Section outline

  • A group of T cells attacking a cancer cell in a blood-like environment.

    Do cells really attack other cells?
    ::细胞真的会攻击其他细胞吗 ?

    They sure do. Depicted here is a group of T cells attacking a . When they can, the T cells search out and destroy “bad” cells.
    ::他们当然知道,这里最引人注意的是一组T型细胞攻击一个T型细胞。如果能够,T型细胞会搜索并摧毁“坏”细胞。

    Cell-Mediated Immune Response
    ::细胞调节免疫反应

    In addition to the , the other type of immune response is the cell-mediated immune response , which involves mainly T cells . It leads to the destruction of cells that are infected with . Some cancer cells are also destroyed in this way. There are several different types of T cells involved in a cell-mediated immune response, including helper, cytotoxic, and regulatory T cells
    ::除此以外,另一种类型的免疫反应是细胞介质的免疫反应,这主要涉及T细胞,导致被感染的细胞被摧毁。有些癌症细胞也以这种方式被摧毁。在细胞介质的免疫反应中,有几种不同类型的T细胞,包括助手、细胞毒性和管制T细胞。

    T Cell Activation
    ::T 细胞激活

    All three types of T cells must be activated by an antigen before they can fight an infection or cancer. T cell activation is illustrated in Figure . It begins when a B cell or nonspecific leukocyte engulfs a virus and displays its antigens. When the T cell encounters the matching antigen on a leukocyte, it becomes activated. What happens next depends on which type of T cell it is.
    ::所有三种T型细胞都必须先用抗原来激活,然后才能对抗感染或癌症。T型细胞激活在图中说明。当B型细胞或非特定白血球吞没病毒并展示其抗原时,T型细胞就开始激活。当T型细胞在白血球上遇到匹配的抗原时,它就会被激活。接下来会发生什么取决于T型细胞是哪种类型。

    T cell activation process showing antigen presentation and resulting activated helper and cytotoxic T cells.

    T cell activation requires another leukocyte to engulf a virus and display its antigen.
    ::T细胞激活需要另一种白血球来吞没病毒并展示其抗原。

    Helper T Cells
    ::帮助 T 单元格

    Helper T cells are like the “managers” of the immune response. They secrete cytokines , which activate or control the activities of other lymphocytes . Most helper T cells die out once a has been cleared from the body, but a few remain as memory cells . These memory cells are ready to produce large numbers of antigen-specific helper T cells like themselves if they are exposed to the same antigen in the future.
    ::帮助T细胞就像免疫反应的“管理者 ” 。 它们会将激活或控制其他淋巴细胞活动的细胞外科细胞分离出来。 大部分帮助T细胞一旦从身体中清除出来就会死亡,但有少数仍然作为记忆细胞存在。 这些记忆细胞准备产生大量的抗原特有T细胞,如果它们将来接触同样的抗原的话,它们也会像自己一样产生大量的抗原特有T细胞。

    Cytotoxic T Cells
    ::Cyto毒性T细胞

    Cytotoxic T cells destroy virus-infected cells and some cancer cells. Once activated, a cytotoxic T cell divides rapidly and produces an “army” of cells identical to itself. These cells travel throughout the body “searching” for more cells to destroy. Figure shows how a cytotoxic T cell destroys a body cell infected with viruses. This T cell releases toxins that form pores in the membrane of the infected cell. This causes the cell to burst, destroying both the cell and the viruses inside it.
    ::细胞毒性T细胞会摧毁感染病毒的细胞和一些癌症细胞,一旦激活,细胞毒性T细胞会迅速分裂,产生与自己相同的细胞“军团”,这些细胞会“搜索”整个身体,以便摧毁更多的细胞。图示显示细胞毒性T细胞如何摧毁感染病毒的细胞。这个T细胞会释放毒素,形成受感染细胞的膜孔。这会导致细胞破裂,摧毁细胞和体内的病毒。

    Cytotoxic T cells attacking infected cells, leading to cell and virus destruction.

    A cytotoxic T cell releases toxins that destroy an infected body cell and the viruses it contains.
    ::细胞毒性T细胞释放毒素,摧毁受感染的身体细胞及其所含病毒。

    After an infection has been brought under control, most cytotoxic T cells die off. However, a few remain as memory cells. If the same pathogen enters the body again, the memory cells mount a rapid immune response. They quickly produce many copies of cytotoxic T cells specific to the antigen of that pathogen.
    ::在控制了感染后,大多数细胞毒性T细胞死亡,但少数细胞仍作为内存细胞存在。如果同样的病原体再次进入体内,内存细胞将产生快速的免疫反应。它们会很快产生许多该病原体抗原特有的细胞毒性T细胞。

    Regulatory T Cells
    ::监管T 单位

    Regulatory T cells are responsible for ending the cell-mediated immune response after an infection has been curbed. They also suppress T cells that mistakenly react against self antigens. What might happen if these T cells were not suppressed?
    ::监管T型细胞负责在抑制了感染后终止细胞中介的免疫反应,还抑制了对自我抗原产生错误反应的T型细胞。 如果不抑制T型细胞,会发生什么情况?

       

     

    Summary
    ::摘要

    • Activated T cells destroy certain cancer cells and cells infected by viruses.
      ::激活的T型细胞摧毁了某些癌症细胞和受病毒感染的细胞。
    • Memory T cells remain in the body after the immune response and provide antigen-specific immunity to the virus.
      ::内存T细胞在免疫反应后留在体内,对病毒提供抗原特有免疫。

    Review
    ::回顾

    1. Describe one way that cytotoxic T cells destroy cells infected with viruses.
      ::用一种方式描述细胞毒性T细胞摧毁感染病毒的细胞。
    2. What are regulatory T cells?
      ::什么是监管T小组?

    Resources
    ::资源