title: Survivin-specific CD4+ T cells are decreased in patients with survivin-positive myeloma.
abstract: BACKGROUND
  Survivin is a small protein inhibitor of apoptosis and a tumor associated antigen. Survivin expression in multiple myeloma is associated with poor prognosis, disease progression, and drug resistance. The CD4+ response against survivin remains uncharacterized.
  
  
  METHODS
  In order to better understand the anti-tumor immune response to survivin, and optimize vaccination strategies, we characterized the spontaneous CD4+CD25- T cell response against survivin in healthy donors and myeloma patients using survivin derived peptide pools.
  
  
  RESULTS
  Healthy donors and myeloma patients' CD4+CD25- T cells exhibited a proliferative and IFN-gamma response against survivin peptides loaded onto autologous dendritic cells. We employed limiting dilution analysis to quantify the precursor frequency of survivin reactive CD4+CD25- T cells. Multiple myeloma patients (range 0% to 2.2x10(-3)%, n=12) had fewer survivin reactive CD4+CD25- T cells than healthy blood donors (range 1.1x10(-3) to 8.4x10(-3)%, n=10), p = 0.021. The survivin reactive CD4+CD25- T cell precursor frequency was inversely associated with tumor survivin mRNA expression (p = 0.0028, r = -1.0, n = 6), and survivin tumor protein expression by IHC (p = 0.0295, r = -0.67, n = 10). A full length mutant survivin protein-pulsed dendritic cell vaccine expanded survivin reactive CD4+CD25- T cells after 12 days of in vitro culture (range 0-540x,median = 42x), and expansion was achieved even in patients with low baseline survivin reactive CD4+ precursors.
  
  
  CONCLUSIONS
  We have, for the first time, quantified the circulating CD4+CD25- precursor frequency against survivin and demonstrated this is lower in myeloma patients than healthy donors. The number of survivin reactive CD4+CD25- T cells is inversely associated with tumor survivin expression suggesting suppression of survivin responsive CD4+CD25- T cells. Further exploration of a full length mutant survivin protein vaccine which expands survivin reactive CD4+ cells independent of the survivin reactive precursor frequency is warranted.
authors.affiliation: Moffitt Cancer Center, Department of Blood and Marrow Transplantation, Tampa, USA.
authors.forename: Frederick L
authors.identifier: 0000-0001-9063-6691
authors.initials: FL
authors.lastname: Locke
authors.affiliation: Moffitt Cancer Center, Department of Blood and Marrow Transplantation, Tampa, USA.
authors.forename: Meghan
authors.initials: M
authors.lastname: Menges
authors.affiliation: Moffitt Cancer Center, Department of Blood and Marrow Transplantation, Tampa, USA.
authors.forename: Anandharaman
authors.initials: A
authors.lastname: Veerapathran
authors.affiliation: Moffitt Cancer Center, Department of Pathology, Tampa, USA.
authors.forename: Domenico
authors.initials: D
authors.lastname: Coppola
authors.affiliation: The Wistar Institute, Tumor Microenvironment and Metastasis Program, Philadelphia, USA.
authors.forename: Dmitry
authors.initials: D
authors.lastname: Gabrilovich
authors.affiliation: Moffitt Cancer Center, Department of Blood and Marrow Transplantation, Tampa, USA.
authors.forename: Claudio
authors.initials: C
authors.lastname: Anasetti