Natural-killer cell amplification for adoptive leukemia relapse immunotherapy: Comparison of three cytokines, IL-2, IL-15, or IL-7 and impact on NKG2D, KIR2DL1, and KIR2DL2 expression
Received 8 July 2009; received in revised form 18 December 2009; accepted 9 February 2010. published online 22 February 2010.
Objective
Natural killer (NK) cells are a lymphocyte subset that, in a hematopoietic stem cell transplantation setting, mediates a graft-vs-leukemia effect without any graft-vs-host disease. We aimed to evaluate an isolation method that can be used with Good Manufacturing Practices−grade reagents and to compare three cytokines for expansion in order to design future clinical protocols based on donor NK-cell infusions to cure relapse after allograft.
Materials and Methods
NK cells were enriched using a CD3/CD19 depletion method and expanded for 13 days in the presence of 2, 10, and 50 ng/mL interleukin (IL)-2, IL-15, or IL-7. NK-cell cytotoxicity was evaluated after isolation and culture. Expression of NKG2D, KIR2DL2, and KIR2DL1 was monitored during expansion.
Results
Highly T- and B-cell−depleted NK cells were obtained and enriched 2.6-fold. The optimal cytokine concentration for expansion was 10 ng/mL for IL-2 or 50 ng/mL for IL-15. NK-cell cytotoxicity was significantly improved after an overnight incubation with 10 or 50 ng/mL IL-2 or with 2, 10, or 50 ng/mL IL-15, and after 13 days with 50 ng/mL IL-15. The use of a combination of IL-2 and IL-15 showed no additional benefit and negative results were obtained with IL-7. The three NK cell receptors were significantly upregulated after culture, mainly with IL-2 or IL-15.
Conclusion
In our study, 10 ng/mL IL-2 or 50 ng/mL IL-15 were the optimal concentrations for expansion and were equivalent in significantly enhancing cytotoxicity and modifying NK-cell receptor expression patterns.
aUnité de Thérapie Cellulaire et Tissus, CHU Nancy, Nancy, France
bNancy Université, UHP-UMR CNRS 7561, Faculté de Médecine, Vandoeuvre-lès-Nancy, Nancy, France
cService d'Hématologie Biologique, CHU de Nancy, Nancy, France
dService d'Histocompatibilité, CHU Nancy, Nancy, France
Offprint requests to: Véronique Decot, Ph.D., Cell Therapy and Tissue Unit, CHU Nancy, allée du Morvan, 54511 Vandoeuvre les Nancy, France
ABSTRACT