概括
抗体通过结合抗原和激活补充来启动病原体的清除. 研究人员在抗体Fc区域中确定了特定的氨基酸 (Glu 318,Lys 320,Lys 322),这些氨基酸对C1q结合和补充激活至关重要.
科学领域:
- 免疫学 免疫学 免疫学
- 分子生物学分子生物学
- 生物化学 生物化学
背景情况:
- 抗体是幽默免疫的关键,通过补充溶解等机制调解病原体清除.
- 补体级联开始与C1q与抗体Fc区域结合,这种过程对离子强度敏感,并且在不同物种中保持.
- 最初的C1q与隔离的抗体Fc区域的结合是弱的,但多价值结合显著提高了亲和力.
研究的目的:
- 为了精确地绘制抗体Fc区域上的C1q结合部位.
- 为了确定参与C1q-抗体相互作用的特定氨基酸残留物.
- 为了研究已识别的结合部位在补剂激活中的功能意义.
主要方法:
- 在小鼠IgG2b同型中的表面残留物的系统性突变发生.
- 对C1q与改变的抗体变体的结合 afinities 的分析.
- 测试一种模仿已识别的结合部位的有效性,以抑制补体溶解.
主要成果:
- 在小鼠IgG2b Fc区域定位了C1q结合点到三个特定的侧链:Glu 318,Lys 320和Lys 322.
- 这些残留物保留在其他抗体同型体中.
- 一种模仿这种序列基因的酸有效地抑制了补体溶解.
结论:
- 识别的序列基因 (Glu 318,Lys 320,Lys 322) 是 IgG 抗体上 C1q 的关键结合部位.
- 这种保存的图案对于启动古典补充路径至关重要.
- 这些发现为C1q抗体相互作用和潜在的治疗向提供了分子基础.
相关概念视频
01:10Antibody Structure
Overview
Antibodies, also known as immunoglobulins (Ig), are essential players of the adaptive immune system. These antigen-binding proteins are produced by B cells and make up 20 percent of the total blood plasma by weight. In mammals, antibodies fall into five different classes, which each elicits a different biological response upon antigen binding.
The Y-Shaped Structure of Antibodies Consists of Four Polypeptide Chains
Antibodies consist of four polypeptide chains: two identical heavy...
Antibodies, also known as immunoglobulins (Ig), are essential players of the adaptive immune system. These antigen-binding proteins are produced by B cells and make up 20 percent of the total blood plasma by weight. In mammals, antibodies fall into five different classes, which each elicits a different biological response upon antigen binding.
The Y-Shaped Structure of Antibodies Consists of Four Polypeptide Chains
Antibodies consist of four polypeptide chains: two identical heavy...
01:10Antibody Structure
Overview
Antibodies, also known as immunoglobulins (Ig), are essential players of the adaptive immune system. These antigen-binding proteins are produced by B cells and make up 20 percent of the total blood plasma by weight. In mammals, antibodies fall into five different classes, which each elicits a different biological response upon antigen binding.
The Y-Shaped Structure of Antibodies Consists of Four Polypeptide Chains
Antibodies consist of four polypeptide chains: two identical heavy...
Antibodies, also known as immunoglobulins (Ig), are essential players of the adaptive immune system. These antigen-binding proteins are produced by B cells and make up 20 percent of the total blood plasma by weight. In mammals, antibodies fall into five different classes, which each elicits a different biological response upon antigen binding.
The Y-Shaped Structure of Antibodies Consists of Four Polypeptide Chains
Antibodies consist of four polypeptide chains: two identical heavy...
01:15Transcytosis of IgG
Transcytosis is the process in which molecules are internalized by endocytosis, transported across the cell, and released through exocytosis from the opposite end of the cell. Molecules such as insulin, immunoglobulins, and certain nutrients are transferred through the recycling endosomes by recycling and transcytosis.
IgG molecules from a mother undergo transcytosis starting around 13 weeks of gestation. The amount of IgG transferred and entering the fetal blood circulation increases with...
IgG molecules from a mother undergo transcytosis starting around 13 weeks of gestation. The amount of IgG transferred and entering the fetal blood circulation increases with...
01:31Immunoglobulin-like Cell Adhesion Molecules
Immunoglobulin-like cell adhesion molecules or Ig-CAMs are a versatile group of cell surface glycoproteins belonging to the immunoglobulin protein superfamily. Ig-CAMs possess the characteristic immunoglobulin protein domains and other domains such as the fibronectin type III domain. The Ig domains are glycosylated to varying degrees in different Ig-CAMs.
Ig-CAMs exhibit either homophilic binding (to other Ig-CAMs) or heterophilic binding (to other ligands such as integrins). While most Ig-CAMs...
Ig-CAMs exhibit either homophilic binding (to other Ig-CAMs) or heterophilic binding (to other ligands such as integrins). While most Ig-CAMs...
01:22Immunocytochemistry and Immunohistochemistry
Immunocytochemistry (ICC) and immunohistochemistry (IHC) are techniques that use antibodies to check for specific proteins or antigens in a sample. The technique was first published by Albert Coons in 1941 to detect the presence of pneumococcal antigen in tissue sections from mice infected with Pneumococcus. Immunocytochemistry helps localization of proteins or antigens in individual cells like blood cells, stem cells, etc., while immunohistochemistry does the same for tissue samples.
These...
These...
01:25Antibody Structure and Classes
Antibodies, also known as immunoglobulins, are produced by B cells in response to foreign substances, such as bacteria and viruses. These proteins are critical for recognizing and neutralizing these substances, protecting the body from potential harm.
The basic structure of an antibody consists of four protein chains: two identical heavy chains and two identical light chains. These chains are held together by disulfide bonds and other non-covalent interactions, forming a Y-shaped structure.
The basic structure of an antibody consists of four protein chains: two identical heavy chains and two identical light chains. These chains are held together by disulfide bonds and other non-covalent interactions, forming a Y-shaped structure.