title: Multivariate statistical data analysis as a tool to analyze ex vivo expansion dynamics of cytokine-induced killer cells.
abstract: BACKGROUND
  Cytokine-induced killer (CIK) cells, obtained after mononucleated cell stimulation with interferon-γ, interleukin-2, and anti-CD3 antibody, are constituted by CD3(+) CD56(+) (CIK) cells and a minority of natural killer (NK; CD3(-) CD56(+) ) cells and T-lymphocytes (CD3(+) CD56(-) ) with antitumor effect against hematological malignancies, thus representing a promising immunotherapy strategy. To ensure in vivo antitumor activity it is mandatory to maximize the percentage of CD3(+) 56(+) effector cells, which is highly variable depending on the starting sample and the harvesting day. Based on cytofluorimetric data, we have retrospectively applied multivariate statistical data analysis (MVDA) to 30 expansions building mathematical models able to predict the expansion fate and the optimal CIK harvesting day.
  
  
  METHODS
  Cell phenotype was monitored during culture; multivariate batch statistical process control was applied to monitor cell expansion and orthogonal projections to latent structures to predict CIK percentage.
  
  
  RESULTS
  Ten expansions had CD3(+) CD56(+) cells ≥ 40% (good batches) and 20 had CD3(+) CD56(+) cells ≤ 40%. In 36.7%, CD3(+) CD56(+) cells reached the highest concentration at day 17 and the others at day 21. We built a highly predictive regression model for estimating CD3(+) CD56(+) cells during culture. Three variables resulted highly informative: NK % at day 0, cytotoxic T-lymphocytes % (CTLs, CD3(+) CD8(+) ) at day 4, and CIK % at day 7. "Good batches" are characterized by a high percentage of CTLs and CD3(+) CD56(+) cells at day 4 and day 7, respectively.
  
  
  CONCLUSIONS
  By applying MVDA it is possible to optimize CIK expansion, deciding the optimal cell harvesting day. A predictive role for CTL and CIK was evidenced.
authors.affiliation: Advanced Cellular Therapy Laboratory, Department of Cell Therapy and Hematology, San Bortolo Hospital, Vicenza, 36100, Italy.
authors.forename: Cristina
authors.initials: C
authors.lastname: Zanon
authors.forename: Matteo
authors.initials: M
authors.lastname: Stocchero
authors.forename: Elena
authors.initials: E
authors.lastname: Albiero
authors.forename: Silvia
authors.initials: S
authors.lastname: Castegnaro
authors.forename: Katia
authors.initials: K
authors.lastname: Chieregato
authors.forename: Domenico
authors.initials: D
authors.lastname: Madeo
authors.forename: Francesco
authors.initials: F
authors.lastname: Rodeghiero
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Astori
mesh_terms: D018929:Cell Culture Techniques; D002478:Cells, Cultured; D055612:Cytokine-Induced Killer Cells / Q000166:cytology*; D006801:Humans; D015999:Multivariate Analysis; D010641:Phenotype
keywords: adoptive immunotherapy; cellular therapy; cytokine-induced killer cells; ex vivo expansion; multivariate statistical data analysis