Activation and Function of Unconventional T Cells

  • Walter Gottlieb Land


Efferent innate immune responses include the function of unconventional T cells with partial innate properties. While most studies of T lymphocytes have focused on T cells involved in adaptive immune responses by reacting to complexes of peptide and major histocompatibility complex proteins, many other types of T cells do not match this paradigm. As described in this chapter, these cells include CD1-restricted natural killer T cells, MR1-restricted mucosal-associated invariant T cells, and gammadelta T cells. Collectively, these T cells are considered unconventional, in part, because they exert partial innate functions and in part because they can recognize non-classical/non-peptide antigens such as lipids, small-molecule metabolites, and specially modified peptides. Unlike conventional T cells, these unconventional T cells are characterized by semi-invariant, invariant, or even germline-encoded T cell receptors which mediate rapid effector responses. Here, evidence in the perspective of the book is reviewed showing that unconventional T cells are not only activated by recognition of cognate antigens but also—directly or indirectly—by various classes of DAMPs emitted during infectious and sterile injury or exposed by transformed malignant cells. In addition, examples of the various efferent functions of unconventional T cells are briefly addressed pointing to their impressive role in orchestrating and regulating immune responses in infectious and sterile inflammation and tumor surveillance.


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© Springer International Publishing AG, part of Springer Nature 2018

Authors and Affiliations

  1. 1.University of StrasbourgMolecular ImmunoRheumatology, Laboratory of Excellence TransplantexStrasbourgFrance

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