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    Effector T Cell Responses

    $4.98
    18 Pages | 3,398 Words

    This book describes the activation and functions of effector T cells. We'll begin by discussing the different types of T cells, which are CD4+ and CD8+ T cells. Then, we'll move on to the specific functions of the different types and subtypes of T cells. We'll explore how different infections can induce T cell responses in different ways, and how this in turn affects the overall T cell-based immune response. This book is designed to be a convenient and concise resource regarding T cell activation and function.

    This book is ideal for undergraduate students majoring in biology or health sciences, as well as graduate and medical students interested in immunology.

    An Introduction to Effector T Cell Responses

    T cells are a type of immune lymphocyte that originate in the thymus and are involved primarily in adaptive or acquired immunity, however various subtypes play a role in innate immunity.

    T cells are an important part of the immune system. They provide immunity against a variety of different pathogens, including both extracellular and intracellular pathogens. T cells utilize many mechanisms to fight infections. CD4+ helper T cells produce cytokines to activate effector immune cells, such as CD8+ T cells, macrophages, B cells, and neutrophils. CD8+ T cells can directly kill infected cells. Although there are innate immune cells that can provide many of these functions, T cells provide the benefit of memory. When antigen is initially encountered, naïve T cells that recognize that antigen are activated and proliferate. After the infection is cleared, most of the activated T cells die, but a few remain and become memory cells. Upon re-infection, memory T cells quickly respond and are able to fight off the secondary infection more rapidly. Acquired immunity is an important part of protection against serious infections.

    T cells have a variety of different roles during infection. When a T cell is activated by antigen, a complex signaling cascade begins, which results in development of effector functions (Smith-Garvin, Koretzky, and Jordan 2009, 591-619). The cytokines present during activation and the presence of either a CD4 or CD8 co-receptor, influence the effector function a T cell will possess after activation.