Harboring of particulate allergens within secretory compartments by mast cells following IgE/FcepsilonRI-lipid raft-mediated phagocytosis.
Although much is known regarding the exocytic responses of mast cells following allergen/IgE-mediated activation, little is currently known of the fate of the activating allergens, many of which are particles. We have found that IgE-bound particulate allergens were phagocytosed by activated mast cells in a lipid raft-dependent manner. The nascent allergen-containing phagosomes were found to transform into granule compartments by acquiring VAMP7 and serotonin and exhibited the capacity to empty their contents upon mast cell activation. When allergen-harboring mast cells were stimulated, the intracellular allergens were expelled intact and shown to activate adjacent mast cells. This capacity of mast cells to phagocytose and retain whole and antigenically intact allergens could potentially contribute to the course of inflammatory diseases such as asthma.
Shin
Jeoung-Sook
JS
Department of Pathology, Duke University Medical School, Durham, NC 27710, USA.
Shelburne
Christopher P
CP
Jin
Cong
C
LeFurgey
E Ann
EA
Abraham
Soman N
SN
D000485:Allergens / Q000276:immunology / Q000378:metabolism* / Q000648:ultrastructure; D000818:Animals; D007073:Immunoglobulin E / Q000032:analysis / Q000378:metabolism*; D008407:Mast Cells / Q000276:immunology* / Q000648:ultrastructure; D021962:Membrane Microdomains / Q000737:chemistry / Q000276:immunology*; D051379:Mice; D008810:Mice, Inbred C57BL; D010587:Phagocytosis; D010588:Phagosomes / Q000737:chemistry / Q000276:immunology; D011058:Pollen / Q000276:immunology / Q000378:metabolism* / Q000648:ultrastructure; D050683:R-SNARE Proteins / Q000032:analysis / Q000235:genetics / Q000378:metabolism; D017455:Receptors, IgE / Q000032:analysis / Q000378:metabolism*; D012701:Serotonin / Q000032:analysis / Q000378:metabolism
D000485:Allergens; D050683:R-SNARE Proteins; D017455:Receptors, IgE; C496927:Sybl1 protein, mouse; D012701:Serotonin; D007073:Immunoglobulin E