title: Interleukin (IL)-15 in combination with IL-2, fms-like tyrosine kinase-3 ligand and anti-CD3 significantly enhances umbilical cord blood natural killer (NK) cell and NK-cell subset expansion and NK function.
abstract: OBJECTIVE
  Interleukin (IL)-15 and fms-like tyrosine kinase-3 (FLT-3) are crucial factors for the development of human and murine natural killer (NK) cells. Previously, we have demonstrated significant ex vivo expansion and activation of unrelated cord blood (UCB) NK cells with an antibody/cytokine cocktail consisting of anti-CD3 + IL-2 + IL-12 + IL-7 and anti-CD3 + IL-2 + IL-12 + IL-18.
  
  
  METHODS
  In the current experiments, we investigated the effects of short-term culture with anti-CD3 + IL-2 + FLT-3 + IL-15 on cord blood (CB) NK cell and NK-cell subset expansion and function. CB mononuclear cells were cultured for 48 h in AIM-V media or AIM-V + IL-2 (5 ng/mL) + anti-CD3 (50 ng/mL) + FLT-3 (50 ng/mL) ± escalating doses of IL-15 (1, 10 or 100 ng/mL). Flow cytometric analysis was performed using various fluorescent-conjugated monoclonal antibodies. In vitro cytotoxicity was determined with a standard europium assay against K562 and Daudi cells.
  
  
  RESULTS
  There was a 4.8-fold significant increase in NK-cell population (CD3(-)/16(+)/56(+); P < 0.03), 21-fold significant increase in CD3(-)/56(+)/158a(+) (KIR2DL1/S1; P < 0.002), 46-fold significant increase in CD3(-)/56(+)/158b(+) (KIR2DL1/S2; P < 0.002) and 11.5-fold significant increase in CD3(-)/56(+)/NKB1(+) (KIR3DL1; P < 0.01). We also noted a significant increase in both NK and lymphokine-activated killer (LAK) cytotoxicity with IL-2 + anti-CD3 + FLT-3 + IL-15 (100 ng/mL) compared with IL-2 + anti-CD3 + FLT-3 and media alone against K562 (P < 0.01) and Daudi (P < 0.001), respectively.
  
  
  CONCLUSIONS
  We have demonstrated a significant increase in UCB NK cells and NK cells expressing a variety of killer immunoglobulin-like receptor (KIR) receptors after short-term culture with anti-CD3, IL-2, FLT-3 and IL-15. Furthermore, there was a significant increase in in vitro NK/LAK cell cytotoxicity.
authors.affiliation: Department of Pediatrics, Columbia University, New York, New York 10032, USA.
authors.forename: Prakash
authors.initials: P
authors.lastname: Satwani
authors.forename: Carmella
authors.initials: C
authors.lastname: van de Ven
authors.forename: Janet
authors.initials: J
authors.lastname: Ayello
authors.forename: Dustin
authors.initials: D
authors.lastname: Cairo
authors.forename: Lynn L
authors.initials: LL
authors.lastname: Simpson
authors.forename: Laxmi
authors.initials: L
authors.lastname: Baxi
authors.forename: Mitchell S
authors.initials: MS
authors.lastname: Cairo
mesh_terms: D017209:Apoptosis / Q000187:drug effects; D002460:Cell Line; D002470:Cell Survival / Q000187:drug effects; D005312:Fetal Blood / Q000166:cytology*; D005434:Flow Cytometry; D006801:Humans; D019409:Interleukin-15 / Q000494:pharmacology*; D007376:Interleukin-2 / Q000494:pharmacology*; D007694:Killer Cells, Natural / Q000166:cytology* / Q000187:drug effects*; D016853:Muromonab-CD3 / Q000494:pharmacology*; D051941:fms-Like Tyrosine Kinase 3 / Q000494:pharmacology*
chemical_list: D019409:Interleukin-15; D007376:Interleukin-2; D016853:Muromonab-CD3; D051941:fms-Like Tyrosine Kinase 3