Unknown

Dataset Information

0

Eosinophil granules function extracellularly as receptor-mediated secretory organelles.


ABSTRACT: Intracellular granules in several types of leukocytes contain preformed proteins whose secretions contribute to immune and inflammatory functions of leukocytes, including eosinophils, cells notably associated with asthma, allergic inflammation, and helminthic infections. Cytokines and chemokines typically elicit extracellular secretion of granule proteins by engaging receptors expressed externally on the plasma membranes of cells, including eosinophils. Eosinophil granules, in addition to being intracellular organelles, are found as intact membrane-bound structures extracellularly in tissue sites of eosinophil-associated diseases. Neither the secretory capacities of cell-free eosinophil granules nor the presence of functional cytokine and chemokine receptors on membranes of leukocyte granules have been recognized. Here, we show that granules of human eosinophils express membrane receptors for a cytokine, IFN-gamma, and G protein-coupled membrane receptors for a chemokine, eotaxin, and that these receptors function by activating signal-transducing pathways within granules to elicit secretion from within granules. Capacities of intracellular granule organelles to function autonomously outside of eosinophils as independent, ligand-responsive, secretion-competent structures constitute a novel postcytolytic mechanism for regulated secretion of eosinophil granule proteins that may contribute to eosinophil-mediated inflammation and immunomodulation.

SUBMITTER: Neves JS 

PROVIDER: S-EPMC2587599 | biostudies-literature | 2008 Nov

REPOSITORIES: biostudies-literature

altmetric image

Publications

Eosinophil granules function extracellularly as receptor-mediated secretory organelles.

Neves Josiane S JS   Perez Sandra A C SA   Spencer Lisa A LA   Melo Rossana C N RC   Reynolds Lauren L   Ghiran Ionita I   Mahmudi-Azer Salahaddin S   Odemuyiwa Solomon O SO   Dvorak Ann M AM   Moqbel Redwan R   Weller Peter F PF  

Proceedings of the National Academy of Sciences of the United States of America 20081118 47


Intracellular granules in several types of leukocytes contain preformed proteins whose secretions contribute to immune and inflammatory functions of leukocytes, including eosinophils, cells notably associated with asthma, allergic inflammation, and helminthic infections. Cytokines and chemokines typically elicit extracellular secretion of granule proteins by engaging receptors expressed externally on the plasma membranes of cells, including eosinophils. Eosinophil granules, in addition to being  ...[more]

Similar Datasets

| S-EPMC1440831 | biostudies-literature
| S-EPMC4478961 | biostudies-literature
| S-EPMC3192285 | biostudies-literature
| S-EPMC10834547 | biostudies-literature
| S-EPMC4337062 | biostudies-literature
| S-EPMC3596967 | biostudies-literature
| S-EPMC3986054 | biostudies-literature
| S-EPMC3529049 | biostudies-literature
| S-EPMC4119268 | biostudies-literature
| S-EPMC2576405 | biostudies-literature