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1.  Recombinant NFAT1 (NFATp) is regulated by calcineurin in T cells and mediates transcription of several cytokine genes. 
Molecular and Cellular Biology  1996;16(7):3955-3966.
Transcription factors of the NFAT family play a key role in the transcription of cytokine genes and other genes during the immune response. We have identified two new isoforms of the transcription factor NFAT1 (previously termed NFATp) that are the predominant isoforms expressed in murine and human T cells. When expressed in Jurkat T cells, recombinant NFAT1 is regulated, as expected, by the calmodulin-dependent phosphatase calcineurin, and its function is inhibited by the immunosuppressive agent cyclosporin A (CsA). Transactivation by recombinant NFAT1 in Jurkat T cells requires dual stimulation with ionomycin and phorbol 12-myristate 13-acetate; this activity is potentiated by coexpression of constitutively active calcineurin and is inhibited by CsA. Immunocytochemical analysis indicates that recombinant NFAT1 localizes in the cytoplasm of transiently transfected T cells and translocates into the nucleus in a CsA-sensitive manner following ionomycin stimulation. When expressed in COS cells, however, NFAT1 is capable of transactivation, but it is not regulated correctly: its subcellular localization and transcriptional function are not affected by stimulation of the COS cells with ionomycin and phorbol 12-myristate 13-acetate. Recombinant NFAT1 can mediate transcription of the interleukin-2, interleukin-4, tumor necrosis factor alpha, and granulocyte-macrophage colony-stimulating factor promoters in T cells, suggesting that NFAT1 contributes to the CsA-sensitive transcription of these genes during the immune response.
PMCID: PMC231392  PMID: 8668213
3.  Normal peripheral T-cell function in c-Fos-deficient mice. 
Molecular and Cellular Biology  1994;14(3):1566-1574.
The ubiquitous transcription factors Fos and Jun are rapidly induced in T cells stimulated through the T-cell antigen receptor and regulate transcription of cytokines, including interleukin 2, in activated T cells. Since positive and negative selection of thymocytes during T-cell development also depends on activation through the T-cell receptor, Fos and Jun may play a role in thymocyte development as well. Fos and Jun act at several regulatory elements in the interleukin 2 promoter, including the AP-1 and NFAT sites. Using antisera specific to individual Fos and Jun family members, we show that c-Fos as well as other Fos family members are present in the inducible AP-1 and NFAT complexes of activated murine T cells. Nevertheless, c-Fos is not absolutely required for the development or function of peripheral T cells, as shown by using mice in which both copies of the c-fos gene were disrupted by targeted mutagenesis. c-Fos-deficient mice were comparable to wild-type mice in their patterns of thymocyte development and in the ability of their peripheral T cells to proliferate and produce several cytokines in response to T-cell receptor stimulation. Our results suggest that other Fos family members may be capable of substituting functionally for c-Fos during T-cell development and cytokine gene transcription in activated T cells.
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PMCID: PMC358515  PMID: 8114694
5.  Mortality in the elderly during respite hospital care. 
The Ulster Medical Journal  1989;58(2):131-133.
This study examined the mortality in the elderly during 243 respite hospital admissions. Sixty-four dependent elderly patients entered a regular respite care scheme and were admitted to hospital for a period of 4 weeks out of every 12 weeks. The mortality rate in hospital was one death per 976 days, in comparison to one death per 1296 days at home. This small increase in mortality should not deprive patients and their carers from access to respite care.
PMCID: PMC2448219  PMID: 2603260
7.  Effect of excess water on the desilylation of oligoribonucleotides using tetrabutylammonium fluoride. 
Nucleic Acids Research  1993;21(20):4739-4741.
The most commonly available 2' hydroxyl protecting group used in the synthesis of oligoribonucleotides is the tert-butyldimethylsilyl moiety. This protecting group is generally cleaved with 1 M tetrabutylammonium fluoride (TBAF) in tetrahydrofuran (THF). The efficiency of this reaction was tested on ribonucleotidyldeoxythymidine dinucleotides (AT, CT, GT, and UT). We have found that the efficiency of desilylation of uridine and cytidine is greatly dependent on the water content of the TBAF reagent. Conversely, the water content of the TBAF reagent [up to 17% (w/w)] had no detectable effect on the rate of desilylation of adenosine and guanosine. It was concluded that for effective desilylation of pyrimidine nucleosides the water content of the TBAF reagent must be 5% or less, which is readily achieved using molecular sieves. TBAF dried in such a manner was shown to be effective in deprotecting an oligoribonucleotide containing both purine and pyrimidine residues.
PMCID: PMC331499  PMID: 8233822
8.  Cyclosporin A sensitivity of the NF-kappa B site of the IL2R alpha promoter in untransformed murine T cells. 
Nucleic Acids Research  1994;22(11):2134-2142.
We have investigated the characteristics of IL2R alpha gene induction in untransformed murine T cells. Induction of IL2R alpha mRNA by TCR/CD3 ligands in a murine T cell clone and in short-term splenic T cell cultures was inhibited by protein synthesis inhibitors and by CsA. This result was contrary to previous observations in JURKAT T leukemia cells and human peripheral blood T cells, suggesting a difference in the mechanisms of IL2R alpha gene induction in these different cell types. The CsA sensitivity of IL2R alpha mRNA induction represented a direct effect on the TCR/CD3 response, and was not due to CsA-sensitive release of the lymphokines IL2 or tumour necrosis factor alpha (TNF alpha) and consequent lymphokine-mediated induction of IL2R alpha mRNA. The NF-kappa B site of the IL2R alpha promoter was essential for gene induction through the TCR/CD3 complex, and the induction of reporter plasmids containing multimers of this site was significantly inhibited by CsA. Northern blotting analysis indicated that while the p65 subunit of NF-kappa B was constitutively expressed and not appreciably induced upon T cell activation, mRNA for the p105 precursor of p50 NF-kappa B was induced in response to TCR/CD3 stimulation and this induction was sensitive to CsA. Electrophoretic mobility shift assays and antiserum against the p50 subunit of NF-kappa B indicated that p50 was a component of the inducible nuclear complex that bound to the IL2R alpha kappa B site. Appearance of the kB-binding proteins was insensitive to CsA at early times after activation (approximately 15 min), but was partially sensitive to CsA at later times. Based on these results, we propose that the NF-kappa B site of the IL2R alpha promoter mediates at least part of the CsA sensitivity of IL2R alpha gene induction in untransformed T cells, possibly because de novo synthesis of p105 NF-kappa B is required for sustained IL2R alpha expression.
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PMCID: PMC308132  PMID: 8029023

Results 1-11 (11)