Tapasin decreases immune responsiveness to a model tumor antigen

Heth R. Turnquist, Karl G. Kohlgraf, Mary M. McIlhaney, R Lee Mosley, Michael A Hollingsworth, Joyce C Solheim

Research output: Contribution to journalArticle

8 Scopus citations


The T-cell response against cancer is dependent on the cell surface presentation of tumor-associated or tumor-specific peptides by major histocompatibility complex (MHC) class I molecules. We found that tapasin, a chaperone protein that normally assists in the assembly of MHC class I molecules, is undetectable in an unstimulated pancreatic tumor cell line, Panc02, and only very weakly expressed after γ-interferon stimulation. Transfection of tapasin into the Panc02 cells did not quantitatively increase MHC class I surface expression or detectably affect MHC class I association with peptide and β2-microglubulin (β2m). However, we found that transfected tapasin downregulated immune reactivity against a model tumor antigen, MUC1. Although tapasin has been previously shown by others to increase immune recognition of particular antigens, our results suggest that tapasin has a negative impact on the presentation of an immunodominant epitope from a specific model tumor antigen.

Original languageEnglish (US)
Pages (from-to)462-470
Number of pages9
JournalJournal of Clinical Immunology
Issue number4
Publication statusPublished - Jul 1 2004



  • Antigen presentation
  • MHC
  • Pancreatic cancer
  • Tapasin
  • Tumor antigen

ASJC Scopus subject areas

  • Immunology and Allergy
  • Immunology

Cite this