イン・シット・クラス・スイッチングと,腸内膜のIgA産生細胞への差異化
S Fagarasan1, K Kinoshita, M Muramatsu
1Department of Medical Chemistry, Graduate School of Medicine, Kyoto University, Yoshida Konoe-cho, Sakyo-ku, Kyoto, 606-8501, Japan.
Nature
|October 26, 2001
まとめ
腸内膜は,IgMを発現するB細胞から免疫グロブリンA (IgA) プラズマ細胞を in situで生成する. このプロセスは,クラス・スイッチ・リコンビネーション (CSR) を含み,局所的に発生し,以前の移行理論に異議を唱える.
科学分野:
- 免疫学 免疫学とは
- 胃腸内科 胃腸内科
- 細胞生物学 細胞生物学
背景:
- 腸内粘膜は重要な免疫バリアであり,免疫グロブリンA (IgA) は腸内微生物群と食事中の抗原との相互作用を管理する上で重要な役割を果たします.
- 従来の理解では,IgAを産生する細胞はペイヤーのパッチから発生し,抗原刺激後に腸内膜に移動すると考えられている.
研究 の 目的:
- 腸内膜内におけるIgA生成細胞の起源と生成を調査する.
- 腸内におけるIgA+細胞発現における活性化誘発型シチジンデアミナーゼ (AID) とクラススイッチ再結合 (CSR) の役割を明らかにする.
主な方法:
- 野生型およびAID欠乏マウスからのB細胞の分析.
- AID発現とラミナプロピアB細胞における円形DNAトランスクリプトの評価.
- ラミナプロパティアB細胞とストロマ細胞によるin vitroおよびin vivo培養実験.
主要な成果:
- Lamina propriaのIgA+B細胞は,AIDとCSRに関連するトランスクリプトを発現し,最近のクラスチェンジを示しています.
- Lamina propriaでIgMを発現するB細胞は,IgA+の分化に先行しています.
- ラミナ・プロピア・ストロマル細胞との共培養は,IgA+プラズマ細胞とIgM+B細胞の差異化を促進する.
結論:
- 腸内膜のIgA+プラズマ細胞は,B220+IgM+リンパ球から局所的に生成されます.
- この in situ 生成プロセスは,レミナ・プロポリア内の継続的なクラス・スイッチ再組み合わせを含みます.
- この発見は,腸外部からIgA+細胞を誘導する伝統的なモデルに異議を唱えている.
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