title: [Changes in cellular transcription on terms of the type of proliferative stimulus in immune-reactive lymphocyte cultures].
abstract: Transcriptase activities were investigated in cell extracts of human circulating lymphocyte cultures stimulated for proliferation with polyclonal mitogens like PHA, PPD, and endotoxin from Salm. typhimurium S, and also with two polynucleotides. Enzymic activity of the cell extracts was tested differentiatelly for direct (DNA/RNA) and reverse (RNA/DNA) transcription, using appropriate template-primers: activated DAN and poly (dA). r(pU)10 for direct transcription, and poly (rA.rC. rU), poly (dA) x d(pT)10, and poly (rA). d(pT)12-18 for reverse transcription. All lymphoproliferative stimulators are able to enhance simultaneously the cellular mitosis and the direct transcriptase activity in the cell. There is a good correlation between the two effects. Enzyme affinity to natural DNA is higher than to synthetic poly (dA) r(pU)10 PHA, a mitogen for T lymphocyte, enhances the eukaryote type of reverse transcriptase, while among the mitogens for B lymphocyte the PPD enhances an intermediate (viral-eukaryotic) type of reverse transcriptase, and ENDO is not stimulatory for reverse transcription. Duplex polyribonucleotides have an adjuvant activity: they intensify the action of stimulators but they have not a direct enhancing activity. The different transcriptases involved in the lymphocyte differentiation and proliferation may be targets for clinically useful immunosuppressive drugs differentiated for T and B cells.
authors.affiliation: Institutul de ftiziologie Bucureşti.
authors.forename: E
authors.initials: E
authors.lastname: Păunescu
authors.forename: M
authors.initials: M
authors.lastname: Dănălache-Dumitrescu
authors.forename: M
authors.initials: M
authors.lastname: Stoinescu
mesh_terms: D004247:DNA / Q000276:immunology; D012321:DNA-Directed RNA Polymerases / Q000276:immunology*; D006801:Humans; D008213:Lymphocyte Activation; D008214:Lymphocytes / Q000276:immunology*; D008934:Mitogens; D011131:Polyribonucleotides / Q000276:immunology; D012313:RNA / Q000276:immunology; D048348:Reverse Transcription / Q000276:immunology; D013698:Templates, Genetic
chemical_list: D008934:Mitogens; D011131:Polyribonucleotides; D012313:RNA; D004247:DNA; D012321:DNA-Directed RNA Polymerases