@Article{,
AUTHOR = {Ying Gao, Hans Tapper, Jero Calafat, Inge Olsson, Markus Hansson},
TITLE = {Granule targeting of soluble tumor necrosis factor (TNF) receptor expressed during granulopoietic maturation in murine bone marrow cells},
JOURNAL = {European Cytokine Network},
VOLUME = {17},
YEAR = {2006},
NUMBER = {2},
PAGES = {98--108},
URL = {http://www.techscience.com/ECN/v17n2/66155},
ISSN = {1952-4005},
ABSTRACT = {In this experiment, we explored the potential of secretory lysosomes of hematopoietic cells to act as
vehicles for immunomodulatory protein delivery at an inflammation site. We investigated whether exogenous
soluble TNF-receptor 1 (sTNFR1) could be expressed in primary hematopoietic progenitor cells and become
targeted for storage and secretion during granulopoietic differentiation. An sTNFR1 construct with a transmembrane
domain (tm) and a cytosol sorting signal (Y) taken from CD63, was retrovirally transduced to
lineage-negative murine hematopoietic bone marrow stem/progenitor cells. This process was followed by
cytokine-driven granulopoietic maturation. The sTNFR1-tm-Y was found to be synthesized in precursor cells and
to persist in mature granulocytes and monocytes/macrophages. Immunofluorescence-localization studies showed
a granule pattern of sTNFR1-tm-Y in both precursor and mature granulocytes and secretion to phagosomes after
ingestion of bacteria. Immunoelectron microscopy revealed co-localization between the sTNFR1-tm-Y and the
primary (azurophil) granule marker myeloperoxidase. Collectively, our results demonstrated granule targeting,
storage, and secretion of exogenous sTNFR1-tm-Y constitutively expressed during normal granulopoietic
differentiation. These findings support the concept of using storage organelles of circulating hematopoietic cells as
vehicles for targeting sites of inflammation with immunoregulatory agents.In this experiment, we explored the potential of secretory lysosomes of hematopoietic cells to act as
vehicles for immunomodulatory protein delivery at an inflammation site. We investigated whether exogenous
soluble TNF-receptor 1 (sTNFR1) could be expressed in primary hematopoietic progenitor cells and become
targeted for storage and secretion during granulopoietic differentiation. An sTNFR1 construct with a transmembrane
domain (tm) and a cytosol sorting signal (Y) taken from CD63, was retrovirally transduced to
lineage-negative murine hematopoietic bone marrow stem/progenitor cells. This process was followed by
cytokine-driven granulopoietic maturation. The sTNFR1-tm-Y was found to be synthesized in precursor cells and
to persist in mature granulocytes and monocytes/macrophages. Immunofluorescence-localization studies showed
a granule pattern of sTNFR1-tm-Y in both precursor and mature granulocytes and secretion to phagosomes after
ingestion of bacteria. Immunoelectron microscopy revealed co-localization between the sTNFR1-tm-Y and the
primary (azurophil) granule marker myeloperoxidase. Collectively, our results demonstrated granule targeting,
storage, and secretion of exogenous sTNFR1-tm-Y constitutively expressed during normal granulopoietic
differentiation. These findings support the concept of using storage organelles of circulating hematopoietic cells as
vehicles for targeting sites of inflammation with immunoregulatory agents.},
DOI = {}
}