Expansion of T Cells with Interleukin-21 for Adoptive Immunotherapy of Murine Mammary Carcinoma.
We previously demonstrated that culturing antigen-sensitized draining lymph node (DLN) lymphocytes from BALB/c mice in interleukin (IL)-7/15 after activation with bryostatin/ionomycin (B/I) is superior to culture in IL-2 for expansion, differentiation to cluster of differentiation (CD)8+ cells and anti-tumor activity. We sought to determine whether the substitution or addition of IL-21 to culture had a similar effect. DLN lymphocytes were antigen-sensitized with 4T1 mammary carcinoma 10 days prior to harvest, activated with B/I, and expanded in culture for 7 days with either IL-2, IL-21, IL-2/21, IL-7/15, or IL-7/15/21. Cellular expansion, phenotype, interferon (IFN)-γ responses, and in vivo anti-tumor activity were compared. We found that T cells grown in IL7/15/21 demonstrated significantly greater lymphocyte expansion than IL-2, IL-21, IL-2/21, and IL-7/15 (38.4-fold vs. 5.5, 6.6, 9.5, and 23.9-fold, respectively). Of these expanded cells, IL-7/15/21 significantly expanded the greatest percentage of CD8+ cells (67.1% vs. 22.2%, 47.2%, 47.4%, and 55.3%, respectively), and the greatest number of T central memory cells (TCM) compared to IL-2, IL-21 and IL-2/21 (45.8% vs. 11.1%, 7.7%, and 12.1%, respectively). IL-21 and IL-2/21-expanded T cells preferentially differentiated into T naïve cells (TN) vs. those expanded in IL-2, IL-7/15 and IL-7/15/21 (27.6% and 23.2% vs. 1.7%, 4.5%, and 10.4%, respectively), and demonstrated the highest IFN-γ levels in vitro. In vivo adoptive immunotherapy (AIT) experiments demonstrated anti-tumor efficacy was equally effective using IL-2, IL-21, IL-2/21, IL-7/15 and IL-7/15/21-cultured lymphocytes vs. control or cyclophosphamide alone, even at lower doses or with greater initial size of tumor prior to treatment.
Department of Surgery, Virginia Commonwealth University Health System, Richmond, VA 23298, USA. ckzoon@comcast.net.
Christine K
CK
Zoon
Department of Biostatistics, Virginia Commonwealth University School of Medicine, Richmond, VA 23298, USA. wwan@vcu.edu.
Wen
W
Wan
Division of Surgical Oncology, Virginia Commonwealth University Massey Cancer Center, Richmond, VA 23298, USA. LGraham2@MCVH-VCU.EDU.
Laura
L
Graham
Division of Surgical Oncology, Virginia Commonwealth University Massey Cancer Center, Richmond, VA 23298, USA. hdbear@vcu.edu.
Harry D
HD
Bear
D000818:Animals; D015415:Biomarkers; D004195:Disease Models, Animal; D005260:Female; D016130:Immunophenotyping; D016219:Immunotherapy, Adoptive / Q000379:methods; D007378:Interleukins / Q000494:pharmacology*; D008213:Lymphocyte Activation; D008325:Mammary Neoplasms, Experimental / Q000276:immunology* / Q000378:metabolism / Q000473:pathology; D051379:Mice; D010641:Phenotype; D061251:Primary Cell Culture; D016176:T-Lymphocyte Subsets / Q000187:drug effects* / Q000276:immunology* / Q000378:metabolism; D047368:Tumor Burden / Q000276:immunology; D000098546:Interleukin-21
D015415:Biomarkers; D007378:Interleukins; D000098546:Interleukin-21
IL-21; T lymphocytes; adoptive immunotherapy; mammary carcinoma