Inhibition of alloresponse by a human trophoblast non-coding RNA suppressing class II transactivator promoter III and major histocompatibility class II expression in murine B-lymphocytes
| Autor: | Graeme L. Hammond, Alfred L. M. Bothwell, Arnar Geirsson |
|---|---|
| Rok vydání: | 2004 |
| Předmět: |
Pulmonary and Respiratory Medicine
Genes MHC Class II Transfection Major histocompatibility complex Mice Antigen Gene expression CIITA Animals Humans Northern blot Promoter Regions Genetic B-Lymphocytes Transplantation MHC class II biology Nuclear Proteins RNA Promoter Blotting Northern Molecular biology Trophoblasts Trans-Activators biology.protein Surgery Cardiology and Cardiovascular Medicine |
| Zdroj: | The Journal of Heart and Lung Transplantation. 23:1077-1081 |
| ISSN: | 1053-2498 |
| Popis: | Background Trophoblasts are a model of natural allograft tolerance. A unique characteristic is the complete lack of expression of all classic major histocompatibility (MHC) antigens. We cloned a human trophoblast non-coding RNA (TncRNA) that suppresses MHC class II expression through inhibition of the class II transactivator (CIITA) promoter. We assessed the functional affects of TncRNA on an alloresponse and dissected the functional domain on CIITA promoter III. Methods Murine B-cell line A20 was transfected with TncRNA. Class II suppressed clones were selected and characterized by flow cytometry and Northern analysis. The clones were then subjected to lymphocyte proliferation assay to assess the stimulation of T-lymphocytes. CIITA promoter III-luciferase reporter plasmids were used with TncRNA plasmids in co-transfection assays; 5′-end deletion plasmids were used to dissect the promoter. Results Significant suppression of I-A d expression was seen. Northern blot scans demonstrated 84% to 93% suppression of class II transcripts. Lymphocyte proliferation assay demonstrated a 50% and 64% inhibition of lymphocyte stimulation in the 2 clones, compared to A20 wild type. Dissection of promoter III indicated that an area between bp -152 to -107 contains the functional site of TncRNA. Conclusion Human TncRNA is active across species lines and significantly inhibits allogenic response to B-cells. There is concurrent suppression of constitutive class II expression in TncRNA clones mediated through a defined region of CIITA promoter III. |
| Databáze: | OpenAIRE |
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