scholarly journals Familial and congenital polycythemia in three unrelated families

Blood ◽  
1992 ◽  
Vol 79 (11) ◽  
pp. 3019-3030 ◽  
Author(s):  
PD Emanuel ◽  
CJ Eaves ◽  
VC Broudy ◽  
T Papayannopoulou ◽  
MR Moore ◽  
...  
Keyword(s):  
Genomic Dna ◽  
Southern Blot Analysis ◽  
Chromosomal Rearrangements ◽  
Colony Growth ◽  
Erythroid Progenitors ◽  
Epo Receptor ◽  
Functional Studies ◽  
Standard Assay ◽  
Or Gene

Abstract Three families with polycythemia inherited through apparently different modes are described. Secondary causes of polycythemia were ruled out. Erythropoietin (EPO) levels were normal or low, even after phlebotomy. In vitro erythroid colony growth in standard assay cultures containing EPO was normal; however, in the absence of added EPO, a few progenitors from most of the affected individuals were able to generate recognizable colonies of mature erythroblasts, although these were smaller and proportionately less numerous than seen in polycythemia vera (PV). To search for EPO-receptor changes as a possible pathophysiologic mechanism, we examined, by Southern blot analysis, genomic DNA samples from affected and nonaffected family members, as well as three patients with PV. Two different probes, derived from the human EPO-receptor, were used. We found no evidence for chromosomal rearrangements or gene amplification in hereditary polycythemia or PV patients. Further, no nucleotide sequences were found that were homologous to the Friend spleen focus-forming virus glycoprotein gp55, which has been shown to bind to and activate the murine EPO-receptor. Functional studies examining number and binding affinity of the EPO- receptor on erythroid progenitors from three hereditary polycythemia patients demonstrated no abnormalities. We conclude that the mechanism(s) for the erythrocytosis in familial and congenital polycythemia and in PV may not involve the EPO-receptor and, therefore, may result from alterations of postreceptor responses.

scholarly journals Familial and congenital polycythemia in three unrelated families

Blood ◽  
1992 ◽  
Vol 79 (11) ◽  
pp. 3019-3030
Author(s):  
PD Emanuel ◽  
CJ Eaves ◽  
VC Broudy ◽  
T Papayannopoulou ◽  
MR Moore ◽  
...  
Keyword(s):  
Genomic Dna ◽  
Southern Blot Analysis ◽  
Chromosomal Rearrangements ◽  
Colony Growth ◽  
Erythroid Progenitors ◽  
Epo Receptor ◽  
Functional Studies ◽  
Standard Assay ◽  
Or Gene

Three families with polycythemia inherited through apparently different modes are described. Secondary causes of polycythemia were ruled out. Erythropoietin (EPO) levels were normal or low, even after phlebotomy. In vitro erythroid colony growth in standard assay cultures containing EPO was normal; however, in the absence of added EPO, a few progenitors from most of the affected individuals were able to generate recognizable colonies of mature erythroblasts, although these were smaller and proportionately less numerous than seen in polycythemia vera (PV). To search for EPO-receptor changes as a possible pathophysiologic mechanism, we examined, by Southern blot analysis, genomic DNA samples from affected and nonaffected family members, as well as three patients with PV. Two different probes, derived from the human EPO-receptor, were used. We found no evidence for chromosomal rearrangements or gene amplification in hereditary polycythemia or PV patients. Further, no nucleotide sequences were found that were homologous to the Friend spleen focus-forming virus glycoprotein gp55, which has been shown to bind to and activate the murine EPO-receptor. Functional studies examining number and binding affinity of the EPO- receptor on erythroid progenitors from three hereditary polycythemia patients demonstrated no abnormalities. We conclude that the mechanism(s) for the erythrocytosis in familial and congenital polycythemia and in PV may not involve the EPO-receptor and, therefore, may result from alterations of postreceptor responses.

scholarly journals Autosomal dominant erythrocytosis caused by increased sensitivity to erythropoietin

Blood ◽  
1991 ◽  
Vol 78 (11) ◽  
pp. 3066-3069 ◽  
Author(s):  
E Juvonen ◽  
E Ikkala ◽  
F Fyhrquist ◽  
T Ruutu
Keyword(s):  
Autosomal Dominant ◽  
Family Members ◽  
Calf Serum ◽  
Methyl Cellulose ◽  
Colony Growth ◽  
Erythroid Progenitors ◽  
Obvious Effect ◽  
Increased Sensitivity ◽  
The Difference

Abstract We describe here a family with autosomal dominant erythrocytosis. In in vitro cultures, performed using the methyl cellulose assay, the number of erythroid colonies was normal or marginally increased when a standard concentration of erythropoietin (Epo) was used, but at lower Epo concentrations, the investigated persons formed more colonies than the controls. The difference was generally greater the lower the Epo concentration became. Some erythroid colony growth was seen even in the absence of any added Epo (apart from the minute concentration found in fetal calf serum), a phenomenon not seen in the controls. This finding indicates that the erythrocytosis in this family is caused by hypersensitivity of erythroid progenitors to Epo. The serum Epo concentration was low or low normal in all of the investigated family members, which is in good accordance with hypersensitivity to Epo. The erythrocytosis has not had any obvious effect on the health or life- span of the affected individuals. Many of them have reached an advanced age, and one of the affected family members has won several Olympic gold medals and world championships in endurance sports.

scholarly journals Two New EPO Receptor Mutations: Truncated EPO Receptors Are Most Frequently Associated With Primary Familial and Congenital Polycythemias

Blood ◽  
1997 ◽  
Vol 90 (5) ◽  
pp. 2057-2061 ◽  
Author(s):  
Robert Kralovics ◽  
Karel Indrak ◽  
Tomas Stopka ◽  
Brian W. Berman ◽  
Jaroslav F. Prchal ◽  
...  
Keyword(s):  
Polycythemia Vera ◽  
Cell Mass ◽  
Oxygen Affinity ◽  
Erythroid Progenitors ◽  
The Czech Republic ◽  
Epo Receptor ◽  
Caucasian Family ◽  
Oxygen Affinity Of Hemoglobin ◽  
Dose Responses

Abstract Primary polycythemias are caused by an acquired or inborn mutation affecting hematopoietic/erythroid progenitors that results in an abnormal response to hematopoietic cytokines. Primary familial and congenital polycythemia (PFCP; also known as familial erythrocytosis) is characterized by elevated red blood cell mass, low serum erythropoietin (EPO) level, normal oxygen affinity of hemoglobin, and typically autosomal dominant inheritance. In this study we screened for mutations in the cytoplasmic domain of the EPO receptor (EPOR; exons 7 and 8 of the EPOR gene) in 27 unrelated subjects with primary or unidentified polycythemia. Two new EPOR mutations were found, which lead to truncation of the EPOR similarly to previously described mutations in PFCP subjects. The first is a 7-bp deletion (del59855991) found in a Caucasian family from Ohio. The second mutation (5967insT) was found in a Caucasian family from the Czech Republic. In both cases the EPO dose responses of the erythroid progenitors of the affected subjects were examined to confirm the diagnosis of PFCP. In one of these families, the in vitro behavior of erythroid progenitors in serum-containing cultures without the addition of EPO mimicked the behavior of polycythemia vera progenitors; however, we show that antibodies against either EPO or the EPOR distinguish the in vitro growth abnormality of polycythemia vera erythroid progenitors from that seen in this particular PFCP family. We conclude that PFCP is a disorder that appears to be associated in some families with EPOR mutations. So far, most of the described EPOR mutations (6 out of 8) associated with PFCP result in an absence of the C-terminal negative regulatory domain of the receptor.

Autosomal dominant erythrocytosis caused by increased sensitivity to erythropoietin

Blood ◽  
1991 ◽  
Vol 78 (11) ◽  
pp. 3066-3069 ◽  
Author(s):  
E Juvonen ◽  
E Ikkala ◽  
F Fyhrquist ◽  
T Ruutu
Keyword(s):  
Autosomal Dominant ◽  
Family Members ◽  
Calf Serum ◽  
Methyl Cellulose ◽  
Colony Growth ◽  
Erythroid Progenitors ◽  
Obvious Effect ◽  
Increased Sensitivity ◽  
The Difference

We describe here a family with autosomal dominant erythrocytosis. In in vitro cultures, performed using the methyl cellulose assay, the number of erythroid colonies was normal or marginally increased when a standard concentration of erythropoietin (Epo) was used, but at lower Epo concentrations, the investigated persons formed more colonies than the controls. The difference was generally greater the lower the Epo concentration became. Some erythroid colony growth was seen even in the absence of any added Epo (apart from the minute concentration found in fetal calf serum), a phenomenon not seen in the controls. This finding indicates that the erythrocytosis in this family is caused by hypersensitivity of erythroid progenitors to Epo. The serum Epo concentration was low or low normal in all of the investigated family members, which is in good accordance with hypersensitivity to Epo. The erythrocytosis has not had any obvious effect on the health or life- span of the affected individuals. Many of them have reached an advanced age, and one of the affected family members has won several Olympic gold medals and world championships in endurance sports.

scholarly journals In vitro differentiation of human granulocyte/macrophage and erythroid progenitors: comparative analysis of the influence of recombinant human erythropoietin, G-CSF, GM-CSF, and IL-3 in serum-supplemented and serum- deprived cultures

Blood ◽  
1988 ◽  
Vol 72 (1) ◽  
pp. 248-256 ◽  
Author(s):  
G Migliaccio ◽  
AR Migliaccio ◽  
JW Adamson
Keyword(s):  
Recombinant Human Erythropoietin ◽  
Colony Growth ◽  
Culture Conditions ◽  
Dependent Manner ◽  
Erythroid Progenitors ◽  
Concentration Dependent Manner ◽  
Gm Csf ◽  
Human Erythropoietin ◽  
Normal Humans

Abstract The effects of recombinant human erythropoietin (Ep), granulocyte/macrophage (GM) and granulocyte (G) colony-stimulating factors (CSF), and interleukin-3 (IL-3) on erythroid burst and GM colony growth have been studied in fetal bovine serum (FBS)- supplemented and FBS-deprived culture. Sources of progenitor cells were nonadherent or nonadherent T-lymphocyte-depleted marrow or peripheral blood cells from normal humans. G-CSF, in concentrations up to 2.3 X 10(-10) mol/L, induced only the formation of neutrophil colonies. In contrast, GM-CSF and IL-3 both induced GM colonies and sustained the formation of erythroid bursts in the presence of Ep. However, the activities of these growth factors were affected by the culture conditions. IL-3 induction of GM colonies depended on the presence of FBS, whereas the degree of GM-CSF induction of GM colonies in FBS- deprived cultures depended on the method by which adherent cells were removed. GM-CSF increased colony numbers in a concentration-dependent manner only if the cells had been prepared by overnight adherence. Both GM-CSF and IL-3 exhibited erythroid burst-promoting activity in FBS- deprived cultures. However, some lineage restriction was evident because GM-CSF was two- to threefold more active than IL-3 in inducing GM colonies but IL-3 was two- to threefold more active in promoting erythroid burst growth. Furthermore, in FBS-deprived cultures, the number of both erythroid bursts and GM colonies reached the maximum only when Ep, GM-CSF, and IL-3 or GM-CSF, IL-3, and G-CSF, respectively, were added together. These results suggest that the colonies induced by IL-3, GM-CSF, and G-CSF are derived from different progenitors.

scholarly journals Hormonal effects on cell proliferation in a human erythroleukemia cell line (K562)

Blood ◽  
1980 ◽  
Vol 56 (5) ◽  
pp. 886-891
Author(s):  
C Gauwerky ◽  
DW Golde
Keyword(s):  
Growth Hormone ◽  
Cell Proliferation ◽  
Colony Formation ◽  
Human Growth ◽  
K562 Cells ◽  
Colony Growth ◽  
Inhibitory Effect ◽  
Erythroid Progenitors ◽  
Adrenergic Antagonist

We have investigated the hormonal responsiveness of K562 cells using a serum-substituted in vitro clonogenic assay. Dexamethasone inhibited colony formation by the K562 cells, and the inhibitory effect could be reversed by progesterone (10(-6) M). Fluoxymesterone caused a prominent enhancement of K562 colony growth, whereas estriol had no effect. Stimulation by triiodothyronine was maximal at 10(-7) M, and the thyroid effect could be abrogated by the beta 2-adrenergic antagonist butoxamine in equimolar concentrations. Using standard tissue culture conditions, the beta-adrenergic agent isoproterenol, but not the alpha catecholamine phenylephrine, enhanced the proliferation of K562 cells. When K562 cells were grown under hormone-depleted conditions, they developed responsiveness to phenylephrine and were no longer stimulated by isoproterenol. DbcAMP and prostaglandins of the E series also caused K562 colony enhancement. Prostaglandin F2 alpha had no effect on cell proliferation. Insulin was an effective stimulant of colony formation of K562 cells, as were human growth hormone and ovine prolacin. Bovine growth hormone had no effect. Our results are consistent with the identificaiton of K562 as an erythroid line, and they indicate that K562 cells respond to endocrine hormones in a manner analogous to normal erythroid progenitors.

scholarly journals Identification of Pre-Gmps and Pre-Meps: Two Novel Types of Committed Progenitor Cells in Bone Marrow

Blood ◽  
2021 ◽  
Vol 138 (Supplement 1) ◽  
pp. 3266-3266
Author(s):  
Ryan Mack ◽  
Lei Zhang ◽  
Kanak Joshi ◽  
Shanhui Liu ◽  
Mark Sellin ◽  
...  
Keyword(s):  
Conflicts Of Interest ◽  
Erythroid Progenitors ◽  
Hematopoietic Stem ◽  
Effector Cells ◽  
Functional Studies ◽  
Lineage Differentiation ◽  
Reliable Marker ◽  
Relationship Of

Abstract Elucidating the stepwise differentiation processes that leads from multipotent hematopoietic stem cells to mature effector cells is critical for understanding both normal and neoplastic hematopoiesis. Early studies suggested that common myeloid progenitors (CMPs) are oligo-lineage hematopoietic progenitors that produce all lineages of myeloid cells, including granulocytes, monocytes, erythrocytes and megakaryocytes. CMPs do so by first giving rise to megakaryocyte-erythroid progenitors (MEPs) and granulocyte-monocyte progenitors (GMPs), two types of bi-lineage progenitors. However, this concept was challenged by several recent studies where single cell techniques demonstrated that CMPs, GMPs and MEPs are highly heterogenic. The existence of lineage-restricted subsets within the CMP population leads to questions about whether erythroid and megakaryocytic lineage commitment is actually initiated at the multipotent progenitor or CMP stage. During the past 15 years, several lineage-restricted subsets of progenitors have been separated out from CMP population, including monocyte-dendritic progenitors, megakaryocyte progenitors, and erythroid progenitors based on expression of CD115/Flt3, CD41/CD150, and CD105/CD150, respectively. However, the remaining CMP population is still highly heterogenic. Thus, further separation of functional subsets within the CMP compartment is required. By screening cell surface markers that can further separate CMPs, we have identified CD27 as a reliable marker to separate all megakaryocyte/erythrocyte-committed progenitors from granulocyte/monocyte-committed progenitors. In addition, we found that CD62L is only expressed on granulocyte/monocyte-committed progenitors. CD27 and CD62L co-staining can separate CMP into CD27 +CD62L +, CD27 +CD62L - and CD27 -CD62L - subsets. Biology and morphology study showed that CD27 +CD62L - cells are closely associated with GMPs, whereas CD27 -CD62L - cells are closely associated with MEPs. In vitro culture and in vivo transplantation functional studies demonstrated that 1) CD27 +CD62L + cells are pre-GMPs that give rise to FcGRII/III + GMPs and only produce granulocytes and monocytes; 2) CD27 -CD62L - cells are pre-MEPs that give rise to MEPs and primarily produce erythrocytes and megakaryocytes with minimal contribution to granulocytes and monocytes; 3) CD27 +CD62L - subset enriches cells with genuine CMP potential capable of producing GMPs, MEPs, and subsequent progeny. Taken together, we have identified two novel populations of committed progenitors that serve as intermediates between CMP-GMP and CMP-MEP commitment pathways. Identification of pre-GMPs and pre-MEPs fills in the gap between CMPs-GMPs and CMPs-MEPs, supporting the hierarchal relationship of myeloid lineage differentiation. Disclosures No relevant conflicts of interest to declare.

Effects of Hepcidin, Ferritin, and Iron Deprivation on Erythroid Colony Formation in Vitro.

Blood ◽  
2004 ◽  
Vol 104 (11) ◽  
pp. 3704-3704
Author(s):  
Robert T. Means ◽  
Gail A. Dallalio ◽  
Thomas W. Fleury
Keyword(s):  
Colony Formation ◽  
Interleukin 1 ◽  
Colony Growth ◽  
Limiting Factor ◽  
Red Cell ◽  
Erythroid Progenitors ◽  
Anemia Of Chronic Disease ◽  
Iron Deprivation ◽  
Erythropoietic Response

Abstract The anemia of chronic disease (ACD) results from a combination of three pathologic processes. In ACD, a modest shortening of red cell survival creates an increased demand for red cell production, which is not met because of an impaired erythropoietic response and defects in reticuloendothelial iron mobilization and utilization. The impaired erythropoietic response, in turn, has two components: a blunted erythropoietin response, and an impaired response of erythroid progenitors to erythropoietin. Recombinant human erythropoietin (rhEPO) can reverse this impaired progenitor response in vitro, and can also correct ACD in patients. These processes have generally been considered effects of the cytokines which mediate the immune and inflammatory response, such as tumor necrosis factor, interleukin-1, and the interferons. It has recently been proposed that hepcidin, a mediator of innate immunity with the iron regulatory properties, is the factor responsible for ACD. If this is the case, then hepcidin should be able to induce the pathophysiologic mechanisms implicated in ACD. We therefore evaluated the effects of hepcidin and associated phenomena on human CFU-E colony formation in vitro. All CFU-E cultures were performed in plasma clots in serum-containing medium with rhEPO 1 U/mL. Hepcidin at concentrations 10 ng/mL -10 μg/mL had no effect on CFU-E colony formation. A number of studies have demonstrated that increased hepcidin message expression and protein production are strongly associated with increases in serum ferritin concentrations, and so the effect of added ferritin on erythroid colony formation was studied. Neither ferritin nor apo-ferritin 10 – 1000 ng/mL had inhibitory effects on CFU-E colony formation. The effect of iron deprivation on erythroid colony formation was evaluated with using desferrioxamine. Desferrioxamine 0.01mM decreased CFU-E colony formation to 60% of control values, while higher concentrations completely ablated colony growth. In summary, hepcidin does not appear to inhibit CFU-E colony formation directly or indirectly through ferritin. It may exert such an effect by decreasing availability of iron for erythropoiesis; however, such a finding would be difficult to reconcile with the observed clinical response of ACD to rhEPO, given that iron availability is typically a limiting factor in the erythropoietic response to rhEPO. The role of hepcidin in the overall pathogenesis of ACD remains to be fully determined.

scholarly journals Hormonal effects on cell proliferation in a human erythroleukemia cell line (K562)

Blood ◽  
1980 ◽  
Vol 56 (5) ◽  
pp. 886-891 ◽  
Author(s):  
C Gauwerky ◽  
DW Golde
Keyword(s):  
Growth Hormone ◽  
Cell Proliferation ◽  
Colony Formation ◽  
Human Growth ◽  
K562 Cells ◽  
Colony Growth ◽  
Inhibitory Effect ◽  
Erythroid Progenitors ◽  
Adrenergic Antagonist

Abstract We have investigated the hormonal responsiveness of K562 cells using a serum-substituted in vitro clonogenic assay. Dexamethasone inhibited colony formation by the K562 cells, and the inhibitory effect could be reversed by progesterone (10(-6) M). Fluoxymesterone caused a prominent enhancement of K562 colony growth, whereas estriol had no effect. Stimulation by triiodothyronine was maximal at 10(-7) M, and the thyroid effect could be abrogated by the beta 2-adrenergic antagonist butoxamine in equimolar concentrations. Using standard tissue culture conditions, the beta-adrenergic agent isoproterenol, but not the alpha catecholamine phenylephrine, enhanced the proliferation of K562 cells. When K562 cells were grown under hormone-depleted conditions, they developed responsiveness to phenylephrine and were no longer stimulated by isoproterenol. DbcAMP and prostaglandins of the E series also caused K562 colony enhancement. Prostaglandin F2 alpha had no effect on cell proliferation. Insulin was an effective stimulant of colony formation of K562 cells, as were human growth hormone and ovine prolacin. Bovine growth hormone had no effect. Our results are consistent with the identificaiton of K562 as an erythroid line, and they indicate that K562 cells respond to endocrine hormones in a manner analogous to normal erythroid progenitors.

Critical role for PI 3-kinase in the control of erythropoietin-induced erythroid progenitor proliferation

Blood ◽  
2003 ◽  
Vol 101 (9) ◽  
pp. 3436-3443 ◽  
Author(s):  
Didier Bouscary ◽  
Frédéric Pene ◽  
Yann-Erick Claessens ◽  
Odile Muller ◽  
Stany Chrétien ◽  
...  
Keyword(s):  
Critical Role ◽  
Adaptor Protein ◽  
Erythroid Progenitors ◽  
Erythroid Progenitor ◽  
Alternative Pathways ◽  
Epo Receptor ◽  
Mitogen Activated Protein ◽  
Kinase Pathway

The production of red blood cells is tightly regulated by erythropoietin (Epo). The phosphoinositide 3–kinase (PI 3-kinase) pathway was previously shown to be activated in response to Epo. We studied the role of this pathway in the control of Epo-induced survival and proliferation of primary human erythroid progenitors. We show that phosphoinositide 3 (PI 3)–kinase associates with 4 tyrosine-phosphorylated proteins in primary human erythroid progenitors, namely insulin receptor substrate–2 (IRS2), Src homology 2 domain–containing inositol 5′-phosphatase (SHIP), Grb2-associated binder–1 (Gab1), and the Epo receptor (EpoR). Using different in vitro systems, we demonstrate that 3 alternative pathways independently lead to Epo-induced activation of PI 3-kinase and phosphorylation of its downstream effectors, Akt, FKHRL1, and P70S6 kinase: through direct association of PI 3-kinase with the last tyrosine residue (Tyr479) of the Epo receptor (EpoR), through recruitment and phosphorylation of Gab proteins via either Tyr343 or Tyr401 of the EpoR, or through phosphorylation of IRS2 adaptor protein. The mitogen-activated protein (MAP) kinase pathway was also activated by Epo in erythroid progenitors, but we found that this process is independent of PI 3-kinase activation. In erythroid progenitors, the functional role of PI 3-kinase was both to prevent apoptosis and to stimulate cell proliferation in response to Epo stimulation. Finally, our results show that PI 3-kinase–mediated proliferation of erythroid progenitors in response to Epo occurs mainly through modulation of the E3 ligase SCFSKP2, which, in turn, down-regulates p27Kip1 cyclin-dependent kinase (CDK) inhibitor via proteasome degradation.

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