title: Silencing of the glucocorticoid-induced leucine zipper improves the immunogenicity of clinical-grade dendritic cells.
abstract: BACKGROUND
  The maturation cocktail composed of interleukin (IL)-6, IL-1β, tumor necrosis factor-α and prostaglandin E2 is considered the "gold standard" for inducing the maturation of dendritic cells (DCs) for use in cancer immunotherapy. Nevertheless, although this maturation cocktail induces increased expression of several activation markers, such as CD83, the co-stimulation molecules CD80, CD86 and CD40 and the chemokine receptor involved in DC homing in lymph nodes CCR7, the DC immune stimulatory function in vivo contrasts with this mature phenotype, and good clinical outcomes in patients with cancer treated with DC-based vaccines remain rare.
  
  
  METHODS
  Phenotypic characterization of the immunosuppressive status of DCs differentiated from peripheral blood mononuclear cells of healthy volunteers and matured with the "gold standard" cocktail was performed. Glucocorticoid-induced leucine zipper (GILZ) targeting small interfering RNA (siRNA) was electroporated into DCs after maturation to increase their immunogenicity.
  
  
  RESULTS
  The mature phenotype of DCs treated for 48 h with this cocktail was associated with the expression of several immunosuppressive regulators, including programmed cell death 1 ligand 1 (PD-L1), IL-10 and GILZ. Electroporation is a very efficient and safe way to deliver siRNA into DCs (80% of DCs receive at least one molecule of siRNA). Silencing GILZ in clinical-grade DCs by siRNA leads to a decrease of the PD-L1 expression associated with an increase in their IL-12 secretion and T-cell induction capability.
  
  
  CONCLUSIONS
  GILZ silencing is a promising approach to achieving complete clinical-grade DC maturation and avoiding the immunosuppressive effects of the maturation cocktail on DCs intended for clinical use.
authors: Center for Cancer Immune Therapy (CCIT), University Hospital Herlev, Copenhagen, Denmark. dominique.cathelin@upmc.fr
authors: Dominique
authors: D
authors: Cathelin
authors: Özcan
authors: Ö
authors: Met
authors: Inge Marie
authors: IM
authors: Svane
mesh_terms: D002454:Cell Differentiation / Q000187:drug effects* / Q000276:immunology; D003713:Dendritic Cells / Q000166:cytology* / Q000378:metabolism; D015232:Dinoprostone / Q000008:administration & dosage; D018507:Gene Expression Regulation, Developmental / Q000187:drug effects; D005938:Glucocorticoids / Q000235:genetics* / Q000378:metabolism; D053583:Interleukin-1beta / Q000008:administration & dosage; D015850:Interleukin-6 / Q000008:administration & dosage; D016350:Leucine Zippers / Q000235:genetics* / Q000276:immunology; D007963:Leukocytes, Mononuclear / Q000166:cytology / Q000378:metabolism; D034741:RNA, Small Interfering / Q000235:genetics; D013601:T-Lymphocytes / Q000166:cytology / Q000187:drug effects / Q000276:immunology; D014409:Tumor Necrosis Factor-alpha / Q000008:administration & dosage
chemical_list: D005938:Glucocorticoids; D053583:Interleukin-1beta; D015850:Interleukin-6; D034741:RNA, Small Interfering; D014409:Tumor Necrosis Factor-alpha; D015232:Dinoprostone