... identified to play a crucial role in degranulation through the study of individuals harboring mutations in the gene encoding Rab27a. However, the guanine nucleotide exchange factor (GEF) regulating the activation of Rab27a in cytotoxic lymphocytes was unknown. Here, we show that knockout of MADD...

.... Following antigen stimulation, in RACK1 KD MCs, there was a reduction in cortical F-actin, an increase in monomeric G-actin and a failure to organize F-actin. RACK1 KD also increased and accelerated degranulation. CD63 + secretory granules were localized in F-actin-free cortical regions in non-stimulated...

...John R. Apgar ABSTRACT Rat basophilic leukemia cells will adhere to and spread out on fibronectin coated surfaces in an integrin dependent manner. Adhesion and spreading on fibronectin leads to increased degranulation, inositol phosphate production, phospholipase D activation, and increased...

...) at different rates compared to the rate at which they secrete chymase. We suggest that such a pattern of secretion exhibits a form of degranulation that permits the release of freely diffusible mediators that are loosely bound to granules, but only partially permits the secretion of insoluble mediators, which...

...William R. Henderson; Emil Y. Chi ABSTRACT Human eosinophil degranulation induced by the calcium ionophore A23187 was examined by transmission and scanning electron microscopy, and morphometric analysis. After incubation with A23187, eosinophil degranulation was characterized by granule movement...