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Presentation of exogenous antigens on major histocompatibility complex (MHC) class I and MHC class II molecules is differentially regulated during dendritic cell maturation.

Delamarre L, Holcombe H, Mellman I - J. Exp. Med. (2003)

Bottom Line: Unlike MHC II, these events do not involve a marked redistribution of preexisting MHC I molecules from intracellular compartments to the DC surface.In contrast, formation of peptide-MHC I complexes from endogenous cytosolic antigens occurs even in unstimulated, immature DCs.Thus, the MHC I and MHC II pathways of antigen presentation are differentially regulated during DC maturation.

View Article: PubMed Central - PubMed

Affiliation: Department of Cell Biology and Section of Immunobiology, Ludwig Institute for Cancer Research, Yale University School of Medicine, New Haven, CT 06520-8002, USA.

ABSTRACT
During maturation, dendritic cells (DCs) regulate their capacity to process and present major histocompatibility complex (MHC) II-restricted antigens. Here we show that presentation of exogenous antigens by MHC I is also subject to developmental control, but in a fashion strikingly distinct from MHC II. Immature mouse bone marrow-derived DCs internalize soluble ovalbumin and sequester the antigen intracellularly until they receive an appropriate signal that induces cross presentation. At that time, peptides are generated in a proteasome-dependent fashion and used to form peptide-MHC I complexes that appear at the plasma membrane. Unlike MHC II, these events do not involve a marked redistribution of preexisting MHC I molecules from intracellular compartments to the DC surface. Moreover, out of nine stimuli well known to induce the phenotypic maturation of DCs and to promote MHC II presentation, only two (CD40 ligation, disruption of cell-cell contacts) activated cross presentation on MHC I. In contrast, formation of peptide-MHC I complexes from endogenous cytosolic antigens occurs even in unstimulated, immature DCs. Thus, the MHC I and MHC II pathways of antigen presentation are differentially regulated during DC maturation.

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Not all maturation stimuli induce cross presentation. (A) Immature B6D2F1 DCs were pulsed with OVA (1mg/ml) or BSA as a control for 2 h, washed, activated by addition of the indicated stimuli, and chased for 7 h before fixation and culture with OT.1 T cells. T cell responses were monitored at 24 h by measuring IL-2 release. (B) Maturation was monitored at the level of cell surface MHC II (x-axis) and CD86 (y-axis) by flow cytometry on the CD11c-positive population of unpulsed day 4 cultures activated with the indicated stimuli for 7 h. (C) The procedure was the same as described in panel A except that the DC cultures were chased for the indicated periods after stimulation with anti-CD40 Ab or bacteria. As a control, OVA-pulsed DCs stimulated for 7 h by addition of LPS and by cluster disruption were used. Results are representative of three experiments. (*) indicates below level of detection.
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fig5: Not all maturation stimuli induce cross presentation. (A) Immature B6D2F1 DCs were pulsed with OVA (1mg/ml) or BSA as a control for 2 h, washed, activated by addition of the indicated stimuli, and chased for 7 h before fixation and culture with OT.1 T cells. T cell responses were monitored at 24 h by measuring IL-2 release. (B) Maturation was monitored at the level of cell surface MHC II (x-axis) and CD86 (y-axis) by flow cytometry on the CD11c-positive population of unpulsed day 4 cultures activated with the indicated stimuli for 7 h. (C) The procedure was the same as described in panel A except that the DC cultures were chased for the indicated periods after stimulation with anti-CD40 Ab or bacteria. As a control, OVA-pulsed DCs stimulated for 7 h by addition of LPS and by cluster disruption were used. Results are representative of three experiments. (*) indicates below level of detection.

Mentions: To examine this suggestion in greater detail, we tested various stimuli known to induce DC maturation and MHC II–restricted presentation for their capacity to promote cross presentation. OVA-pulsed DCs were cultured for 7 h in the presence of each stimulus. Relative to “LPS and cluster disruption” treatment, none of the stimuli tested were able to promote cross presentation (Fig. 5 A). This was despite the fact that all triggered phenotypic DC maturation as indicated by increased expression of MHC II and CD86 (Fig. 5 B) as well as MHC II presentation (see below).


Presentation of exogenous antigens on major histocompatibility complex (MHC) class I and MHC class II molecules is differentially regulated during dendritic cell maturation.

Delamarre L, Holcombe H, Mellman I - J. Exp. Med. (2003)

Not all maturation stimuli induce cross presentation. (A) Immature B6D2F1 DCs were pulsed with OVA (1mg/ml) or BSA as a control for 2 h, washed, activated by addition of the indicated stimuli, and chased for 7 h before fixation and culture with OT.1 T cells. T cell responses were monitored at 24 h by measuring IL-2 release. (B) Maturation was monitored at the level of cell surface MHC II (x-axis) and CD86 (y-axis) by flow cytometry on the CD11c-positive population of unpulsed day 4 cultures activated with the indicated stimuli for 7 h. (C) The procedure was the same as described in panel A except that the DC cultures were chased for the indicated periods after stimulation with anti-CD40 Ab or bacteria. As a control, OVA-pulsed DCs stimulated for 7 h by addition of LPS and by cluster disruption were used. Results are representative of three experiments. (*) indicates below level of detection.
© Copyright Policy
Related In: Results  -  Collection

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fig5: Not all maturation stimuli induce cross presentation. (A) Immature B6D2F1 DCs were pulsed with OVA (1mg/ml) or BSA as a control for 2 h, washed, activated by addition of the indicated stimuli, and chased for 7 h before fixation and culture with OT.1 T cells. T cell responses were monitored at 24 h by measuring IL-2 release. (B) Maturation was monitored at the level of cell surface MHC II (x-axis) and CD86 (y-axis) by flow cytometry on the CD11c-positive population of unpulsed day 4 cultures activated with the indicated stimuli for 7 h. (C) The procedure was the same as described in panel A except that the DC cultures were chased for the indicated periods after stimulation with anti-CD40 Ab or bacteria. As a control, OVA-pulsed DCs stimulated for 7 h by addition of LPS and by cluster disruption were used. Results are representative of three experiments. (*) indicates below level of detection.
Mentions: To examine this suggestion in greater detail, we tested various stimuli known to induce DC maturation and MHC II–restricted presentation for their capacity to promote cross presentation. OVA-pulsed DCs were cultured for 7 h in the presence of each stimulus. Relative to “LPS and cluster disruption” treatment, none of the stimuli tested were able to promote cross presentation (Fig. 5 A). This was despite the fact that all triggered phenotypic DC maturation as indicated by increased expression of MHC II and CD86 (Fig. 5 B) as well as MHC II presentation (see below).

Bottom Line: Unlike MHC II, these events do not involve a marked redistribution of preexisting MHC I molecules from intracellular compartments to the DC surface.In contrast, formation of peptide-MHC I complexes from endogenous cytosolic antigens occurs even in unstimulated, immature DCs.Thus, the MHC I and MHC II pathways of antigen presentation are differentially regulated during DC maturation.

View Article: PubMed Central - PubMed

Affiliation: Department of Cell Biology and Section of Immunobiology, Ludwig Institute for Cancer Research, Yale University School of Medicine, New Haven, CT 06520-8002, USA.

ABSTRACT
During maturation, dendritic cells (DCs) regulate their capacity to process and present major histocompatibility complex (MHC) II-restricted antigens. Here we show that presentation of exogenous antigens by MHC I is also subject to developmental control, but in a fashion strikingly distinct from MHC II. Immature mouse bone marrow-derived DCs internalize soluble ovalbumin and sequester the antigen intracellularly until they receive an appropriate signal that induces cross presentation. At that time, peptides are generated in a proteasome-dependent fashion and used to form peptide-MHC I complexes that appear at the plasma membrane. Unlike MHC II, these events do not involve a marked redistribution of preexisting MHC I molecules from intracellular compartments to the DC surface. Moreover, out of nine stimuli well known to induce the phenotypic maturation of DCs and to promote MHC II presentation, only two (CD40 ligation, disruption of cell-cell contacts) activated cross presentation on MHC I. In contrast, formation of peptide-MHC I complexes from endogenous cytosolic antigens occurs even in unstimulated, immature DCs. Thus, the MHC I and MHC II pathways of antigen presentation are differentially regulated during DC maturation.

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