T lymphocyte recognition of human group 1 CD1 molecules: implications for innate and acquired immunity

Semin Immunol. 2000 Dec;12(6):511-6. doi: 10.1006/smim.2000.0277.


Recent evidence has established that non-MHC-encoded molecules of the CD1 family mediate MHC-independent pathways for antigen presentation and T cell activation. Human group 1 CD1 molecules (CD1a, CD1b, CD1c) are expressed mainly on professional antigen-presenting cells, and mediate presentation of microbial lipid and glycolipid antigens to T cells. These group 1 CD1 molecules differentially sample distinct endocytic compartments that may contain different sets of lipid antigens derived from intracellular microbes, and activate antigen-specific T cells. These T cells lyse infected antigen-presenting cells and secrete Th1 cytokines, such as interferon- gamma, and granulysin, a potent antimicrobial protein, and thus can control microbial infection. Reactivity to CD1a, b, and c molecules in the absence of foreign antigen has also been detected in T cells bearing alphabeta and gammadelta TCRs. These T cells may recognize self-lipid antigens and are considered to be autoreactive. In particular, the main tissue subset of gammadelta T cells (V delta 1(+)subset) show prominent reactivity to CD1c, and produce interferon- gamma and granulysin. These CD1c directly reactive T cells may mediate immunity against microbial infection even before antigen-specific T cells differentiate and expand. Together, human CD1a, b and c molecules elicit T cell-dependent immunity to the universe of foreign and self-lipid antigens in both innate and acquired immunity settings.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.
  • Review

MeSH terms

  • Animals
  • Antigen Presentation / immunology*
  • Antigens, CD1 / metabolism*
  • Humans
  • Immunity, Active*
  • Immunity, Innate*
  • Lymphocyte Activation / immunology
  • T-Lymphocytes / immunology*
  • T-Lymphocytes / metabolism*


  • Antigens, CD1