Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:2.7.7.49 (reverse transcriptase)
 31,746 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The primary structures of 16S rRNAs of Bartonella bacilliformis, an isolate of the cat scratch disease (CSD) bacillus, and a strain phenotypically similar to the CSD bacillus were determined by reverse transcriptase sequencing. These microorganisms were found to be members of the alpha-2 subgroup of the class Proteobacteria. The sequence from B. bacilliformis was most closely related to the rRNA of Rochalimaea quintana (91.7% homology), the etiologic agent of trench fever. The sequence from the isolate of the CSD bacillus showed the greatest homology with Brucella abortus (89.7%) and, when compared with oligonucleotide catalog data, formed a cluster with Rhodopseudomonas palustris, Pseudomonas carboxidovorans, Nitrobacter species, and Bradyrhizobium species. The 16S rRNA sequence was also determined for the Cleveland Clinic isolate, which was previously shown to be phenotypically similar to and approximately 30% related, by DNA hybridization, to the CSD bacillus. The Cleveland Clinic isolate was isolated from a patient not diagnosed with CSD. The rRNAs from these bacteria exhibited 98.2% homology, confirming that this isolate is a second species in the same genus as the CSD bacillus. Our data suggest that neither B. bacilliformis nor the CSD bacillus is the etiologic agent of bacillary epithelioid angiomatosis.
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PMID:16S rRNA sequences of Bartonella bacilliformis and cat scratch disease bacillus reveal phylogenetic relationships with the alpha-2 subgroup of the class Proteobacteria. 171 21

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.
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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

The antiviral activity of recombinant feline interferon-gamma (rFeIFN-gamma) against feline immunodeficiency virus (FIV) was investigated. A persistently FIV(Bang)-infected feline T cell line (FeT-J/Bang) was treated with either rFeIFN-omega, rFeIFN-gamma, or recombinant human IFN-alpha2 (rHuIFN-alpha2), and the culture fluids were tested for antiviral activity by reverse transcriptase (RT) assay. FeT-J/Bang cell cultures treated with rFeIFN-omega showed dose-dependent inhibition of RT activity. In contrast, rFeIFN-gamma treatment had no antiviral effect on FIV replication but instead caused a statistically significant enhancement on day 9 of culture. Antiviral activity of rFeIFN-gamma was also tested on feline peripheral blood mononuclear cells (PBMC). PBMC cultures were inoculated with FIV(Bang) and simultaneously treated with either rFeIFN-omega, rFeIFN-gamma, or rHuIFN-alpha2. FeIFN-gamma had no effect on FIV replication, unlike the rFeIFN-omega and rHuIFN-alpha2, which had strong anti-FIV effects. In another study, rFeIFN-gamma treatment was initiated 3 days before FIV(Bang) infection, the day of FIV(Bang) infection, or 3 days post-FIV(Bang) infection and then tested for antiviral activity. The time of initiating rFeIFN-gamma treatment had no effect on the antiviral activity. Hence, these results suggest that unlike rHuIFN-alpha2 and rFeIFN-omega, rFeIFN-gamma has no inhibitory effect on FIV replication in PBMC but causes a slight enhancement in a feline T cell line.
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PMID:Feline immunodeficiency virus lacks sensitivity to the antiviral activity of feline IFN-gamma. 1179 61

Turkey poults which were surgically or chemically bursectomised after hatching, and inoculated with the lymphoproliferative disease (LPD) virus at 3(1/2) weeks of age, developed typical tumourous lesions in various organs (pancreas, spleen, thymus, liver, gonads and kidneys) to the same extent as intact but inoculated controls. Plasma virus-associated reverse transcriptase activity (as an estimation of viraemia) developed at a higher rate in poults neonatally treated with 16 mg of cyclophosphamide. The chemically bursectomised birds were found to have markedly reduced serum gamma-globulins levels, and low levels or absence of agglutinins to sheep red blood cells and to killed Brucella abortus following immunisation with these antigens. Inoculation of turkey poults with LPD virus did not cause inhibition of the humoral immune response in intact birds but reduced significantly antibody production in surgically bursectomised poults. Since infection with LPD virus was previously shown to cause hypergammaglobulinaemia, and more specifically, a marked increase in serum IgG (7S) levels, it was suggested that the LPD tumour cells might be antibody-producing B-lymphoid cells. However, results presented here indicate that LPD lesions and viraemia can develop even in turkeys lacking any appreciable B-cell activity.
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PMID:Lymphoproliferative disease of turkeys: effect of chemical and surgical bursectomy on viraemia, pathogenesis and on the humoral immune response. 1876 44

A reverse transcriptase real-time polymerase chain reaction was developed to estimate the expression of the gamma-interferon (IFN-gamma) and interleukin-4 (IL-4) in cattle vaccinated with Brucella abortus RB51. Peripheral blood mononuclear cells of heifers vaccinated with B. abortus RB51 were stimulated in vitro with the same antigen and with Concanavalin A. The data obtained (presence of IFN-gamma expression and absence of IL-4 expression) confirmed the cell-mediated immune response to strain RB51 antigen. Furthermore, the expression of these two cytokines was quantified and the results showed values of IFN-gamma expression to be significantly higher in vaccinated than non-vaccinated animals.
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PMID:Study of the gene expression of Th1 and Th2 cytokines in the immune response of cows vaccinated with Brucella abortus RB51. 2042 57