Mast cells form antibody-dependent degranulatory synapse for dedicated secretion and defence

Nat Commun. 2015 Jan 28;6:6174. doi: 10.1038/ncomms7174.

 

Joulia R¹, Gaudenzio N¹, Rodrigues M¹, Lopez J¹, Blanchard N¹, Valitutti S¹, Espinosa E¹.

 

Mast cells are tissue-resident immune cells that play a key role in inflammation and allergy. Here we show that interaction of mast cells with antibody-targeted cells induces the polarized exocytosis of their granules resulting in a sustained exposure of effector enzymes, such as tryptase and chymase, at the cell-cell contact site. This previously unidentified mast cell effector mechanism, which we name the antibody-dependent degranulatory synapse (ADDS), is triggered by both IgE- and IgG-targeted cells. ADDSs take place within an area of cortical actin cytoskeleton clearance in the absence of microtubule organizing centre and Golgi apparatus repositioning towards the stimulating cell. Remarkably, IgG-mediated degranulatory synapses also occur upon contact with opsonized Toxoplasma gondii tachyzoites resulting in tryptase-dependent parasite death. Our results broaden current views of mast cell degranulation by revealing that human mast cells form degranulatory synapses with antibody-targeted cells and pathogens for dedicated secretion and defence.

PMID:

25629393

[PubMed - in process]