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L W Whitney

Publications and source records attributed to L W Whitney.

At least 19 recordsLinked to original sources

Radioactive 33-P probes in hybridization to glass cDNA microarrays using neural tissues.

cDNA microarrays are becoming widespread tools in the study of complex gene expression patterns with applications using cells lines, animal model systems, and human disease. Glass cDNA microarrays using fluorescent labeled cDNA probes require a large amount of input RNA usually not available in many neuroscience applications. Here we demonstrate a technique for the use of 33-P labeled cDNA probes in hybridizations to the same glass cDNA arrays used for fluorescent applications. This approach allows the use of low quantities of RNA, common phosphoimaging scanners, data acquisition software, and standard DNA and RNA labeling protocols, while being consistent and interchangeable with glass-based cDNA array technology.

DNA Probes↗

Analysis of gene expression in mutiple sclerosis lesions using cDNA microarrays.

In multiple sclerosis (MS) patients, a coordinated attack of the immune system against the primary constituents of oligodendrocytes and/or the myelin sheath of oligodendrocytes results in the formation of lesions in the brain and spinal cord. Thus far, however, a limited number of genes that potentially contribute to lesion pathology have been identified. Using cDNA microarray technology, we have performed experiments on MS tissue monitoring the expression pattern of over 5,000 genes and compared the gene expression profile of normal white matter with that found in acute lesions from the brain of a single MS patient. Sixty-two differentially expressed genes were identified, including the Duffy chemokine receptor, interferon regulatory factor-2, and tumor necrosis factor alpha receptor-2 among others. Thus, cDNA microarray technology represents a powerful new tool for the identification of genes not previously associated with the MS disease process.

Brain↗

A mechanism for selective induction of 2'-5' oligoadenylate synthetase, anti-viral state, but not MHC class I genes by interferon-beta in neurons.

Interferon-inducible expression of major histocompatibility class I genes has previously been found to be quantitatively and functionally deficient in neurons compared to other somatic cells or other neural cell types including astrocytes. This deficiency is a key component of neuronal immunoprivilege during viral infections of the CNS. To the contrary, in the present study, induction of functional antiviral state by IFN-beta in neurons compared to astrocytes was found to be highly efficient with respect to both viral replication and protection from cytopathic effects. A candidate antiviral state gene found to be efficiently induced in neurons by IFN-beta was the 2'-5'-oligoadenylate synthetase (OAS) gene. Unlike MHC class I genes, induction of OAS was comparable in neurons and astrocytes indicating differential expression in these neural cell types. Analysis of OAS gene promoter activity indicated that induction of the OAS gene by IFN-beta was dependent on a region containing the interferon stimulated responsive element (ISRE). In contrast, a construct containing the MHC class I-ISRE responsible for induction by IFN-beta in astrocytes was not responsive to IFN-beta in neurons. Therefore, transcription factor binding to the OAS- and MHC-ISREs was analyzed. While the OAS and MHC Class I site bound equal amounts of the transcriptional repressor IRF-2, the OAS-ISRE preferentially interacted with the transcriptional activator ISGF3 in response to IFN-beta. Further, unlike neurons, upregulation of MHC class I genes in astrocytes was related to binding of IRF-1 instead of IRF-2 to the MHC-ISRE. It is proposed that selective activation of anti-viral state genes compared to MHC class I genes by IFN-beta in neurons is mediated by preferential induction and binding of ISGF3 to anti-viral state gene ISREs but not the MHC-ISRE.

2',5'-Oligoadenylate Synthetase↗