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Other Cell Types

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Dendritic Cells

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Summary

Dendritic cells are professional antigen-presenting cells that sample their environment for antigens to present to T-cells. Since they constitutively express MHC II and B7, they are the most effective antigen presenters. Dendritic cells in the skin are specifically called Langerhans cells, and these Langerhans cells have tennis-racquet shaped granules called Birbeck granules.

Key Points

  • Dendritic Cells
    • Professional antigen-presenting cells (APCs)
      • Constitutively express MHC II and B7
      • Sample their environment for antigens to present
      • Link the innate and adaptive immune responses
    • Called Langerhans cells in skin (e.g. Langerhans cell histiocytosis)
      • Contain Birbeck granules
        • tennis-racket shaped intracytoplasmic granules on EM
    • Stain S-100 positive