Direct visualization of peptide/MHC complexes at the surface and in the intracellular compartments of cells infected in vivo by Leishmania major.
Protozoa and bacteria infect various types of phagocytic cells including macrophages, monocytes, dendritic cells and eosinophils. However, it is not clear which of these cells process and present microbial antigens in vivo and in which cellular compartments parasite peptides are loaded onto Major Hi...
Saved in:
| Main Authors: | , , , , , , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
Public Library of Science (PLoS)
2010-10-01
|
| Series: | PLoS Pathogens |
| Online Access: | https://journals.plos.org/plospathogens/article/file?id=10.1371/journal.ppat.1001154&type=printable |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
| _version_ | 1841527085429948416 |
|---|---|
| author | Eric Muraille Pierre Gounon Julie Cazareth Johan Hoebeke Christoph Lippuner Ana Davalos-Misslitz Toni Aebischer Sylviane Muller Nicolas Glaichenhaus Evelyne Mougneau |
| author_facet | Eric Muraille Pierre Gounon Julie Cazareth Johan Hoebeke Christoph Lippuner Ana Davalos-Misslitz Toni Aebischer Sylviane Muller Nicolas Glaichenhaus Evelyne Mougneau |
| author_sort | Eric Muraille |
| collection | DOAJ |
| description | Protozoa and bacteria infect various types of phagocytic cells including macrophages, monocytes, dendritic cells and eosinophils. However, it is not clear which of these cells process and present microbial antigens in vivo and in which cellular compartments parasite peptides are loaded onto Major Histocompatibility Complex molecules. To address these issues, we have infected susceptible BALB/c (H-2d) mice with a recombinant Leishmania major parasite expressing a fluorescent tracer. To directly visualize the antigen presenting cells that present parasite-derived peptides to CD4+ T cells, we have generated a monoclonal antibody that reacts to an antigenic peptide derived from the parasite LACK antigen bound to I-Ad Major Histocompatibility Complex class II molecule. Immunogold electron microscopic analysis of in vivo infected cells showed that intracellular I-Ad/LACK complexes were present in the membrane of amastigote-containing phagosomes in dendritic cells, eosinophils and macrophages/monocytes. In both dendritic cells and macrophages, these complexes were also present in smaller vesicles that did not contain amastigote. The presence of I-Ad/LACK complexes at the surface of dendritic cells, but neither on the plasma membrane of macrophages nor eosinophils was independently confirmed by flow cytometry and by incubating sorted phagocytes with highly sensitive LACK-specific hybridomas. Altogether, our results suggest that peptides derived from Leishmania proteins are loaded onto Major Histocompatibility Complex class II molecules in the phagosomes of infected phagocytes. Although these complexes are transported to the cell surface in dendritic cells, therefore allowing the stimulation of parasite-specific CD4+ T cells, this does not occur in other phagocytic cells. To our knowledge, this is the first study in which Major Histocompatibility Complex class II molecules bound to peptides derived from a parasite protein have been visualized within and at the surface of cells that were infected in vivo. |
| format | Article |
| id | doaj-art-3921aa75d83d46a3ac69c0849951094b |
| institution | Kabale University |
| issn | 1553-7366 1553-7374 |
| language | English |
| publishDate | 2010-10-01 |
| publisher | Public Library of Science (PLoS) |
| record_format | Article |
| series | PLoS Pathogens |
| spelling | doaj-art-3921aa75d83d46a3ac69c0849951094b2025-01-16T05:31:02ZengPublic Library of Science (PLoS)PLoS Pathogens1553-73661553-73742010-10-01610e100115410.1371/journal.ppat.1001154Direct visualization of peptide/MHC complexes at the surface and in the intracellular compartments of cells infected in vivo by Leishmania major.Eric MuraillePierre GounonJulie CazarethJohan HoebekeChristoph LippunerAna Davalos-MisslitzToni AebischerSylviane MullerNicolas GlaichenhausEvelyne MougneauProtozoa and bacteria infect various types of phagocytic cells including macrophages, monocytes, dendritic cells and eosinophils. However, it is not clear which of these cells process and present microbial antigens in vivo and in which cellular compartments parasite peptides are loaded onto Major Histocompatibility Complex molecules. To address these issues, we have infected susceptible BALB/c (H-2d) mice with a recombinant Leishmania major parasite expressing a fluorescent tracer. To directly visualize the antigen presenting cells that present parasite-derived peptides to CD4+ T cells, we have generated a monoclonal antibody that reacts to an antigenic peptide derived from the parasite LACK antigen bound to I-Ad Major Histocompatibility Complex class II molecule. Immunogold electron microscopic analysis of in vivo infected cells showed that intracellular I-Ad/LACK complexes were present in the membrane of amastigote-containing phagosomes in dendritic cells, eosinophils and macrophages/monocytes. In both dendritic cells and macrophages, these complexes were also present in smaller vesicles that did not contain amastigote. The presence of I-Ad/LACK complexes at the surface of dendritic cells, but neither on the plasma membrane of macrophages nor eosinophils was independently confirmed by flow cytometry and by incubating sorted phagocytes with highly sensitive LACK-specific hybridomas. Altogether, our results suggest that peptides derived from Leishmania proteins are loaded onto Major Histocompatibility Complex class II molecules in the phagosomes of infected phagocytes. Although these complexes are transported to the cell surface in dendritic cells, therefore allowing the stimulation of parasite-specific CD4+ T cells, this does not occur in other phagocytic cells. To our knowledge, this is the first study in which Major Histocompatibility Complex class II molecules bound to peptides derived from a parasite protein have been visualized within and at the surface of cells that were infected in vivo.https://journals.plos.org/plospathogens/article/file?id=10.1371/journal.ppat.1001154&type=printable |
| spellingShingle | Eric Muraille Pierre Gounon Julie Cazareth Johan Hoebeke Christoph Lippuner Ana Davalos-Misslitz Toni Aebischer Sylviane Muller Nicolas Glaichenhaus Evelyne Mougneau Direct visualization of peptide/MHC complexes at the surface and in the intracellular compartments of cells infected in vivo by Leishmania major. PLoS Pathogens |
| title | Direct visualization of peptide/MHC complexes at the surface and in the intracellular compartments of cells infected in vivo by Leishmania major. |
| title_full | Direct visualization of peptide/MHC complexes at the surface and in the intracellular compartments of cells infected in vivo by Leishmania major. |
| title_fullStr | Direct visualization of peptide/MHC complexes at the surface and in the intracellular compartments of cells infected in vivo by Leishmania major. |
| title_full_unstemmed | Direct visualization of peptide/MHC complexes at the surface and in the intracellular compartments of cells infected in vivo by Leishmania major. |
| title_short | Direct visualization of peptide/MHC complexes at the surface and in the intracellular compartments of cells infected in vivo by Leishmania major. |
| title_sort | direct visualization of peptide mhc complexes at the surface and in the intracellular compartments of cells infected in vivo by leishmania major |
| url | https://journals.plos.org/plospathogens/article/file?id=10.1371/journal.ppat.1001154&type=printable |
| work_keys_str_mv | AT ericmuraille directvisualizationofpeptidemhccomplexesatthesurfaceandintheintracellularcompartmentsofcellsinfectedinvivobyleishmaniamajor AT pierregounon directvisualizationofpeptidemhccomplexesatthesurfaceandintheintracellularcompartmentsofcellsinfectedinvivobyleishmaniamajor AT juliecazareth directvisualizationofpeptidemhccomplexesatthesurfaceandintheintracellularcompartmentsofcellsinfectedinvivobyleishmaniamajor AT johanhoebeke directvisualizationofpeptidemhccomplexesatthesurfaceandintheintracellularcompartmentsofcellsinfectedinvivobyleishmaniamajor AT christophlippuner directvisualizationofpeptidemhccomplexesatthesurfaceandintheintracellularcompartmentsofcellsinfectedinvivobyleishmaniamajor AT anadavalosmisslitz directvisualizationofpeptidemhccomplexesatthesurfaceandintheintracellularcompartmentsofcellsinfectedinvivobyleishmaniamajor AT toniaebischer directvisualizationofpeptidemhccomplexesatthesurfaceandintheintracellularcompartmentsofcellsinfectedinvivobyleishmaniamajor AT sylvianemuller directvisualizationofpeptidemhccomplexesatthesurfaceandintheintracellularcompartmentsofcellsinfectedinvivobyleishmaniamajor AT nicolasglaichenhaus directvisualizationofpeptidemhccomplexesatthesurfaceandintheintracellularcompartmentsofcellsinfectedinvivobyleishmaniamajor AT evelynemougneau directvisualizationofpeptidemhccomplexesatthesurfaceandintheintracellularcompartmentsofcellsinfectedinvivobyleishmaniamajor |