The Function of Tuftsin and Similar Sequences in Other Proteins
The Function of Tuftsin and Similar Sequences in Other Proteins
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Tuftsin 和其他蛋白质中类似序列的功能
DOI：
10.1111/j.1749-6632.1983.tb37102.x
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发表时间：
1983
影响因子：
5.2
通讯作者：
M. Feldman
中科院分区：
文献类型：
--
作者：
S. Segal;E. Tzehoval;M. Feldman
免疫球蛋白分子是许多动物免疫防御机制的重要组成部分。除了一个特定的活性结合位点外，它还具有调节细胞活性、分化和迁移的能力。这是通过与Ruids中的各种可溶性成分相互作用来实现的，例如直接与能够识别Ig分子的特定立体特异性构象的特定细胞表面受体相互作用（参见参考文献3）。对这些相互作用的分子基础的研究表明，所有这些活性都局限于进化上保存的lg分子的恒定区域（Fc）。这些决定因子的特异性识别受体被定义为Fc受体。这些受体，通过Ig分子发挥其调节功能，发现在许多细胞类型。因此，在几乎所有的吞噬细胞、T细胞、B细胞、NK肿瘤细胞和许多病毒感染细胞上都可以找到这样的受体。fc相关决定因素通过这些受体发出的信号可能导致这些细胞发挥效应功能，并导致其克隆扩增和分化。这些功能可以通过游离的Ig分子或其分离的Fc片段，或抗原-抗体激活的构象改变的免疫复合物来完成。这可以解释免疫复合物的免疫调节功能，以及这些复合物与补体对不同组织和器官造成严重损伤的机制，从而导致免疫复合物引起的疾病为了阐明Fc部分发挥其效应功能的调控机制，研究人员发现该片段或来自该部分的几个肽可能调节巨噬细胞和T细胞依赖性B细胞的增殖和效应功能。~’~正如Berman等人以及Morgan和weigle所发现的，Fc片段调节淋巴细胞增殖和分化的能力并不仅仅局限于B细胞，它也可能调节其他淋巴细胞亚群（即T淋巴细胞）的增殖、分化和Fc受体的形成。由此证明，IgA的Fc部分可能导致T细胞显示T- α受体的特定亚群的频率增加。这些细胞参与IgA合成的调控，并参与这些细胞上IgA Fc受体密度的增加大量的Fc受体可能在这些细胞附近脱落。这一发现具有进一步的意义
The immunoglobulin molecule is a major component of the immune defense mechanism of many animal species. It possesses, it addition to a specific active binding site, the ability to regulate the activity, differentiation, and migration of cells. This is achieved by interacting either with various soluble components in the Ruids, such as or directly with specific cell-surface receptors capable of recognizing a defined stereospecific conformation of the Ig molecule (reviewed in ref. 3). The investigation of the molecular basis of these interactions revealed that all these activities were confined to the evolutionarily preserved constant region of the lg molecule (Fc). The specific recognizing receptors for these determinants are defined as Fc receptors. These receptors, through which the Ig molecule exerts its regulatory function, are found on many cell types. Thus, one can find such receptors on almost all phagocytic cells, T cells, B cells,’ NK tumor cells and many virally infected cells. Signals exerted by Fc-associated determinants through these receptors may lead to the elicitation of effector functions exerted by such cells and to their clonal expansion and differentiation. These functions can be performed either by free Ig molecules, or their isolated Fc fragments, or by antigen-antibody-activated, conformationally changed immune complexes. This may explain the immunoregulatory functions of immune complexes and the mechanisms by which these complexes with complement cause severe injuries to different tissues and organs, thus being responsible for diseases invoked by immune complexes.6 In an effort to elucidate the regulatory mechanism by which the Fc portion exerts its effector functions, it was found that this fragment or several peptides derived from this portion may regulate the proliferation and effector functions of macrophages and T cell-dependent B cell a~ t iva t ion .~’~ The ability of Fc fragments to regulate the proliferation and differentiation of lymphocytes is not exclusively confined to B cells, as found by Berman et aL7*’ and Morgan and Weigle.9-12 It may also regulate the proliferation, differentiation, and Fc-receptor formation of additional subsets of lymphocytes, that is, T lymphocytes. It was thus demonstrated that the Fc portion of IgA may cause an increase in the frequency of specific subsets of T cells displaying the T-alpha receptor. These cells are involved in the regulation of IgA synthesis” and in the increased density of Fc receptors for IgA on these cells.14 A significant number of these Fc receptors may be shed in the vicinity of these cells. This finding gains further significance in view of the
胸腺生成素与免疫球蛋白和细胞识别分子的进化关系。
DOI：
--
发表时间：
1981
期刊：
Journal of immunology (Baltimore, Md. : 1950)
影响因子：
--
作者：
Hahn,GS;Hamburger,RN
通讯作者：
Hamburger,RN