The unique profile of cord blood natural killer cells balances incomplete maturation and effective killing function upon activation

Hum Immunol. 2012 Mar;73(3):248-57. doi: 10.1016/j.humimm.2011.12.015. Epub 2011 Dec 28.


Cord blood (CB) is increasingly used as a source of stem cells for hematopoietic stem cell transplantation, and natural killer (NK) cells may be the effectors of the antileukemic response observed after CB transplantation. Here, we analyzed the phenotype and functions of CB NK cell subsets. We determined that the percentage of NK cells was higher in CB compared with peripheral blood (PB). Furthermore, there was a higher percentage of the CD56(bright) subset in CB. CB NK cells reached a late stage of differentiation, but exhibited higher expression of NKG2A and expressed fewer killer-cell immunoglobulin-like receptors, suggesting an incomplete maturation. CB NK cells highly expressed CXCR4, but did not express L-selectin, highlighting unique homing properties of CB NK cells. CB NK cells proliferated in response to interleukin-2 and degranulated in response to stimulation with tumor cells, but failed to lyse K562 cells in (51)Cr-release assay. CB NK cells exhibited a lower interferon-γ production in comparison with PB NK cells. Culture with IL-2 increased CB NK cell functions. Our study sheds light on CB NK cell properties and highlights the potential of CB as a source of NK cells for immunotherapy.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Antigens, Neoplasm / immunology
  • CD56 Antigen / metabolism
  • Cell Differentiation
  • Cell Proliferation
  • Cells, Cultured
  • Cytotoxicity, Immunologic
  • Fetal Blood / cytology
  • Fetal Blood / immunology*
  • Hematopoietic Stem Cell Transplantation*
  • Humans
  • Immunophenotyping
  • Immunotherapy, Adoptive*
  • Interleukin-2 / immunology
  • Interleukin-2 / metabolism
  • Killer Cells, Natural / cytology
  • Killer Cells, Natural / immunology*
  • Lymphocyte Activation*
  • NK Cell Lectin-Like Receptor Subfamily C / metabolism
  • Receptors, CXCR4 / metabolism
  • Receptors, Lymphocyte Homing


  • Antigens, Neoplasm
  • CD56 Antigen
  • CXCR4 protein, human
  • Interleukin-2
  • NK Cell Lectin-Like Receptor Subfamily C
  • Receptors, CXCR4
  • Receptors, Lymphocyte Homing