Corpse disposal after apoptosis

P Rovere-Querini1, I E Dumitriu

  • 1Clinical Immunology Unit, Cancer Immunotherapy & Gene Therapy Program, Istituto Scientifico Ospedale San Raffaele, via Olgettina 58, 20132 Milano, Italy. rovere.patrizia@hsr.it

The termination of the apoptotic program occurs in most cases via recognition and clearance by phagocytes. Engulfed cells do not simply disappear from the midst of living tissues. Constituents of the corpse indeed survive the intracellular processing and are recycled to the membrane of the phagocyte. The presentation of yielded antigens to T cells is a central event in the induction and the maintenance of peripheral tolerance. Conversely, errors in this pathway contribute to the pathogenesis of systemic and organ specific autoimmune diseases. Here we discuss the available information on the events that follow active engulfment of dying cells, with attention to the events involved in vitro and in vivo in apoptotic cell processing. The outcome of the processing is the cross-priming or the functional inactivation of T cells that specifically recognise antigens contained in the cell corpse.

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