Bone formation by culture-expanded bone marrow cells exposed to growth factors in vitro and in vivo

Recently, it was shown that interleukin-1β (IL-1β) has diverse stimulatory effects on different murine long bone marrow osteoclast precursors (OCPs) in vitro. In this study, interleukin-1 receptor antagonist deficient (Il1rn−/−) and wild-type (WT) mice were compared to investigate the effects of enhanced IL-1 signaling on the composition of OCPs in long bone, calvaria, vertebra, and jaw. Bone marrow cells were isolated from these sites and the percentage of early blast (CD31hi Ly-6C−), myeloid blast (CD31+ Ly-6C+), and monocyte (CD31− Ly-6Chi) OCPs was assessed by flow cytometry. At the time-point of cell isolation, Il1rn−/− mice showed no inflammation or bone destruction yet as determined by histology and microcomputed tomography. However, Il1rn−/− mice had an approximately two-fold higher percentage of OCPs in long bone and jaw marrow compared to WT. Conversely, vertebrae and calvaria marrow contained a similar composition of OCPs in both strains. Bone marrow cells were cultured with macrophage colony stimulating factor (M-CSF) and receptor of NfκB ligand (RANKL) on bone slices to assess osteoclastogenesis and on calcium phosphate-coated plates to analyze mineral dissolution. Deletion of Il1rn increased osteoclastogenesis from long bone, calvaria, and jaw marrows, and all Il1rn−/− cultures showed increased mineral dissolution compared to WT. However, osteoclast markers increased exclusively in Il1rn−/− osteoclasts from long bone and jaw. Collectively, these findings indicate that a lack of IL-1RA increases the numbers of OCPs in vivo, particularly in long bone and jaw, where rheumatoid arthritis and periodontitis develop. Thus, increased bone loss at these sites may be triggered by a larger pool of OCPs due to the disruption of IL-1 inhibitors.

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Effect of Zinc Supplementation on Renal Anemia in 5/6-Nephrectomized Rats and a Comparison with Treatment with Recombinant Human Erythropoietin

International Journal of Molecular Sciences ◽

10.3390/ijms20204985 ◽

2019 ◽

Vol 20 (20) ◽

pp. 4985 ◽

Cited By ~ 2

Author(s):

Hui-Lin Feng ◽

Yen-Hua Chen ◽

Sen-Shyong Jeng

Keyword(s):

Bone Marrow ◽

Recombinant Human Erythropoietin ◽

Zinc Supplementation ◽

Bone Marrow Cells ◽

Human Erythropoietin ◽

Post Surgery ◽

Rat Bone ◽

Marrow Cells

Anemia is a severe complication in patients with chronic kidney disease (CKD). Treatment with exogenous erythropoietin (EPO) can correct anemia in many with CKD. We produced 5/6-nephrectomized rats that became uremic and anemic at 25 days post surgery. Injection of the anemic 5/6-nephrectomized rats with 2.8 mg zinc/kg body weight raised their red blood cell (RBC) levels from approximately 85% of the control to 95% in one day and continued for 4 days. We compared the effect of ZnSO4 and recombinant human erythropoietin (rHuEPO) injections on relieving anemia in 5/6-nephrectomized rats. After three consecutive injections, both the ZnSO4 and rHuEPO groups had significantly higher RBC levels (98 ± 6% and 102 ± 6% of the control) than the saline group (90 ± 3% of the control). In vivo, zinc relieved anemia in 5/6-nephrectomized rats similar to rHuEPO. In vitro, we cultured rat bone marrow cells supplemented with ZnCl2, rHuEPO, or saline. In a 4-day suspension culture, we found that zinc induced erythropoiesis similar to rHuEPO. When rat bone marrow cells were supplement-cultured with zinc, we found that zinc stimulated the production of EPO in the culture medium and that the level of EPO produced was dependent on the concentration of zinc supplemented. The production of EPO via zinc supplementation was involved in the process of erythropoiesis.

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Increases in circulating megakaryocyte growth-promoting activity in the plasma of rats following whole body irradiation

Blood ◽

10.1182/blood.v63.5.1060.1060 ◽

1984 ◽

Vol 63 (5) ◽

pp. 1060-1066 ◽

Cited By ~ 15

Author(s):

M Miura ◽

CW Jackson ◽

SA Lyles

Keyword(s):

Bone Marrow ◽

Plasma Concentration ◽

Bone Marrow Cells ◽

Single Cells ◽

Rat Plasma ◽

Whole Body ◽

Growth Promoting ◽

Marrow Cells

Abstract To gain insight into the regulation of megakaryocyte precursors in vivo, we assayed (in vitro) megakaryocyte growth-promoting activity (Meg-GPA) in plasma of rats in which both marrow hypoplasia and thrombocytopenia had been induced by irradiation. Rats received whole body irradiation of 834 rad from a 137Cs source. Plasma was collected at intervals of hours to days, up through day 21 postirradiation, and was tested, at a concentration of 30%, for Meg-GPA on bone marrow cells cultured in 1.1% methylcellulose with 5 X 10(-5) M 2-mercaptoethanol. With normal rat plasma, no megakaryocyte colonies (defined as greater than or equal to 4 megakaryocytes) were seen and only a few single megakaryocytes and clusters (defined as 2 or 3 megakaryocytes) were formed. Two peaks of plasma Meg-GPA were observed after irradiation. The first appeared at 12 hr, before any decrease in marrow megakaryocyte concentration or platelet count. The second occurred on days 10–14 after irradiation, after the nadir in megakaryocyte concentration and while platelet counts were at their lowest levels. A dose-response study of plasma concentration and megakaryocyte growth, using plasma collected 11 days postirradiation, demonstrated that patterns of megakaryocyte growth were related to plasma concentration; formation of single megakaryocytes was optimal over a range of 20%-30% plasma concentration, while cluster and colony formation were optimal at a plasma concentration of 30%. All forms of megakaryocyte growth were decreased with 40% plasma. There was a linear relationship between the number of bone marrow cells plated and growth of single cells, clusters, and colonies using a concentration of 30% plasma collected 11 days after irradiation. We conclude that irradiation causes time- related increases in circulating megakaryocyte growth-promoting activity. We suggest that the irradiated rat is a good model for studying the relationships between Meg-GPA and megakaryocyte and platelet concentration in vivo.

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Dissecting Proto-Oncogenic PIM Serine/Threonine Kinases in FLT3-ITDInduced Leukemogenesis: PIM1 Regulates CXCL12/CXCR4-Mediated Homing and Migration

Blood ◽

10.1182/blood.v112.11.3796.3796 ◽

2008 ◽

Vol 112 (11) ◽

pp. 3796-3796

Author(s):

Christelle Gasser ◽

Rebekka Grundler ◽

Laurent Brault ◽

Alec Bullock ◽

Tobias Dechow ◽

...

Keyword(s):

Bone Marrow ◽

Small Molecule ◽

Bone Marrow Cells ◽

Dominant Negative ◽

Cell Homing ◽

Threonine Kinases ◽

And Migration ◽

Marrow Cells

Abstract Previous work has shown that FLT3-ITD mediated leukemogenesis is associated with increased expression of PIM1 and PIM2 serine/threonine kinases. Here we show that retroviral expression of FLT3-ITD could not compensate impaired clonogenic in vitro growth of PIM1−/− bone marrow cells. Induction of a lethal myelo- and lymphoproliferative disorder by FLT3-ITD in vivo was independent of PIM2, but rather unexpectedly, lethally irradiated recipients could not be reconstituted with FLT3-ITD expressing bone marrow cells lacking PIM1. Transplants of CSFE-labeled PIM1−/− cells revealed an impaired homing capacity to bone marrow and spleen. Expression of lower surface CXCR4 levels (while maintaining normal total CXCR4 levels) in PIM1−/− bone marrow cells was associated with significantly reduced migration towards a CXCL12 gradient and impaired CXCL12-mediated intracellular Ca2+ release. Using siRNA-mediated knockdown, a small molecule PIM inhibitor, expression of a dominant-negative acting PIM1 mutant or re-expression of PIM1 in knockout cells, we observed that PIM1 activity was critical for CXCR4 surface expression. In vitro kinase assays and masspectrometric analysis further revealed that PIM1 directly phosphorylated serine 339 located in the CXCR4 intracellular domain known to be essential for proper receptor recycling. Interestingly, in leukemic blasts from acute myeloid leukemia (AML) patients, we found an association of increased PIM1 expression and high-level of surface CXCR4. In addition, treatment of the cells with a small molecule PIM inhibitor resulted in decreased surface CXCR4 expression in some patients. Our work suggests that PIM1 exerts its oncogenic activity not only by supporting proliferation and survival but also by regulation of cell homing and migration through direct modification of the CXCL12/CXCR4 axis. As CXCR4 is a key mediator of cancer stem cell homing and metastasis, targeting of PIM1 may offer new therapeutic avenues against tumor progression and relapse.

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HIF-1α is a negative regulator of plasmacytoid DC development in vitro and in vivo

Blood ◽

10.1182/blood-2012-03-417022 ◽

2012 ◽

Vol 120 (15) ◽

pp. 3001-3006 ◽

Cited By ~ 19

Author(s):

Andreas Weigert ◽

Benjamin Weichand ◽

Divya Sekar ◽

Weixiao Sha ◽

Christina Hahn ◽

...

Keyword(s):

Bone Marrow ◽

Cell Function ◽

Bone Marrow Cells ◽

Negative Regulator ◽

Low Oxygen ◽

Hematopoietic Stem ◽

Lineage Differentiation ◽

Marrow Cells

Abstract Hypoxia-inducible factors (HIFs) regulate hematopoiesis in the embryo and maintain hematopoietic stem cell function in the adult. How hypoxia and HIFs contribute to hematopoietic lineage differentiation in the adult is ill defined. Here we provide evidence that HIF-1 limits differentiation of precursors into plasmacytoid dendritic cells (pDCs). Low oxygen up-regulated inhibitor of DNA binding 2 (ID2) and suppressed Flt3-L–induced differentiation of bone marrow cells to pDCs in wild-type but not HIF-1αfl/fl LysM-Cre bone marrow cells. Moreover, pDC differentiated normally in hypoxic ID2−/− bone marrow cultures. Finally, we observed elevated pDC frequencies in bone marrow, blood, and spleen of HIF-1αfl/fl LysM-Cre and ID2−/−, but not HIF-2αfl/fl LysM-Cre mice. Our data indicate that the low oxygen content in the bone marrow might limit pDC development. This might be an environmental mechanism to restrict the numbers of these potentially autoreactive cells.

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