リンパ性細胞のT細胞とB細胞の抗原受容体を通じたシグナル伝達に欠陥があり,その細胞にVAV原発がん遺伝子が欠けている
1Division of Hematology/Oncology, Children's Hospital, Boston, Massachusetts 02115, USA.
Nature
|March 30, 1995
まとめ
vav原発がん遺伝子は,T細胞とB細胞の発達と活性化に不可欠です. 欠乏すると免疫不全が生じ,免疫細胞の信号伝達と機能におけるその役割を強調する.
科学分野:
- 免疫学 免疫学とは
- 分子生物学は分子生物学である.
- 腫瘍遺伝子 (オンコゲネス) とは
背景:
- vavプロトオンコゲン産物であるp95vav (Vav) は,受容体刺激によりT細胞とB細胞でチロシンがリン酸化される.
- Vavには,信号伝達経路における役割を示唆するモチーフが含まれています.
研究 の 目的:
- T細胞とB細胞の発達と活性化におけるvAV遺伝子のインビボ機能を解明する.
- 免疫細胞集団と免疫応答に対するVAV欠乏の影響を調査する.
主な方法:
- 遺伝子の欠乏モデルを作成するために,利用されたv-gene-targeted胚性幹細胞.
- ブラストシスト補充によるRAG-2-/-を用い,バブ・ラグ-2-/-キメラを生成した.
- T細胞とB細胞の集団,胸膜の構造,様々な刺激に対する細胞の反応を評価した.
主要な成果:
- ヴァーブ欠乏キメラは,胸膜縮と外周T細胞の減少を示した.
- 通常のB細胞総数にもかかわらず,腹膜B-1 (CD5+) 細胞の完全な欠如が観察されました.
- Vav欠乏のT細胞とB細胞は,抗原受容体刺激に対する低活性性を示した.
- Vav欠乏性T細胞は,ホルボールエステルとイオノフォールカルシウムによる刺激で増殖した.
- Vav欠乏B細胞は,細菌のミトゲンおよびCD40リガンド刺激に正常に反応した.
結論:
- T細胞とB細胞の発達を調節する vavの重要なin vivo役割が確立された.
- vavは,適切なT細胞とB細胞の活性化と,抗原受容体を通じたシグナル伝達に不可欠であることを示した.
- 腹腔内B-1細胞の発達のための vavの特定の要件を強調しました.
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