Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound   Target Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound

---

Query: EC:2.7.7.49 (reverse transcriptase)
31,746 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Cytokines are now considered as constitutive factors of the brain. Some of them are involved in the mechanism regulating lineage commitment and cellular differentiation of the central nervous system (CNS). We describe here the analysis of gene expression in cortex and hippocampus, of interleukin-1 alpha (IL1), interleukin-2 (IL2), interleukin-6 (IL6), macrophage-colony stimulating factor-1 (MCSF) and monocyte chemoattractant protein-1 (MCP1) in fetal (day 18 of gestation; G18), newborn (postnatal day 2; P2), young (postnatal day 21; P21) and adult rat using the reverse transcriptase-polymerase chain reaction (RT-PCR). IL6 and MCP1 mRNA presented distinct patterns of expression levels: IL6 mRNA level is most highly expressed in the embryonic cortex, whereas MCP1 is expressed at a maximal level in the postnatal day 2 cortical area. In the hippocampus, IL6 is most expressed at the adult stage and MCP1 exhibits an equal level of expression from day two to the adult stage. However, under our experimental conditions, IL1 alpha, IL2 and MCSF mRNA were not observed. Thus, certain cytokine genes, each with a specific pattern, are expressed in the rat CNS in adult and during ontogenesis. These observations suggest that cytokines might be involved as regulating factors promoting CNS development.
...
PMID:Developmental expression of cytokine genes in the cortex and hippocampus of the rat central nervous system. 780 81

Immunity to Brucella abortus crucially depends on antigen (Ag)-specific T-cell mediated activation of macrophages, which are the major effectors of cell-mediated killing of this organism. Ribosomal preparations have been used as vaccines against several pathogens, including B. abortus, conferring a high degree of protection. In the present study, we have examined the pattern of T-helper (Th) cell response from infected BALB/c mice after in vitro stimulation with recombinant (r) L7/L12 ribosomal protein or gamma-irradiated B. abortus. In addition to Ag-specific proliferation, CD4+ T cells were tested for interleukin-2 (IL-2), IL-4 and interferon-gamma (IFN-gamma) mRNA expression and secretion. Detection of cytokine transcripts and secreted cytokines was performed using reverse transcriptase (RT)-polymerase chain reaction (PCR) and specific ELISA assays. Primed CD4+ T cells proliferated to the recombinant protein or whole B. abortus. The functional cytokine profile of the proliferating cells was typical of a Th1 cell phenotype, as we detected transcripts for IL-2 and IFN-gamma but not IL-4. Among the cytokines analysed, only IFN-gamma produced in the Th cell culture supernatants was detected by ELISA when bacteria or recombinant protein were used. Thus, rL7/L12 ribosomal protein and gamma-irradiated B. abortus preferentially stimulated IFN-gamma-producing Th1 cells after in vitro stimulation. The results of this study provide for the first time an explanation of why ribosomal vaccines may protect against intracellular infections, and an experimental basis for identifying polypeptides from a pathogen which stimulates the desired cytokine profile and Th cell response crucial for the design of genetically engineered candidate vaccines.
...
PMID:Recombinant L7/L12 ribosomal protein and gamma-irradiated Brucella abortus induce a T-helper 1 subset response from murine CD4+ T cells. 787 46

Cytotoxic T cells have been implicated in the control of the progression of human melanoma. Most studies on human tumor T cell immunity have focused on the CD3+CD8+ cytotoxic T lymphocyte (CTL) phenotype; however, CD3+CD4+ CTL are important effector cells in other diseases and may also contribute to antimelanoma immunity. In this study we compared the functional activity of CD3+CD4+ and CD3+CD8+ CTL lines generated against autologous melanoma cells. CD8+ CTL had twofold higher cytotoxicity and serine esterase activity than CD4+ CTL. CD8+ CTL also were better binders to autologous melanoma cells. Binding of both CD4+ and CD8+ CTL to melanoma cells was significantly inhibited by ICAM-1 mAb. Interleukin-2 (IL-2) and IL-4 secretion was induced in both CD4+ and CD8+ CTL after stimulation by melanoma cells. A reverse transcriptase polymerase chain reaction performed on specific messenger RNA showed that both CD4+ and CD8+ CTL expressed IL-1, IL-2 and IL-4; CD4+ CTL also expressed interferon gamma (IFN). Both CTL phenotypes expressed receptors for IL-2 and IFN but only CD4+ CTL expressed the receptor for IL-4. Methods to augment CD4+ CTL growth were assessed using different combinations of cytokines. The combination of IL-2, IL-4 and IFN provided the optimal stimulation. Treatment of melanoma target cells with IL-4 and IFN enhanced CD4+ CTL recognition activity. CD4+ T cells are associated with antigen memory response and helper function, therefore activation of CD4+ CTL may be more beneficial with respect to long-term protective antimelanoma immunity.
...
PMID:Characterization and augmentation of CD4+ cytotoxic T cell lines against melanoma. 792 47

Rejection continues to be a major cause of graft loss in small intestine transplantation (SIT). We have studied, by semiquantitative reverse transcriptase PCR (rtPCR), the intragraft expression of cytokines relevant to rejection in a rat model. Heterotopic SIT grafts were performed from Lewis x Brown Norway F1 donors into Lewis recipients. The isograft control was Lewis into Lewis. Five animals in each isograft and allograft group were sacrificed on POD 3, 5, 7, 8, 9, 10, 12, and 14. mRNA was isolated from portions of the terminal ileum and rtPCR performed to amplify message for interleukin-2 (IL-2), IL-2 receptor (IL-2R), interleukin-6 (IL-6), tumor necrosis factor alpha (TNF-alpha), and interferon gamma (IFN-gamma). Semiquantitative analysis was performed using 32P radionuclide incorporation and scintillation counting. The results were expressed as percent activity compared with beta-actin. Histologic correlation with cytokine expression was made. On POD 3 after SIT there was no evidence of rejection by histology and all cytokines studied showed no difference between the isograft and the allograft. On POD 5 the first evidence of mild rejection was seen on histology and IL-6, IFN-gamma, TNF-alpha showed a significant up regulation in the allograft that persisted through POD 14. mRNA for IL-2 was not significantly upregulated until POD 7 and persisted until POD 14. IL-2R was constitutively expressed in both isograft and allograft and was not a reliable predictor of rejection. Histologic rejection was moderately severe by POD 7 and severe between POD 8 and 14 correlating with the increasing expression of IL-6, IFN-gamma, and TNF-alpha. In summary, we have shown that increasing expression of mRNA for IL-6, IFN-gamma, and TNF-alpha not only correlated with severity of rejection but that upregulation began early when histologic evidence of rejection first occurred.
...
PMID:The correlation of intragraft cytokine expression with rejection in rat small intestine transplantation. 794 Jun 88

We and others have described methods to label specific nucleic acid sequences in fixed cells by reverse in situ transcription (IST). They are simple alternatives to the tedious steps of in situ hybridization with labeled probes. We have favored use of thermostable DNA polymerases after heat denaturation of template secondary structure, accompanied by synthesis of cDNA from an annealed primer, but the approach has been limited by the low reverse transcriptase (RT) activity of Taq polymerase and delayed detection methods. We have improved the technique by the use of recombinant Thermus thermophilus (rTth) DNA polymerase and fluorescein-12-dUTP (FIST). Jurkat T lymphocytes were stimulated with ionomycin + phorbol myristate acetate to produce interleukin-2 (IL-2) mRNA in vitro overnight. They were cytospun onto slides and fixed in 70% ethanol + 30% DEPC-treated water, acetone, and air-dried. The slides were placed on a temperature-controlled heating block, and the cell spot was covered with a plastic coverslip. The temperature was raised to 95 degrees C, and 5-10 microliters of modified Perkin-Elmer/Cetus rTth RT reaction mix was injected under the edge of the coverslip. Each 10 microliters of mix in DEPC-water contained 10 mM Tris-HCl, pH 8.3, 90 mM KCl, 1 mM MnCl2, 1 mM dithiothreitol, 10 U placental ribonuclease inhibitor, 0.125 mM dA,C,GTPs, 0.1 mM fluorescein-12-dUTP, 2 U rTth DNA polymerase, and 4 pM 22-mer oligonucleotide primer, which spanned the second intron of IL-2. After 3 min at 95 degrees C, 1 min at 50 degrees C and 10 min at 72 degrees C, the slides were washed in 0.5 x phosphate-buffered saline, pH 7.0, at 42 degrees C, in 70% ethanol, 100% ethanol, and air-dried. The cells were mounted in antifade solution (2% n-propyl gallate in 70% glycerol), and could be viewed immediately by fluorescence microscopy. Image analysis showed that stimulated Jurkat cells were brighter than uninduced controls or those treated with RNase or without polymerase or primer. FIST appears to be useful for the detection of specific mRNAs in single cells.
...
PMID:In situ transcription with Tth DNA polymerase and fluorescent nucleotides. 798 81

Administration of interleukin-2 (IL-2) leads to pulmonary vascular leak. This form of pulmonary edema has previously been postulated to be due to the in vivo induction of tumor necrosis factor-alpha (TNF-alpha). To determine whether TNF-alpha plays a role in IL-2-induced pulmonary vascular leak, we performed in situ hybridization of lung sections and reverse transcriptase-polymerase chain reaction of bronchoalveolar lavage macrophages from IL-2-challenged mice. The results confirm an in situ upregulation of TNF-alpha mRNA expression in the lungs associated with vascular leak. In addition, a significant increase in TNF-alpha protein production was found in the lung following IL-2 administration, as measured by TNF-alpha-specific ELISA of lung supernatants (P = 0.028). Intravenous administration of a soluble TNF receptor significantly diminished IL-2-induced pulmonary vascular leak (P = 0.006). These findings confirm a central role for TNF-alpha in mediating the pulmonary vascular leak associated with IL-2 toxicity.
...
PMID:Tumor necrosis factor-alpha plays a central role in interleukin-2-induced pulmonary vascular leak and lymphocyte accumulation. 803 44

DAB486IL-2 is a recombinant toxin with the cell surface-binding domain of diphtheria toxin (DT) replaced by interleukin-2 (IL-2). To correlate clinical response with expression of components of the IL-2 receptor (IL-2R), 14 patients with cutaneous T-cell lymphoma (CTCL) received five daily 90-minute infusions every 21 days. There were no complete responses, 1 partial response (PR), 2 major biologic effects (major cutaneous improvement without change in circulating neoplastic cells), 3 stable disease (SD), and 8 progressive disease (PD). Responders had easily detected expression of CD25 (Tac; alpha-chain of IL-2R) in skin, and in two responders expression of the beta chain of the IL-2 receptor (beta-IL-2R) was detectable by reverse transcriptase-polymerase chain reaction. CD25 was also detected in 8 of 11 SD or PD patients, with beta-IL-2R in 3 of 8 SD or PD patients. Two of the three responders had anti-DT antibodies before treatment. Reversible increased hepatic transaminases occurred in 13 of 14 patients during the first course, with decreased frequency in repeated courses. The maximal serum concentration after the first infusion of DAB486IL-2 varied (1,369 +/- 1,155 ng/mL [mean +/- SD]; n = 14; range, 55 to 3,999 ng/mL) with a short half-life (T1/2 beta = 0.21 +/- 0.12 h [mean +/- SD]; range, 0.099 to 0.57 h). The area under the concentration curve varied inversely with anti-DT antibody titer. We conclude that DA-B486IL-2 has valuable activity in certain patients with CTCL. Expression of the IL-2R may be necessary but is not sufficient to predict response.
...
PMID:Chimeric fusion protein toxin DAB486IL-2 in advanced mycosis fungoides and the Sezary syndrome: correlation of activity and interleukin-2 receptor expression in a phase II study. 808 Sep 84

As shown recently, CD3+/TcR+ functional T lymphocytes can be derived in culture from embryonic liver cell precursors at a gestational age (6-8 weeks) preceding the colonization of the epithelial thymus. In this report, we analyzed the V beta repertoire of T lymphocytes derived from embryonic liver by applying a quantitative reverse transcriptase-polymerase chain reaction technique. To this end, oligonucleotide primers for C alpha or the various human V beta have been used to study both freshly derived embryonic liver cell suspensions and CD3+/TcR+ populations derived after approximately 6 weeks upon stimulation with 1% phytohemagglutinin and culture in 100 units/ml recombinant interleukin-2. In order to exclude possible contaminations with mother-derived T lymphocytes, only T cells displaying both X and Y chromosomal sequences (i.e. derived from male embryos) were further analyzed. While neither C alpha nor the various V beta could be detected in fresh liver cells, C alpha and the large majority of V beta were detected in in vitro cultured populations. The levels of the various V beta expressed by embryo-derived T cells was similar to that detected in adult peripheral blood-derived T lymphocytes. These experiments indicate that the immature liver precursors can potentially give rise in vitro to T cells which express a wide V beta repertoire and may provide a suitable in vitro system for the analysis of the selection processes mediated by either major histocompatibility complex antigen or superantigens.
...
PMID:Expression of a wide T cell receptor V beta repertoire in human T lymphocytes derived in vitro from embryonic liver cell precursors. 808 40

The expression of three chemoattractant cytokine (chemokine) messenger (m)RNAs in the murine renal cell carcinoma (RENCA) from mice treated with a combination of interferon-alpha (IFN-alpha) and interleukin-2 was examined and related to tumor infiltration by inflammatory leukocytes. Using a semi-quantitative reverse transcriptase polymerase chain reaction assay, mRNAs encoding the KC, JE, and IP-10 genes were all elevated in tumor tissue from mice treated systemically with IFN-alpha/interleukin-2 for 4 days. Similarly, the mRNA for tumor necrosis factor-alpha (TNF-alpha) was also increased in tumors from treated as compared to control animals. The same tumors showed a significant increase in Mac-1+ leukocytes, which correlated well with the increase in chemokine and TNF-alpha gene expression. The renal cell carcinoma tumor itself may be responsible for the expression of chemokine genes in the tumor bed following cytokine therapy. Cultures of freshly explanted RENCA cells expressed significant levels of chemokine mRNAs when stimulated in vitro with IFN alpha, IFN gamma, and/or interleukin-2, demonstrating that this tumor cell has potential for expression of these genes in vivo. In contrast, TNF-alpha expression was not detected in cultured tumor cells. Thus TNF-alpha may be expressed by infiltrating monocytes following exposure to recombinant cytokine therapy.
...
PMID:Chemokine gene expression in the murine renal cell carcinoma, RENCA, following treatment in vivo with interferon-alpha and interleukin-2. 816 Jul 74

Taking advantage of the reverse transcriptase-polymerase chain reaction (RT-PCR), we have analyzed T cell receptor gamma-chain mRNA of synovial fluid gamma/delta T cells from patients with rheumatoid arthritis (RA) in comparison with those of peripheral blood mononuclear cells (PBMC) from RA patients and healthy individuals. The quantitative RT-PCR method in conjunction with nucleotide sequencing revealed the frequent usage of the V gamma 3 gene segment in RA synovial fluid mononuclear cells (SFMC) (p < 0.01) which in PBMC of healthy individuals occurred rarely. PBMC of most healthy individuals expressed the V gamma 9 gene predominantly (p < 0.01) as expected. However, only half of RA patients showed elevated levels of the V gamma 9 gene expression in their PBMC. The gamma-chain mRNA containing the V gamma 3 gene in RA SFMC showed no conserved junctional sequence (complementarity-determining region 3). To investigate the nature of ligands recognized by the V gamma 3-bearing T cells, we analyzed V gamma gene usage of RA SFMC, RA PBMC, and normal PBMC stimulated with Mycobacterium tuberculosis (MT) or MT plus interleukin-2 since there is mounting evidence of high reactivity of RA SFMC to MT and mycobacterial heat-shock protein 65. However, the V gamma usage appeared to be mostly V gamma 9 in RA SFMC, RA PBMC and normal PBMC. Taken together these results suggest that an as yet unknown antigen(s) (other than MT) might select gamma/delta T cells expressing the V gamma 3 gene in RA SFMC.
...
PMID:The biased V gamma gene usage in the synovial fluid of patients with rheumatoid arthritis. 818 23


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>

---