title: Incubation of antigen-sensitized T lymphocytes activated with bryostatin 1 + ionomycin in IL-7 + IL-15 increases yield of cells capable of inducing regression of melanoma metastases compared to culture in IL-2.
abstract: Regression of established tumors can be induced by adoptive immunotherapy (AIT) with tumor draining lymph node (DLN) lymphocytes activated with bryostatin and ionomycin (B/I). We hypothesized that B/I-activated T cells cultured in IL-7 + IL-15 might proliferate and survive in culture better than cells cultured in IL-2, and that these cells would have equal or greater anti-tumor activity in vivo. Tumor antigen-sensitized DLN lymphocytes from either wild-type or T cell receptor transgenic mice were harvested, activated with B/I, and expanded in culture with either IL-2, IL-7 + IL-15 or a regimen of alternating cytokines. Cell yields, proliferation, apoptosis, phenotypes, and in vitro responses to tumor antigen were compared for cells grown in different cytokines. These T cells were also tested for anti-tumor activity against melanoma lung metastases established by prior i.v. injection of B16 melanoma cells. IL-7 + IL-15 or alternating cytokines resulted in much faster and prolonged proliferation and much less apoptosis of B/I-activated T cells than culturing the same cells in IL-2. This resulted in approximately tenfold greater yields of viable cells. Culture in IL-7 + IL-15 yielded higher proportions of CD8+ T cells and a higher proportion of cells with a central memory phenotype. Despite this, T cells grown in IL-7 + IL-15 had higher IFN-gamma release responses to tumor antigen than cells grown in IL-2. Adoptive transfer of B/I-activated T cells grown in IL-7 + IL-15 or the alternating regimen had equal or greater efficacy on a "per-cell" basis against melanoma metastases. Activation of tumor antigen-sensitized T cells with B/I and culture in IL-7 + IL-15 is a promising modification of standard regimens for production of T cells for use in adoptive immunotherapy of cancer.
authors.affiliation: Department of Physiology and Biophysics, Virginia Commonwealth University's Medical College of Virginia, Richmond, VA, USA. hanhkle@gmail.com
authors.forename: Hanh K
authors.initials: HK
authors.lastname: Le
authors.forename: Laura
authors.initials: L
authors.lastname: Graham
authors.forename: Catriona H T
authors.initials: CH
authors.lastname: Miller
authors.forename: Maciej
authors.initials: M
authors.lastname: Kmieciak
authors.forename: Masoud H
authors.initials: MH
authors.lastname: Manjili
authors.forename: Harry Douglas
authors.initials: HD
authors.lastname: Bear
mesh_terms: D000276:Adjuvants, Immunologic / Q000494:pharmacology; D000818:Animals; D017209:Apoptosis; D054713:Bryostatins / Q000494:pharmacology*; D049109:Cell Proliferation; D005434:Flow Cytometry; D016219:Immunotherapy, Adoptive; D007371:Interferon-gamma / Q000378:metabolism; D019409:Interleukin-15 / Q000494:pharmacology; D007376:Interleukin-2 / Q000494:pharmacology; D015851:Interleukin-7 / Q000494:pharmacology; D007378:Interleukins / Q000494:pharmacology*; D015759:Ionomycin / Q000494:pharmacology*; D008175:Lung Neoplasms / Q000276:immunology / Q000556:secondary / Q000628:therapy*; D008198:Lymph Nodes / Q000166:cytology; D008213:Lymphocyte Activation / Q000187:drug effects; D008546:Melanoma, Experimental / Q000276:immunology / Q000473:pathology / Q000628:therapy*; D051379:Mice; D008807:Mice, Inbred BALB C; D008810:Mice, Inbred C57BL; D008822:Mice, Transgenic; D010641:Phenotype; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013601:T-Lymphocytes / Q000276:immunology*; D014407:Tumor Cells, Cultured
chemical_list: D000276:Adjuvants, Immunologic; D054713:Bryostatins; D019409:Interleukin-15; D007376:Interleukin-2; D015851:Interleukin-7; D007378:Interleukins; D012333:RNA, Messenger; C046785:bryostatin 1; D015759:Ionomycin; D007371:Interferon-gamma