Soluble HLA-G dampens CD94/NKG2A expression and function and differentially modulates chemotaxis and cytokine and chemokine secretion in CD56bright and CD56dim NK cells

Blood. 2011 Nov 24;118(22):5840-50. doi: 10.1182/blood-2011-05-352393. Epub 2011 Oct 11.

Abstract

Soluble HLA-G (sHLA-G) inhibits natural killer (NK) cell functions. Here, we investigated sHLA-G-mediated modulation of (1) chemokine receptor and NK receptor expression and function and (2) cytokine and chemokine secretion in CD56bright and CD56dim NK cells. sHLA-G-treated or untreated peripheral blood (PB) and tonsil NK cells were analyzed for chemokine receptor and NK receptor expression by flow cytometry. sHLA-G down-modulated (1) CXCR3 on PB and tonsil CD56bright and CD56dim, (2) CCR2 on PB and tonsil CD56bright, (3) CX3CR1 on PB CD56dim, (4) CXCR5 on tonsil CD56dim, and (5) CD94/NKG2A on PB and tonsil CD56brigh) and CD56dim NK cells. Such sHLA-G-mediated down-modulations were reverted by adding anti-HLA-G or anti-ILT2 mAbs. sHLA-G inhibited chemotaxis of (1) PB NK cells toward CXCL10, CXCL11, and CX3CL1 and (2) PB CD56bright NK cells toward CCL2 and CXCL10. IFN-γ secretion induced by NKp46 engagement was inhibited by NKG2A engagement in untreated but not in sHLA-G-treated NK cells. sHLA-G up-regulated secretion of (1) CCL22 in CD56bright and CD56dim and (2) CCL2, CCL8, and CXCL2-CXCL3 in CD56dim PB NK cells. Signal transduction experiments showed sHLA-G-mediated down-modulation of Stat5 phosphorylation in PB NK cells. In conclusion, our data delineated novel mechanisms of sHLA-G-mediated inhibition of NK-cell functions.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • CD56 Antigen / metabolism*
  • Cells, Cultured
  • Chemokines / metabolism*
  • Chemotaxis, Leukocyte / drug effects*
  • Cytokines / metabolism*
  • Down-Regulation / drug effects
  • Flow Cytometry
  • HLA-G Antigens / chemistry
  • HLA-G Antigens / pharmacology*
  • Humans
  • Killer Cells, Natural / drug effects*
  • Killer Cells, Natural / metabolism
  • Killer Cells, Natural / physiology
  • NK Cell Lectin-Like Receptor Subfamily C / metabolism*
  • NK Cell Lectin-Like Receptor Subfamily C / physiology
  • NK Cell Lectin-Like Receptor Subfamily D / metabolism*
  • NK Cell Lectin-Like Receptor Subfamily D / physiology
  • Osmolar Concentration
  • Protein Isoforms / pharmacology
  • Solubility

Substances

  • CD56 Antigen
  • Chemokines
  • Cytokines
  • HLA-G Antigens
  • KLRD1 protein, human
  • NK Cell Lectin-Like Receptor Subfamily C
  • NK Cell Lectin-Like Receptor Subfamily D
  • Protein Isoforms