Identification of novel myeloma-specific XBP1 peptides able to generate cytotoxic T lymphocytes: a potential therapeutic application in multiple myeloma

Leukemia. 2011 Oct;25(10):1610-9. doi: 10.1038/leu.2011.120. Epub 2011 Jun 10.


The purpose of these studies was to identify human leukocyte antigen (HLA)-A2(+) immunogenic peptides derived from XBP1 antigens to induce a multiple myeloma (MM)-specific immune response. Six native peptides from non-spliced XBP1 antigen and three native peptides from spliced XBP1 antigen were selected and evaluated for their HLA-A2 specificity. Among them, XBP1(184-192), XBP1 SP(196-204) and XBP1 SP(367-375) peptides showed the highest level of binding affinity, but not stability to HLA-A2 molecules. Novel heteroclitic XBP1 peptides, YISPWILAV or YLFPQLISV, demonstrated a significant improvement in HLA-A2 stability from their native XBP1(184-192) or XBP1 SP(367-375) peptide, respectively. Cytotoxic T lymphocytes generated by repeated stimulation of CD3(+) T cells with each HLA-A2-specific heteroclitic peptide showed an increased percentage of CD8(+) (cytotoxic) and CD69(+)/CD45RO(+) (activated memory) T cells and a lower percentage of CD4(+) (helper) and CD45RA(+)/CCR7(+) (naïve) T cells, which were distinct from the control T cells. Functionally, the cytotoxic T lymphocytes (CTL) demonstrated MM-specific and HLA-A2-restricted proliferation, interferon-γ secretion and cytotoxic activity in response to MM cell lines and importantly, cytotoxicity against primary MM cells. These data demonstrate the distinct immunogenic characteristics of unique heteroclitic XBP1 peptides, which induce MM-specific CTLs and highlights their potential application for immunotherapy to treat the patients with MM or its pre-malignant condition.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Amino Acid Sequence
  • Cell Line, Tumor
  • Cell Proliferation
  • DNA-Binding Proteins / chemistry
  • DNA-Binding Proteins / metabolism*
  • Enzyme-Linked Immunosorbent Assay
  • Humans
  • Multiple Myeloma / metabolism*
  • Multiple Myeloma / therapy
  • Peptide Fragments / immunology
  • Peptide Fragments / metabolism*
  • Peptide Fragments / therapeutic use
  • Regulatory Factor X Transcription Factors
  • T-Lymphocytes, Cytotoxic / cytology
  • T-Lymphocytes, Cytotoxic / immunology*
  • Transcription Factors / chemistry
  • Transcription Factors / metabolism*
  • X-Box Binding Protein 1


  • DNA-Binding Proteins
  • Peptide Fragments
  • Regulatory Factor X Transcription Factors
  • Transcription Factors
  • X-Box Binding Protein 1
  • XBP1 protein, human