ATP結合カセットトランスポーターとHDLは,造血幹細胞の増殖を抑制する
Laurent Yvan-Charvet1, Tamara Pagler, Emmanuel L Gautier
1Division of Molecular Medicine, Department of Medicine, Columbia University, New York, NY 10032, USA. ly2159@columbia.edu
まとめ
ABCA1およびABCG1トランスポーターが欠けているマウスは,白血球と幹細胞の増加を示し,病気を誘発しました. 高密度脂質タンパク質 (HDL) のレベルを回復させることで,これらの効果は逆転し,コレステロールの輸送と血液細胞の増殖との関連が示唆された.
科学分野:
- 心血管生物学 心血管生物学
- ヘマトポエーシス (血液形成) とは
- 動脈硬化症の研究研究
背景:
- 白血球症,特に単細胞症は,動脈硬化症と関連しています.
- 白血球数の増加を誘発するメカニズムは不明である.
- アデノシン三酸塩結合カセット (ABC) トランスポーターABCA1とABCG1は,マクロファージからのコレステロール流出と動脈硬化抑制に不可欠です.
研究 の 目的:
- ABCA1とABCG1が血液生成幹細胞と祖先細胞の集団を調節する役割を調査する.
- ABCトランスポーター,白血球症,動脈硬化症の発達との関連を理解する.
主な方法:
- ABCA1とABCG1.1に欠陥のあるマウスの生成と分析.
- 骨髄移植実験 骨髄移植実験について
- 造血幹細胞と原始細胞集団 (LSK) の評価.
- 白血球症,骨髄増殖性疾患,動脈硬化症の評価.
主要な成果:
- ABCA1およびABCG1が欠けていたマウスは,骨髄増殖性疾患である白血球症と,Lin(-) Sca-1(+) Kit+ (LSK) 幹細胞および原始細胞の膨張を示した.
- Abca1(-/-)Abcg1(-/-) 骨髄を高密度リポプロテイン (HDL) トランスジェニックマウスに移植することで,LSKの膨張と白血球症が抑制されました.
- この移植はまた,骨髄増殖障害を逆転させたが,動脈硬化症を加速させた.
結論:
- ABCA1,ABCG1,およびHDLは,血液形成性幹細胞および多潜在的原始細胞の増殖に重要な抑制的役割を果たします.
- これらの幹細胞および原始細胞集団の拡大は,白血球症および加速性動脈硬化症と直接関連しています.
- これらの発見は,コレステロール流出経路と,動脈硬化症の文脈で血液細胞生産の調節との間の新しい関連性を確立しています.
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