scholarly journals Mammalian Granulocyte–Macrophage Colony-stimulating Factor Receptor Expressed in Primary Avian Hematopoietic Progenitors: Lineage-specific Regulation of Proliferation and Differentiation

1998 ◽  
Vol 141 (4) ◽  
pp. 1041-1051
Author(s):  
Oliver Wessely ◽  
Eva-Maria Deiner ◽  
Kim Chew Lim ◽  
Georg Mellitzer ◽  
Peter Steinlein ◽  
...  

The cytokine Granulocyte–Macrophage Colony-Stimulating Factor (GM-CSF) regulates proliferation, differentiation, and apoptosis during myelopoiesis and erythropoiesis. Structure–function relationships of GM-CSF interactions with its receptor (GM-R), the biochemistry of GM-R signal transduction, and GM-CSF action in vivo are relatively well understood. Much less is known, however, about GM-R function in primary hematopoietic cells. In this paper we show that expression of the human GM-R in a heterologous cell system (primary avian erythroid and myeloid cells) confirms respective results in murine or human cell lines, but also provides new insights how the GM-R regulates progenitor proliferation and differentiation. As expected, the hGM-CSF stimulated myeloid progenitor proliferation and differentiation and enhanced erythroid progenitor proliferation during terminal differentiation. In the latter cells, however, the hGM-R only partially substituted for the activities of the erythropoietin receptor (EpoR). It failed to replace the EpoR in its cooperation with c-Kit to induce long-term proliferation of erythroid progenitors. Furthermore, the hGM-R α chain specifically interfered with EpoR signaling, an activity neither seen for the βc subunit of the receptor complex alone, nor for the α chain of the closely related Interleukin-3 receptor. These results point to a novel role of the GM-R α chain in defining cell type–specific functions of the GM-R.

Blood ◽  
2002 ◽  
Vol 99 (7) ◽  
pp. 2603-2605 ◽  
Author(s):  
Armin G. Jegalian ◽  
Adriana Acurio ◽  
Glenn Dranoff ◽  
Hong Wu

Erythropoietin (EPO) and its receptor (EPOR) are critical for definitive erythropoiesis, as mice lacking either gene product die during embryogenesis with severe anemia. Here we demonstrate that mice expressing just one functional allele of the EpoR have lower hematocrits and die more frequently than do wild-type littermates on anemia induction. Furthermore, EpoR+/−erythroid colony-forming unit (CFU-E) progenitors are reduced both in frequency and in responsiveness to EPO stimulation. To evaluate the interaction between EPO and granulocyte-macrophage colony-stimulating factor (GM-CSF) or interleukin 3 (IL-3),GM-CSF−/− orIL-3−/− mice were interbred withEpoR+/− mice. Deletion of either GM-CSF or IL-3 also leads to reduction in CFU-E numbers and hematocrits but does not significantly alter steady-state erythroid burst-forming unit numbers. These results suggest EpoR haploinsufficiency and promotion of in vivo erythropoiesis by GM-CSF and IL-3.


Blood ◽  
1987 ◽  
Vol 70 (4) ◽  
pp. 965-973 ◽  
Author(s):  
MT Mitjavila ◽  
JL Villeval ◽  
P Cramer ◽  
A Henri ◽  
J Gasson ◽  
...  

Abstract Erythroid colonies from five patients with an early erythroblastic leukemia were obtained in “serum-free” cultures in the presence or absence of recombinant granulocyte-macrophage colony-stimulating factor (GM-CSF) and homogeneous native erythropoietin (Epo). Erythroid colonies with abnormal morphology and karyotype could be grown in different culture conditions. Their erythroid nature was ascertained by the presence of carbonic anhydrase I and glycophorin A. Leukemic erythroid progenitors strongly differed from normal progenitors in that spontaneous colonies were always obtained, sometimes with an extremely high plating efficiency (up to 5.7%). Colonies were found to be autonomous from exogenous hematopoietic growth factors because they were still obtained with a high plating efficiency at an average of one cell per culture in the absence of any added growth factor. No evidence for an autocrine secretion of Epo or GM-CSF emerged because Epo or GM- CSF could not be detected by biologic or radioimmunologic assays from the culture supernatant or cellular extracts of the leukemic cells and that Epo or GM-CSF antibodies did not block autonomous growth. In all cases, however, hematopoietic growth factors increased the plating efficiency of the abnormal erythroid progenitors. In the two “de novo” leukemias, leukemic erythroid progenitors responded primarily to Epo, whereas in the three other patients' (chronic myeloid leukemia) blast crisis they responded maximally to GM-CSF plus Epo. Recombinant erythroid-potentiating activity had no effect in any of these cases. These results suggest that the leukemic erythroid clonogenic cells arise from expansion of erythroid progenitors at different levels of differentiation (ie, CFU-E or BFU-E, depending upon the disease) and that autonomous growth is not related to a secretion of Epo or GM-CSF.


Blood ◽  
1993 ◽  
Vol 81 (3) ◽  
pp. 587-591 ◽  
Author(s):  
PT Jubinsky ◽  
DG Nathan ◽  
DJ Wilson ◽  
CA Sieff

Abstract To identify domains in hematopoietic growth factor receptors that are important for signal transduction, a hybrid receptor (GMER) was constructed by splicing the DNA of the entire extracellular and transmembrane domains of the human granulocyte-macrophage colony- stimulating factor (GM-CSF) receptor alpha 2 subunit (GMR) to the cytoplasmic domain of the murine erythropoietin receptor (mEpoR). The hybrid receptor was introduced into the interleukin-3 factor-dependent murine hematopoietic cell line Ba/F3. Cells that expressed high receptor numbers were selected by cell sorting using phycoerythrin- labeled human GM-CSF. Immunoprecipitation of GMER from Ba/F3 cells showed a band with an Mr of 105,000 daltons. Human GM-CSF binding to Ba/F3 cells that expressed GMER showed a kd of 3.0 nmol/L and 475 binding sites/cell, while the same cells that expressed GMR had 300 sites/cell and a kd of 3.5 nmol/L. The proliferative response to GM-CSF of Ba/F3 cells that expressed GMER showed 1/2 maximal cell growth (as measured by 3H-thymidine incorporation) at a GM-CSF concentration of 2.5 x 10(-8) mol/L. When cultured in human GM-CSF, Ba/F3-GMER cells expressed cell surface glycophorin. Similar results were obtained with Ba/F3 cells transfected with the mEpoR and cultured in erythropoietin. Expression of GMR plus the human GM-CSF receptor beta chain in the same cell line also resulted in human GM-CSF stimulated proliferation; however, cell surface glycophorin was not detected. These data show that a low-affinity GM-CSF/Epo hybrid receptor can promote GM-CSF- dependent proliferation and can induce the expression of glycophorin, an erythroid-specific protein.


Blood ◽  
1993 ◽  
Vol 81 (3) ◽  
pp. 587-591 ◽  
Author(s):  
PT Jubinsky ◽  
DG Nathan ◽  
DJ Wilson ◽  
CA Sieff

To identify domains in hematopoietic growth factor receptors that are important for signal transduction, a hybrid receptor (GMER) was constructed by splicing the DNA of the entire extracellular and transmembrane domains of the human granulocyte-macrophage colony- stimulating factor (GM-CSF) receptor alpha 2 subunit (GMR) to the cytoplasmic domain of the murine erythropoietin receptor (mEpoR). The hybrid receptor was introduced into the interleukin-3 factor-dependent murine hematopoietic cell line Ba/F3. Cells that expressed high receptor numbers were selected by cell sorting using phycoerythrin- labeled human GM-CSF. Immunoprecipitation of GMER from Ba/F3 cells showed a band with an Mr of 105,000 daltons. Human GM-CSF binding to Ba/F3 cells that expressed GMER showed a kd of 3.0 nmol/L and 475 binding sites/cell, while the same cells that expressed GMR had 300 sites/cell and a kd of 3.5 nmol/L. The proliferative response to GM-CSF of Ba/F3 cells that expressed GMER showed 1/2 maximal cell growth (as measured by 3H-thymidine incorporation) at a GM-CSF concentration of 2.5 x 10(-8) mol/L. When cultured in human GM-CSF, Ba/F3-GMER cells expressed cell surface glycophorin. Similar results were obtained with Ba/F3 cells transfected with the mEpoR and cultured in erythropoietin. Expression of GMR plus the human GM-CSF receptor beta chain in the same cell line also resulted in human GM-CSF stimulated proliferation; however, cell surface glycophorin was not detected. These data show that a low-affinity GM-CSF/Epo hybrid receptor can promote GM-CSF- dependent proliferation and can induce the expression of glycophorin, an erythroid-specific protein.


Blood ◽  
1987 ◽  
Vol 70 (4) ◽  
pp. 965-973
Author(s):  
MT Mitjavila ◽  
JL Villeval ◽  
P Cramer ◽  
A Henri ◽  
J Gasson ◽  
...  

Erythroid colonies from five patients with an early erythroblastic leukemia were obtained in “serum-free” cultures in the presence or absence of recombinant granulocyte-macrophage colony-stimulating factor (GM-CSF) and homogeneous native erythropoietin (Epo). Erythroid colonies with abnormal morphology and karyotype could be grown in different culture conditions. Their erythroid nature was ascertained by the presence of carbonic anhydrase I and glycophorin A. Leukemic erythroid progenitors strongly differed from normal progenitors in that spontaneous colonies were always obtained, sometimes with an extremely high plating efficiency (up to 5.7%). Colonies were found to be autonomous from exogenous hematopoietic growth factors because they were still obtained with a high plating efficiency at an average of one cell per culture in the absence of any added growth factor. No evidence for an autocrine secretion of Epo or GM-CSF emerged because Epo or GM- CSF could not be detected by biologic or radioimmunologic assays from the culture supernatant or cellular extracts of the leukemic cells and that Epo or GM-CSF antibodies did not block autonomous growth. In all cases, however, hematopoietic growth factors increased the plating efficiency of the abnormal erythroid progenitors. In the two “de novo” leukemias, leukemic erythroid progenitors responded primarily to Epo, whereas in the three other patients' (chronic myeloid leukemia) blast crisis they responded maximally to GM-CSF plus Epo. Recombinant erythroid-potentiating activity had no effect in any of these cases. These results suggest that the leukemic erythroid clonogenic cells arise from expansion of erythroid progenitors at different levels of differentiation (ie, CFU-E or BFU-E, depending upon the disease) and that autonomous growth is not related to a secretion of Epo or GM-CSF.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Jani Lappalainen ◽  
Nicolas Yeung ◽  
Su D. Nguyen ◽  
Matti Jauhiainen ◽  
Petri T. Kovanen ◽  
...  

AbstractIn atherosclerotic lesions, blood-derived monocytes differentiate into distinct macrophage subpopulations, and further into cholesterol-filled foam cells under a complex milieu of cytokines, which also contains macrophage-colony stimulating factor (M-CSF) and granulocyte–macrophage-colony stimulating factor (GM-CSF). Here we generated human macrophages in the presence of either M-CSF or GM-CSF to obtain M-MØ and GM-MØ, respectively. The macrophages were converted into cholesterol-loaded foam cells by incubating them with acetyl-LDL, and their atheroinflammatory gene expression profiles were then assessed. Compared with GM-MØ, the M-MØ expressed higher levels of CD36, SRA1, and ACAT1, and also exhibited a greater ability to take up acetyl-LDL, esterify cholesterol, and become converted to foam cells. M-MØ foam cells expressed higher levels of ABCA1 and ABCG1, and, correspondingly, exhibited higher rates of cholesterol efflux to apoA-I and HDL2. Cholesterol loading of M-MØ strongly suppressed the high baseline expression of CCL2, whereas in GM-MØ the low baseline expression CCL2 remained unchanged during cholesterol loading. The expression of TNFA, IL1B, and CXCL8 were reduced in LPS-activated macrophage foam cells of either subtype. In summary, cholesterol loading converged the CSF-dependent expression of key genes related to intracellular cholesterol balance and inflammation. These findings suggest that transformation of CSF-polarized macrophages into foam cells may reduce their atheroinflammatory potential in atherogenesis.


Neonatology ◽  
2021 ◽  
pp. 1-7
Author(s):  
Verena Schulte ◽  
Alexandra Sipol ◽  
Stefan Burdach ◽  
Esther Rieger-Fackeldey

<b><i>Background:</i></b> The granulocyte-macrophage-colony-stimulating factor (GM-CSF) plays an important role in surfactant homeostasis. β<sub>C</sub> is a subunit of the GM-CSF receptor (GM-CSF-R), and its activation mediates surfactant catabolism in the lung. β<sub>IT</sub> is a physiological, truncated isoform of β<sub>C</sub> and is known to act as physiological inhibitor of β<sub>C</sub>. <b><i>Objective:</i></b> The aim of this study was to determine the ratio of β<sub>IT</sub> and β<sub>C</sub> in the peripheral blood of newborns and its association with the degree of respiratory failure at birth. <b><i>Methods:</i></b> We conducted a prospective cohort study in newborns with various degrees of respiratory impairment at birth. Respiratory status was assessed by a score ranging from no respiratory impairment (0) to invasive respiratory support (3). β<sub>IT</sub> and β<sub>C</sub> expression were determined in peripheral blood cells by real-time PCR. β<sub>IT</sub> expression, defined as the ratio of β<sub>IT</sub> and β<sub>C</sub>, was correlated with the respiratory score. <b><i>Results:</i></b> β<sub>IT</sub> expression was found in all 59 recruited newborns with a trend toward higher β<sub>IT</sub> in respiratory ill (score 2, 3) newborns than respiratory healthy newborns ([score 0, 1]; <i>p</i> = 0.066). Seriously ill newborns (score 3) had significantly higher β<sub>IT</sub> than healthy newborns ([score 0], <i>p</i> = 0.010). Healthy preterm infants had significantly higher β<sub>IT</sub> expression than healthy term infants (<i>p</i> = 0.019). <b><i>Conclusions:</i></b> β<sub>IT</sub> is expressed in newborns with higher expression in respiratory ill than respiratory healthy newborns. We hypothesize that β<sub>IT</sub> may have a protective effect in postnatal pulmonary adaptation acting as a physiological inhibitor of β<sub>C</sub> and, therefore, maintaining surfactant in respiratory ill newborns.


Sign in / Sign up

Export Citation Format

Share Document