Direct antigen presentation and gap junction mediated cross-presentation during apoptosis.

نویسندگان

  • Baoxu Pang
  • Joost Neijssen
  • Xiaohang Qiao
  • Lennert Janssen
  • Hans Janssen
  • Christoph Lippuner
  • Jacques Neefjes
چکیده

MHC class I molecules present peptides from endogenous proteins. Ags can also be presented when derived from extracellular sources in the form of apoptotic bodies. Cross-presentation of such Ags by dendritic cells is required for proper CTL responses. The fate of Ags in cells initiated for apoptosis is unclear as is the mechanism of apoptosis-derived Ag transfer into dendritic cells. Here we show that novel Ags can be generated by caspases and be presented by MHC class I molecules of apoptotic cells. Since gap junctions function until apoptotic cells remodel to form apoptotic bodies, transfer and cross-presentation of apoptotic peptides by neighboring and dendritic cells occurs. We thus define a novel phase in classical Ag presentation and cross-presentation by MHC class I molecules: presentation of Ags created by caspase activities in cells in apoptosis.

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عنوان ژورنال:
  • Journal of immunology

دوره 183 2  شماره 

صفحات  -

تاریخ انتشار 2009