHV-6B with its host cells is poorly understood. Although HHV-6B is approximately 90% homologous to HHV-6A, it expresses certain B-specific genes. In order to quantify the amount of expressed viral mRNA we have developed a method using real-time PCR on a LightCycler instrument. Here we describe an assay for the detection of the HHV-6B B6 mRNA, but our approach can easily be extended to involve other mRNAs. This method is useful during the study of HHV-6B biology and offers reliable and reproducible, quantitative detection of viral mRNA below the attomol range

Decreased CD8+ T cell response to Epstein-Barr virus infected B cells in multiple sclerosis is not due to decreased HLA class I expression on B cells or monocytes

Background: Patients with multiple sclerosis (MS) have a decreased frequency of CD8(+) T cells reactive to their own Epstein-Barr virus (EBV) infected B cells. We have proposed that this might predispose to the development of MS by allowing EBV-infected autoreactive B cells to accumulate in the central nervous system. The decreased CD8(+) T cell response to EBV results from a general CD8(+) T cell deficiency and also a decreased proportion of EBV-specific T cells within the total CD8(+) T cell population. Because decreased HLA class I expression on monocytes and B cells has been reported in MS and could influence the generation and effector function of EBV-specific CD8(+) T cells, the present study was undertaken to measure the expression of HLA molecules on B cells and monocytes in patients with MS

No increased sperm DNA fragmentation index in semen containing human papillomavirus or herpesvirus

It remains unknown whether human papillomaviruses (HPVs) or human herpesviruses (HHVs) in semen affect sperm DNA integrity. We investigated whether the presence of these viruses in semen was associated with an elevated sperm DNA fragmentation index. Semen from 76 sperm donors was examined by a PCR-based hybridization array that identifies all HHVs and 35 of the most common HPVs. Sperm DNA integrity was determined by the sperm chromatin structure assay. HPVs or HHVs, or both, were found in 57% of semen samples; however, sperm DNA fragmentation index was not increased in semen containing these viruses

Establishment of HTLV-I-infected cell lines from peripheral blood mononuclear cells of Brazilian patients Estabelecimento de linhagens celulares infectadas por HTLV-I a partir de células mononucleares periféricas de pacientes brasileiros

To investigate epidemiological and pathogenetic features of HTLV-I infection, a cohort of carriers has been followed at the USP Teaching Hospital since 1991. This study describes the establishment of cell lines from peripheral blood mononuclear cells (PBMC) of infected subjects. Ex vivo PBMC were cultured with those from a seronegative donor and morphologic evidence of cell transformation was obtained after 90 days with detection of multinucleated cells exhibiting cerebriform nuclei. Integration of HTLV-I proviral DNA and expression of viral antigens was demonstrated in culture by PCR and immunofluorescence. Cell lines were maintained for 240 days, gradually weaned from exogenous IL-2. Immunophenotyping of cell lines on flow cytometry yielded evidence of cell activation. Establishment of HTLV-I-infected cell lines from ex vivo PBMC is feasible and may be useful for studies on lymphocyte phenotypic changes and on mechanisms of HTLV-induced cell proliferation. Moreover they may be used with diagnostic purposes in immunofluorescence tests.<br>Para investigar a epidemiologia e patogênese da infecção por HTLV-I seguimos coorte de portadores dessa retrovirose no HC-FMUSP desde 1991. Este estudo descreve o estabelecimento de linhagens celulares a partir de células mononucleares periféricas (CMP) de indivíduos infectados. As CMP foram cultivadas com as de doador soronegativo, verificando-se após 90 dias evidência morfológica de transformação celular com detecção de células multinucleadas com núcleos cerebriformes. Demonstrou-se integração do DNA proviral e expressão in vitro de antígenos virais pela PCR e imunofluorescência. As linhagens celulares transformadas foram mantidas por 240 dias, com retirada gradual de IL-2 exógena. A imunofenotipagem por citometria de fluxo revelou ativação celular. O estabelecimento de linhagens celulares infectadas por HTLV-I a partir de CMP ex-vivo é exeqüível e pode ser útil na investigação de alterações fenotípicas linfocitárias e dos mecanismos de proliferação celular induzida por esse retrovírus. Podem ainda ser utilizadas com intuito diagnóstico em reações de imunofluorescência