title: Apoptosis-induced inhibition of CD1d-mediated antigen presentation: different roles for caspases and signal transduction pathways.
abstract: The stimulation of programmed cell death can either enhance or inhibit antigen presentation by classic major histocompatibility complex molecules. In the current study, we report that the induction of apoptosis by topoisomerase I inhibition or elevation of intracellular ceramide levels substantially impairs CD1d-mediated antigen presentation. In the former case, such a reduction occurred via the regulation of both the p38 mitogen-activated protein kinases and protein kinase C delta signal transduction pathways as well as the caspase cascade, whereas the latter was p38-(but not caspase)-dependent. Confocal microscopic analysis showed an altered intracellular distribution of CD1d following the inhibition topoisomerase I or by an increase in intracellular ceramide levels, that was prevented by p38 and caspase inhibitors. Thus, the induction of apoptosis in antigen presenting cells severely compromises CD1d-mediated antigen presentation by multiple mechanisms.
authors.affiliation: Department of Microbiology and Immunology, Indiana University School of Medicine, Indianapolis, IN 46202-5181, USA.
authors.forename: Masood A
authors.initials: MA
authors.lastname: Khan
authors.forename: Venkataraman
authors.initials: V
authors.lastname: Sriram
authors.forename: Gourapura J
authors.initials: GJ
authors.lastname: Renukaradhya
authors.forename: Wenjun
authors.initials: W
authors.lastname: Du
authors.forename: Jacquelyn
authors.initials: J
authors.lastname: Gervay-Hague
authors.forename: Randy R
authors.initials: RR
authors.lastname: Brutkiewicz
mesh_terms: D000818:Animals; D017951:Antigen Presentation / Q000187:drug effects / Q000276:immunology*; D018949:Antigens, CD1 / Q000276:immunology*; D055610:Antigens, CD1d; D017209:Apoptosis / Q000276:immunology*; D002166:Camptothecin / Q000494:pharmacology; D020169:Caspases / Q000276:immunology*; D002478:Cells, Cultured; D002518:Ceramides / Q000494:pharmacology; D018920:Coculture Techniques; D005260:Female; D005699:Galactosylceramides / Q000494:pharmacology; D008614:Meperidine / Q000031:analogs & derivatives / Q000494:pharmacology; D051379:Mice; D008810:Mice, Inbred C57BL; D051745:Protein Kinase C-delta / Q000276:immunology; D015398:Signal Transduction / Q000276:immunology*; D048051:p38 Mitogen-Activated Protein Kinases / Q000276:immunology
chemical_list: D018949:Antigens, CD1; D055610:Antigens, CD1d; D002518:Ceramides; D005699:Galactosylceramides; C493154:alpha-galactosylceramide; C026733:4-propionyloxy-4-phenyl-N-methylpiperidine; D008614:Meperidine; C497259:Prkcd protein, mouse; D051745:Protein Kinase C-delta; D048051:p38 Mitogen-Activated Protein Kinases; D020169:Caspases; D002166:Camptothecin