アンチゲン誘発のB細胞死と,生殖中心の免疫反応の間に発生する B細胞の消去
1Howard Hughes Medical Institute, Stanford University School of Medicine, California 94305, USA.
Nature
|May 25, 1995
まとめ
研究者は,自己反応性細胞がどのように排除されるかを理解するために,生殖中心 (GCs) のB細胞の反応を視覚化しました. 彼らは,抗原を投与すると,これらのB細胞でアポトーシスを誘発し,オートアンチボディの生成を防ぐことを発見しました.
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.
- 細胞生物学 細胞生物学
背景:
- 免疫反応の間,生殖中心 (GCs) のB細胞は,高親和性抗体を作るため,ハイパーミューテーションを経験します.
- 自己反応性B細胞は,この段階で排除されると考えられていますが,直接分析は,その希少性とダイナミックなGC環境のために困難でした.
研究 の 目的:
- GC内の抗原特異B細胞の運命を視覚化するための新しい方法を開発する.
- GC応答中の自己反応性B細胞除去のメカニズムを調査する.
主な方法:
- リゾーシム特異のB細胞を持つ免疫グロブリン遺伝子トランスジェニック動物を使用した.
- 進行中の免疫反応をこれらのトランスジェニックB細胞でシードした.
- GC反応のピークに溶解性抗原を投与してアポトーシスを誘発する.
主要な成果:
- ライソ酵素特異のGCB細胞は,抗原投与後,アポトーシスの2つの波で急速に除去されました.
- アポトーシスは,GC内および,T細胞に富んだリンパ性ゾーンに移住したB細胞の両方で発生しました.
- bcl-2の構成表現は,これらの自己反応性B細胞の除去を阻害しました.
結論:
- 自身抗体の親和性成熟を防ぐGC反応における重要な検閲ステップを特定した.
- これらの発見は,病原性微生物が免疫反応を回避する方法を理解し,抗体生成を調節する臨床戦略を開発するための意味を持つ.
関連する概念動画
01:40Cell-mediated Immune Responses
Overview
01:36Humoral Immune Responses
Overview
01:20Special Features of Adaptive Immunity
The adaptive immune system, a crucial component of the overall immune response, offers a highly specialized defense against pathogens. It involves specific cell types and features, enabling it to combat infections effectively and efficiently.
The primary cell types involved in adaptive immunity are T cells and B cells. Each type has a unique role in defending the body against pathogens. T cells are responsible for cell-mediated immunity. They identify and eliminate infected cells directly,...
The primary cell types involved in adaptive immunity are T cells and B cells. Each type has a unique role in defending the body against pathogens. T cells are responsible for cell-mediated immunity. They identify and eliminate infected cells directly,...
01:23Cells of the Adaptive Immune Response
The T and B lymphocytes of the adaptive immune system develop from common lymphoid progenitor cells in the bone marrow. These progenitors give rise to precursors that eventually develop into both T and B lymphocytes. As these precursors mature, they gain the ability to detect and respond to foreign antigens in the body, a process known as immunocompetence. Additionally, these precursors acquire self-tolerance, a process that ensures they do not react to self-antigens. This intricate system...
01:27Cytotoxic T Cells-mediated Immune Response
Cytotoxic T cells are a vital component of the immune system. They have the remarkable ability to identify and target antigens on infected or abnormal cells. These antigens often originate from intracellular pathogens such as viruses or abnormal proteins cancer cells produce.
Immunological surveillance is the ability of immune cells to monitor and eliminate infected cells with intracellular pathogens, neoplastically transformed cells, and cells with non-self antigens. Cytotoxic T cells and NK...
Immunological surveillance is the ability of immune cells to monitor and eliminate infected cells with intracellular pathogens, neoplastically transformed cells, and cells with non-self antigens. Cytotoxic T cells and NK...
01:24B Cell Activation and Differentiation
The adaptive immune response, a sophisticated defense mechanism, relies on the activation and differentiation of B lymphocytes, or B cells. These processes enable our bodies to mount a tailored response against specific pathogens such as bacteria, free virus particles, toxins, and parasites.
When naive B cells encounter a specific antigen that can bind to the B cell receptor (BCR) on their surface, they undergo sensitization to respond to the antigen's presence. Sensitization begins with...
When naive B cells encounter a specific antigen that can bind to the B cell receptor (BCR) on their surface, they undergo sensitization to respond to the antigen's presence. Sensitization begins with...