Leucine rich α-2 glycoprotein: A novel neutrophil granule protein and modulator of myelopoiesis

Lawrence J. Druhan, Amanda Lance, Shimena Li, Andrea E. Price, Jacob T. Emerson, Sarah A. Baxter, Jonathan M. Gerber, Belinda R. Avalos

Research output: Contribution to journalArticlepeer-review

20 Scopus citations


Leucine-rich α2 glycoprotein (LRG1), a serum protein produced by hepatocytes, has been implicated in angiogenesis and tumor promotion. Our laboratory previously reported the expression of LRG1 in murine myeloid cell lines undergoing neutrophilic granulocyte differentiation. However, the presence of LRG1 in primary human neutrophils and a role for LRG1 in regulation of hematopoiesis have not been previously described. Here we show that LRG1 is packaged into the granule compartment of human neutrophils and secreted upon neutrophil activation to modulate the microenvironment. Using immunofluorescence microscopy and direct biochemical measurements, we demonstrate that LRG1 is present in the peroxidase-negative granules of human neutrophils. Exocytosis assays indicate that LRG1 is differentially glycosylated in neutrophils, and co-released with the secondary granule protein lactoferrin. Like LRG1 purified from human serum, LRG1 secreted from activated neutrophils also binds cytochrome c. We also show that LRG1 antagonizes the inhibitory effects of TGFβ1 on colony growth of human CD34+ cells and myeloid progenitors. Collectively, these data invoke an additional role for neutrophils in innate immunity that has not previously been reported, and suggest a novel mechanism whereby neutrophils may modulate the microenvironment via extracellular release of LRG1.

Original languageEnglish (US)
Article numbere0170261
JournalPloS one
Issue number1
StatePublished - Jan 2017

ASJC Scopus subject areas

  • General


Dive into the research topics of 'Leucine rich α-2 glycoprotein: A novel neutrophil granule protein and modulator of myelopoiesis'. Together they form a unique fingerprint.

Cite this