Constitutive macropinocytosis allows TAP-dependent major histocompatibility compex class I presentation of exogenous soluble antigen by bone marrow-derived dendritic cells

Christopher C. Norbury, Benedict J. Chambers, Alan R. Prescott, Hans Gustaf Ljunggren, Colin Watts

Research output: Contribution to journalArticle

283 Scopus citations

Abstract

Dendritic cells expanded from mouse bone marrow (BMDC) with granulocyte/macrophage-colony-stimulating factor have potent T cell-stimulatory properties both in vitro and in vivo. This has been well documented for major histocompatibility complex (MHC) class II-restricted responses, and more recently using peptide-loaded and protein-pulsed DC for CD8 responses following adoptive transfer in mice. An unresolved question concerns the capacity of BMDC to present exogenous antigen on MHC class I molecules, an unconventional mode of MHC class I loading for which there is now considerable evidence, particularly in macrophages. Here, we show that BMDC exhibit high levels of macropinocytosis driven by constitutive membrane ruffling activity. Up to one-third of actively ruffling and macropinocytosing BMDC transferred pinocytosed horseradish peroxidase into the cytosol following a 15-min pulse, suggesting that they might be capable of presenting exogenous soluble antigen on MHC class I molecules. We show that BMDC presented exogenous ovalbumin to a T cell hybridoma more effectively, more rapidly, and at lower exogenous antigen concentrations than BM macrophages on a cell-for-cell basis. Presentation was TAP dependent, brefeldin A sensitive, and blocked by inhibitors of proteasomal processing, demonstrating use of the classical MHC class I pathway. Although effective presentation of exogenous antigen by BMDC occurred in the absence of agents which stimulate macropinocytosis, treatment with phorbol myristate acetate (PMA) enhanced both pinocytosis and MHC class I presentation by BMDC. Finally, PMA-stimulated BMDC exposed to exogenous ovalbumin in vitro were able to prime an antigen-specific cytotoxic T lymphocyte response following adoptive transfer in vivo.

Original languageEnglish (US)
Pages (from-to)280-288
Number of pages9
JournalEuropean Journal of Immunology
Volume27
Issue number1
DOIs
StatePublished - Jan 1 1997

All Science Journal Classification (ASJC) codes

  • Immunology and Allergy
  • Immunology

Fingerprint Dive into the research topics of 'Constitutive macropinocytosis allows TAP-dependent major histocompatibility compex class I presentation of exogenous soluble antigen by bone marrow-derived dendritic cells'. Together they form a unique fingerprint.

  • Cite this