Activated gammadelta T cells express the natural cytotoxicity receptor natural killer p 44 and show cytotoxic activity against myeloma cells

Clin Exp Immunol. 2006 Jun;144(3):528-33. doi: 10.1111/j.1365-2249.2006.03078.x.


gammadelta T cells account for up to 10% of T lymphocytes in the peripheral blood of healthy donors. They can be activated by cytokines such as interleukin (IL)-2, IL-12 and IL-15, express natural killer (NK) cell markers such as NKG2D and show cytotoxic activity against several tumour cells, including multiple myeloma. Here, we present activated polyclonal gammadelta T cells from healthy donors with an NK T cell-like phenotype expressing the natural cytotoxicity receptor NKp44. Natural cytotoxicity receptors NKp30, NKp44 and NKp46 have been regarded as specific NK receptors; only two gammadelta T cell clones described so far expressed NKp 44. Isolated polyclonal gammadelta T cells cultured for 7 days according to the cytokine-induced killer cell (CIK) protocol with additional IL-15 revealed a surface expression of NKp44 of 8+/-7% (n=22). This could be confirmed by detection of NKp 44 mRNA by reverse transcription-polymerase chain reaction (RT-PCR). gammadelta T cells exhibited a marked cytotoxic activity against myeloma cells, which could be reduced by inhibition of NKp44. To our knowledge, this is the first description of the expression of NKp44 on polyclonal gammadelta T cells.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Cells, Cultured
  • Cytotoxicity, Immunologic*
  • Gene Expression Regulation / immunology
  • Humans
  • Immunophenotyping
  • Interleukin-15 / immunology
  • Interleukin-2 / immunology
  • Killer Cells, Natural / immunology*
  • Lymphocyte Activation
  • Multiple Myeloma / immunology
  • Multiple Myeloma / pathology*
  • Natural Cytotoxicity Triggering Receptor 2
  • RNA, Messenger / genetics
  • Receptors, Antigen, T-Cell, gamma-delta / analysis*
  • Receptors, Immunologic / genetics
  • Receptors, Immunologic / metabolism*
  • Reverse Transcriptase Polymerase Chain Reaction / methods
  • Tumor Cells, Cultured


  • Interleukin-15
  • Interleukin-2
  • NCR2 protein, human
  • Natural Cytotoxicity Triggering Receptor 2
  • RNA, Messenger
  • Receptors, Antigen, T-Cell, gamma-delta
  • Receptors, Immunologic