Granulocyte-macrophage colony-stimulating factor preferentially activates the 94-kD STAT5A and an 80-kD STAT5A isoform in human peripheral blood monocytes

Blood ◽  
1996 ◽  
Vol 88 (4) ◽  
pp. 1206-1214 ◽  
Author(s):  
RL Rosen ◽  
KD Winestock ◽  
G Chen ◽  
X Liu ◽  
L Hennighausen ◽  
...  
Keyword(s):  
Molecular Weight ◽  
Human Peripheral Blood ◽  
Janus Kinase ◽  
Lower Molecular Weight ◽  
Colony Stimulating Factor ◽  
Enhancer Element ◽  
Gm Csf ◽  
Macrophage Colony Stimulating Factor ◽  
Macrophage Colony ◽  
Stimulating Factor

Granulocyte-macrophage colony-stimulating factor (GM-CSF) induces immediate effects in monocytes by activation of the Janus kinase (JAK2) and STAT transcription factor (STAT5) pathway. Recent studies have identified homologues of STAT5, STAT5A, and STAT5B, as well as lower molecular weight variants of STAT5. To define the activation of the STAT5 homologues and lower molecular weight variant in human monocytes and monocytes differentiated into macrophages by culture in macrophage- CSF (M-CSF), we measured the GM-CSF induced tyrosine phosphorylation of STAT5A, STAT5B, and any lower molecular weight STAT5 isoforms. Freshly isolated monocytes expressed 94-kD STAT5A, 92-kD STAT5B, and an 80-kD STAT5A molecule. Whereas 94-kD STAT5A was clearly tyrosine phosphorylated and bound to the enhancer element, the gamma response region (GRR), of the Fc gamma RI gene, substantially less tyrosine phosphorylated STAT5B bound to the immobilized GRR element. Macrophages lost their ability to express the 80-kD STAT5A protein, but retained their ability to activate STAT5A. STAT5A-STAT5A homodimers and STAT5A- STAT5B heterodimers formed in response to GM-CSF. Therefore, activation of STAT5A predominates compared to STAT5B when assayed by direct immunoprecipitation and by evaluation of bound STATs to immobilized GRR. Selective activation of STAT5 homologues in addition to generation of lower molecular isoforms may provide specificity and control to genes expressed in response to cytokines such as GM-CSF.

scholarly journals Activation of JAK2 in Human Vascular Endothelial Cells by Granulocyte-Macrophage Colony-Stimulating Factor

Blood ◽  
1997 ◽  
Vol 89 (3) ◽  
pp. 863-872 ◽  
Author(s):  
Raffaella Soldi ◽  
Luca Primo ◽  
Maria Felice Brizzi ◽  
Fiorella Sanavio ◽  
Massimo Aglietta ◽  
...  
Keyword(s):  
Endothelial Cells ◽  
Tyrosine Kinase ◽  
Janus Kinase ◽  
Colony Stimulating Factor ◽  
Functional Program ◽  
Gm Csf ◽  
Macrophage Colony Stimulating Factor ◽  
Macrophage Colony ◽  
Β Chain ◽  
Stimulating Factor

Abstract Besides the regulation of hematopoiesis, granulocyte-macrophage colony-stimulating factor (GM-CSF) induces the expression of a functional program in endothelial cells (ECs) related to angiogenesis and to their survival in the bone marrow microenvironment. ECs express specific GM-CSF high-affinity binding sites, which mediate the proliferative and migratory response. We now report that ECs express the α and β subunits of GM-CSF receptor (GM-CSFR), and that GM-CSF is able to activate the Janus kinase (JAK)2, a member of the cytosolic tyrosine kinase family, which is known to mediate signals of several non–tyrosine kinase receptors. JAK2 tyrosine phoshorylation, as well as activation of its catalytic activity, is induced by subnanomolar concentrations of GM-CSF and occurs within 3 minutes of stimulation and persists at least for 10 minutes. The effect is specific as inferred by the lack of effect of heat-inactivated GM-CSF or neutralized by specific antibodies and by the finding that interleukin-5, which utilizes a specific α chain and the same β chain of GM-CSFR, does not phosphorylate JAK2. Furthermore, we show that the amount of JAK2 physically associated with GM-CSFR β chain is increased after GM-CSF stimulation and that GM-CSF triggers both β chain and JAK2 tyrosine phosphorylation. Taken together, these results suggest that biologic activities of GM-CSF in vascular endothelium may, in part, be elicited by GM-CSFR–mediated JAK2 activation.

scholarly journals Two Distinct Signaling Pathways Downstream of Janus Kinase 2 Play Redundant Roles for Antiapoptotic Activity of Granulocyte-Macrophage Colony-stimulating Factor

1999 ◽  
Vol 10 (11) ◽  
pp. 3959-3970 ◽  
Author(s):  
Rui Liu ◽  
Tohru Itoh ◽  
Ken-ichi Arai ◽  
Sumiko Watanabe
Keyword(s):  
Signaling Pathway ◽  
Janus Kinase ◽  
Janus Kinase 2 ◽  
Colony Stimulating Factor ◽  
Tyrosine Residues ◽  
Gm Csf ◽  
Macrophage Colony Stimulating Factor ◽  
Antiapoptotic Activity ◽  
Macrophage Colony ◽  
Stimulating Factor

Human granulocyte-macrophage colony-stimulating factor (hGM-CSF) induces proliferation and sustains the viability of the mouse interleukin-3-dependent cell line BA/F3 expressing the hGM-CSF receptor. Analysis of the antiapoptosis activity of GM-CSF receptor βc mutants showed that box1 but not the C-terminal region containing tyrosine residues is essential for GM-CSF-dependent antiapoptotic activity. Because βc mutants, which activate Janus kinase 2 but neither signal transducer and activator of transcription 5 nor the MAPK cascade sustain antiapoptosis activity, involvement of Janus kinase 2, excluding the above molecules, in antiapoptosis activity seems likely. GM-CSF activates phosphoinositide-3-OH kinase as well as Akt, and activation of both was suppressed by addition of wortmannin. Interestingly, wortmannin did not affect GM-CSF-dependent antiapoptosis, thus indicating that the phosphoinositide-3-OH kinase pathway is not essential for cell surivival. Analysis using the tyrosine kinase inhibitor genistein and a MAPK/extracellular signal-regulated kinase (ERK) kinase 1 inhibitor, PD98059, indicates that activation of either the genistein-sensitive signaling pathway or the PD98059-sensitive signaling pathway from βc may be sufficient to suppress apoptosis. Wild-type and a βc mutant lacking tyrosine residues can induce expression of c-myc andbcl-xLgenes; however, drug sensitivities for activation of these genes differ from those for antiapoptosis activity of GM-CSF, which means that these gene products may be involved yet are inadequate to promote cell survival.

scholarly journals Production of granulocyte-macrophage colony-stimulating factor by large granular lymphocytes stimulated with Candida albicans: role in activation of human neutrophil function

Blood ◽  
1991 ◽  
Vol 77 (10) ◽  
pp. 2259-2265 ◽  
Author(s):  
DK Blanchard ◽  
MB Michelini-Norris ◽  
JY Djeu
Keyword(s):  
Candida Albicans ◽  
Mononuclear Cells ◽  
Human Peripheral Blood ◽  
Yeast Cells ◽  
Colony Stimulating Factor ◽  
Gm Csf ◽  
Macrophage Colony Stimulating Factor ◽  
Macrophage Colony ◽  
Stimulating Factor ◽  
Granular Lymphocytes

In the present study, culture supernatants from larger granular lymphocytes (LGL) that were activated with Candida albicans antigens were shown to stimulate the ability of neutrophils to inhibit fungal growth. Identification of the activation factors showed that granulocyte-macrophage colony-stimulating factor (GM-CSF), a hematopoietic growth factor, was involved. Human peripheral blood mononuclear cells were fractionated by Percoll density centrifugation and each subpopulation of cells was stimulated with C albicans yeast cells. GM-CSF was produced in those fractions enriched for LGL, but not T lymphocytes or adherent monocytes. Additionally, the phenotype of the GM-CSF-producing cell was found to be CD2+, CD16+, HLA-DR+, and negative for CD4, CD8, and CD15. Kinetic studies demonstrated that GM- CSF appeared in the supernatants within 2 days of culture and continued to be produced up to 7 days. Optimal stimulation of LGL was seen at a ratio of 3 heat-killed C albicans yeast cells per LGL. Thus, LGL play an important role in host defense against this opportunistic pathogen by producing cytokines, including GM-CSF, which in turn activates the fungicidal activity of neutrophils.

scholarly journals Expression of mRNA and immunoreactivity for the granulocyte/macrophage colony-stimulating factor in activated human eosinophils.

1991 ◽  
Vol 174 (3) ◽  
pp. 749-752 ◽  
Author(s):  
R Moqbel ◽  
Q Hamid ◽  
S Ying ◽  
J Barkans ◽  
A Hartnell ◽  
...  
Keyword(s):  
Human Peripheral Blood ◽  
Allergic Inflammation ◽  
Calcium Ionophore ◽  
Calcium Ionophore A23187 ◽  
Ionophore A23187 ◽  
Colony Stimulating Factor ◽  
Gm Csf ◽  
Macrophage Colony Stimulating Factor ◽  
Macrophage Colony ◽  
Stimulating Factor

Using in situ hybridization, we have shown that activated human peripheral blood eosinophils express mRNA for granulocyte/macrophage colony-stimulating factor (GM-CSF). Between 15 and 27% of eosinophils gave positive hybridization signals for GM-CSF mRNA after stimulation with the calcium ionophore A23187 or interferon gamma, and 4 and 6% after incubation with interleukin 3 (IL-3) or IL-5. Activated eosinophils also gave specific immunoreactivity with an anti-GM-CSF polyclonal antibody, suggesting translation of the mRNA. These data indicate that eosinophils may be an important source of GM-CSF at sites of allergic inflammation. Furthermore, the identification of GM-CSF production by human eosinophils suggests that the pro-inflammatory potential of this cell type may be substantially greater than hitherto recognized.

scholarly journals Association of granulocyte-macrophage colony-stimulating factor with the crystalloid granules of human eosinophils

Blood ◽  
1995 ◽  
Vol 85 (9) ◽  
pp. 2579-2586 ◽  
Author(s):  
F Levi-Schaffer ◽  
P Lacy ◽  
NJ Severs ◽  
TM Newman ◽  
J North ◽  
...  
Keyword(s):  
Plasma Membrane ◽  
Human Peripheral Blood ◽  
Colony Stimulating Factor ◽  
Dot Blot ◽  
Gm Csf ◽  
Macrophage Colony Stimulating Factor ◽  
Macrophage Colony ◽  
Eosinophil Granule ◽  
Blood Eosinophils ◽  
Stimulating Factor

We have previously shown that normal-density human peripheral blood eosinophils transcribe and translate mRNA for granulocyte-macrophage colony-stimulating factor (GM-CSF) and that the intracellular distribution was granular as assessed by light microscopy immunocytochemistry. The present study was conducted to confirm this apparent association between GM-CSF and the crystalloid granule using a subcellular fractionation method for human eosinophils and immunogold electron microscopy (EM). Highly purified (> 99%, by negative selection using anti-CD16 immunomagnetic microbeads) human peripheral blood eosinophils were obtained from four asthmatic subjects (not taking systemic medication), homogenized and density fractionated (5 x 10(7) cells/subject) on linear Nycodenz gradients. Twenty-four fractions were collected from each cell preparation and analyzed for marker enzyme activities as well as total protein. Dot blot analysis with specific monoclonal antibodies (MoAbs) was used to detect the eosinophil granule proteins major basic protein (MBP) and eosinophil cationic protein (ECP). An anti-CD9 MoAb was used as an eosinophil plasma membrane marker. Lactate dehydrogenase (LDH) was used as a cytosolic marker. Immunoreactivity for GM-CSF was detected by a specific enzyme-linked immunosorbent assay using a polyclonal antihuman GM-CSF antibody and confirmed by dot blot. GM-CSF coeluted with the cellular fractions containing granule markers (MBP, ECP, eosinophil peroxidase, hexosaminidase, and arylsulphatase), but not those containing cytoplasm (LDH+) or membrane (CD9+) markers. EM examination of pooled fractions associated with the peak of GM-CSF immunoreactivity confirmed that they contained crystalloid and small granules, but not plasma membrane. In addition, quantification, using immunogold labeling with an anti/GM-CSF MoAb, indicated preferential localization of gold particles over the eosinophil granule cores of intact cells. Thus, our results indicate that GM-CSF resides as a granule-associated, stored mediator in unstimulated human eosinophils.

scholarly journals Granulocyte/macrophage colony-stimulating factor and interleukin 3 release from human peripheral blood eosinophils and neutrophils.

1991 ◽  
Vol 174 (3) ◽  
pp. 745-748 ◽  
Author(s):  
H Kita ◽  
T Ohnishi ◽  
Y Okubo ◽  
D Weiler ◽  
J S Abrams ◽  
...  
Keyword(s):  
Peripheral Blood ◽  
Human Peripheral Blood ◽  
Calcium Ionophore ◽  
Colony Stimulating Factor ◽  
Interleukin 3 ◽  
Gm Csf ◽  
Macrophage Colony Stimulating Factor ◽  
Macrophage Colony ◽  
Blood Eosinophils ◽  
Stimulating Factor

Human peripheral blood eosinophils released eosinophil survival-enhancing activity when stimulated with the calcium ionophore, ionomycin. The release of activity was detected as early as 3 h after stimulation and was inhibited by an immunomodulating agent, cyclosporin A. The survival-enhancing activity was completely abolished by treatment with anti-interleukin 3 (IL-3) and anti-granulocyte/macrophage colony-stimulating factor (GM-CSF) monoclonal antibodies. Moreover, IL-3 and GM-CSF were measurable in ionomycin-stimulated eosinophil supernatants by immunoassay. Eosinophils produced approximately one-half as much IL-3 and one-fifth as much GM-CSF as ionomycin-stimulated mononuclear cells. Neutrophils also produced IL-3 and GM-CSF, but the amounts were less than those produced by eosinophils. These observations suggest a novel role for eosinophils in pathophysiology of allergic inflammation and host defense mechanisms.

scholarly journals Production of granulocyte-macrophage colony-stimulating factor by large granular lymphocytes stimulated with Candida albicans: role in activation of human neutrophil function

Blood ◽  
1991 ◽  
Vol 77 (10) ◽  
pp. 2259-2265 ◽  
Author(s):  
DK Blanchard ◽  
MB Michelini-Norris ◽  
JY Djeu
Keyword(s):  
Candida Albicans ◽  
Mononuclear Cells ◽  
Human Peripheral Blood ◽  
Yeast Cells ◽  
Colony Stimulating Factor ◽  
Gm Csf ◽  
Macrophage Colony Stimulating Factor ◽  
Macrophage Colony ◽  
Stimulating Factor ◽  
Granular Lymphocytes

Abstract In the present study, culture supernatants from larger granular lymphocytes (LGL) that were activated with Candida albicans antigens were shown to stimulate the ability of neutrophils to inhibit fungal growth. Identification of the activation factors showed that granulocyte-macrophage colony-stimulating factor (GM-CSF), a hematopoietic growth factor, was involved. Human peripheral blood mononuclear cells were fractionated by Percoll density centrifugation and each subpopulation of cells was stimulated with C albicans yeast cells. GM-CSF was produced in those fractions enriched for LGL, but not T lymphocytes or adherent monocytes. Additionally, the phenotype of the GM-CSF-producing cell was found to be CD2+, CD16+, HLA-DR+, and negative for CD4, CD8, and CD15. Kinetic studies demonstrated that GM- CSF appeared in the supernatants within 2 days of culture and continued to be produced up to 7 days. Optimal stimulation of LGL was seen at a ratio of 3 heat-killed C albicans yeast cells per LGL. Thus, LGL play an important role in host defense against this opportunistic pathogen by producing cytokines, including GM-CSF, which in turn activates the fungicidal activity of neutrophils.

scholarly journals Involvement of tyrosine kinases in the activation of human peripheral blood neutrophils by granulocyte-macrophage colony-stimulating factor

Blood ◽  
1991 ◽  
Vol 78 (7) ◽  
pp. 1842-1852 ◽  
Author(s):  
SR McColl ◽  
JF DiPersio ◽  
AC Caon ◽  
P Ho ◽  
PH Naccache
Keyword(s):  
Tyrosine Kinase ◽  
Tyrosine Phosphorylation ◽  
Human Peripheral Blood ◽  
Human Neutrophils ◽  
Dependent Manner ◽  
Colony Stimulating Factor ◽  
Gm Csf ◽  
Macrophage Colony Stimulating Factor ◽  
Macrophage Colony ◽  
Stimulating Factor

Abstract The aim of the present study is to evaluate the involvement of human neutrophil tyrosine kinase(s) in the signal transduction mechanism of granulocyte-macrophage colony-stimulating factor (GM-CSF). Stimulation of neutrophils with GM-CSF resulted in a time- and dose-dependent phosphorylation of several proteins having estimated molecular weights of approximately 40, 55, 74, 97, 118, and 155 Kd, detected by immunoblot using a monoclonal antibody directed against phosphotyrosine. GM-CSF-induced tyrosine phosphorylation was inhibited in a dose- and time-dependent manner by the tyrosine kinase inhibitor erbstatin. Using this inhibitor, we were able to correlate tyrosine phosphorylation with several functional effects of GM-CSF on human neutrophils. Pretreatment of neutrophils with erbstatin before incubation with GM-CSF completely inhibited the GM-CSF-induced intracellular alkalinization, downregulation of the leukotriene B4 receptor, enhancement of fMet-Leu-Phe-induced intracellular calcium mobilization, as well as the accumulation of mRNA for the proto- oncogene c-fos. Taken together, these data suggest that tyrosine kinase activation in human neutrophils plays a critical regulatory role in both the stimulation and priming of neutrophil function by GM-CSF.

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