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R Voltz

Publications and source records attributed to R Voltz.

62 records · Page 4Linked to original sources
PubMed1992

Cells of cerebrospinal fluid of multiple sclerosis patients secrete antibodies to myelin basic protein in vitro.

To characterize the role of B lymphocytes in the pathogenesis of Multiple Sclerosis (MS), we have isolated mononuclear cells from cerebrospinal fluid (CSF) and stimulated them with a polyclonal B-cell mitogen (pokeweed mitogen). This study has been done with MS patients selected for the occurrence of an acute attack in the course of the disease and with patients hospitalized for other neurological diseases. Five of the 11 MS patients had B lymphocytes producing in vitro antibodies (Abs) directed against purified human myelin basic protein (hMBP), as revealed by Western blot analysis. None of the 20 patients with other neurological diseases showed such a reactivity. The produced Abs recognized only 1 or 2 hMBP peptides without dominance for a certain peptide. This result emphasizes the presence of B cells producing Abs against MBP in CSF of MS patients and shows the interest of studying mononuclear cells of CSF as a good marker of the pathogenesis.

Acute Disease↗
PubMed1991

Expression of class I major histocompatibility complex antigens in Epstein-Barr virus-carrying lymphoblastoid cell lines and Burkitt lymphoma cells.

Epstein-Barr virus (EBV) carrying lymphoblastoid cell lines (LCLs) and EBV-positive Burkitt lymphoma (BL) cells were compared for their expression of class I antigens of the major histocompatibility complex. Five common BL lines, LCLs, pokeweed mitogen-stimulated blasts and resting B-cells from healthy donors, and eight pairs of BL cells and LCLs, each pair originating from one patient, were tested. Quantitative analysis was performed using a radioimmunoassay; qualitative aspects were studied by one- and two-dimensional gel electrophoresis. In general, LCLs expressed significantly higher amounts of class I antigens than BL cells, the latter showing class I densities similar to or lower than peripheral resting B-cells. From analysis of the expression of class I-specific RNA, there is some evidence that class I antigen expression is regulated on the transcriptional level. In two BL cells studied, class I expression could be enhanced by gamma-interferon, whereas the corresponding LCLs seemed to be refractory to this treatment. One- and two-dimensional gel electrophoresis showed that in some BL lines, in addition to the generally lower class I expression, distinct class I specificities were down-regulated. None of these alterations in class I expression was EBV specific; however, they may well play a role in the recognition of BL cells and LCLs by cellular immune mechanisms. Thus, down-regulation of class I antigens may contribute to the resistance of BL cells to cytotoxic T-lymphocytes, whereas their enhanced expression may improve the recognition of EBV-infected LCLs.

Blotting, Northern↗
PubMed1991

Myasthenia gravis: measurement of anti-AChR autoantibodies using cell line TE671.

Anti-acetylcholine receptor (AChR) antibodies in myasthenia gravis (MG) can be quantitated using AChR extracted from the human rhabdomyosarcoma cell line TE671 (AChRTE671) as a practical alternative to AChR from human amputated limbs (AChRAMP). We compared the two antigen preparations using serum samples from different clinical groups of MG patients (n = 112) and various controls (n = 189). With two exceptions, both tests were positive or negative in the same patients. However, in the generalized MG group, the TE671 assay yielded significantly lower titers than the AChRAMP assay.

Adolescent↗
PubMed1989

Modification of HLA expression as a possible factor in the pathogenesis of Burkitt's lymphoma.

Our data show that: Most BL cells express significantly less HLA class I and II than the corresponding LCLs. Lymphoblastoid cell lines have a much higher HLA class I and II density than normal peripheral blood B cells. There are qualitative differences in class I and II expression in most BL/LCL pairs. These qualitative differences are not caused by EBV infection. They might be due to a selective downregulation of HLA specifities by c-myc activation. We conclude that these modifications of HLA expression may well play a role in the reduced specific immune recognition of Burkitt's lymphoma cells.

Burkitt Lymphoma↗