Objective: We have previously shown that Flt3 ligand (FL)/Flt3 signaling regulates hematopoietic cell migration by modulating the SDF1alpha/CXCR4 signaling pathway. Herein, we evaluated whether a functional interaction between SDF1alpha/CXCR4 signaling and internal tandem duplication (ITD) of Flt3 regulates aberrant hematopoietic survival. We also investigated molecular mechanisms responsible for enhanced migration to SDF1alpha as a result of ITD-Flt3 expression and whether ITD-Flt3 regulates hematopoietic cell trafficking.
Methods: Hematopoietic progenitor cell survival was determined using marrow cells retrovirally expressing ITD-Flt3 and stimulated with SDF1alpha. Migration, to SDF1alpha adhesion to vascular cell adhesion molecule-1, and in vivo homing were determined using Ba/F3 cells expressing ITD-Flt3 and transfected with dominant negative (DN) H-Ras.
Results: Addition of SDF1alpha significantly increased growth factor-independent proliferation of colony-forming unit granulocyte-macrophage induced by ITD-Flt3. Although a negative gradient of SDF1alpha inhibited migration regardless of the stimulation, a positive gradient of FL or ITD-Flt3 significantly increased cell migration even in the presence of a negative SDF1alpha gradient. Enhanced migration induced by ITD-Flt3 was inhibited by DN-H-Ras, whereas overexpression of a constitutive active form of H-Ras in wild-type Flt3-Ba/F3 cells significantly elevated migration to SDF1alpha. Despite enhanced migration to SDF1alpha, preincubation with FL or ITD-Flt3 overexpression significantly reduced homing of primary mouse bone marrow cells or Ba/F3 cells to bone marrow that was associated with significant reduction in adhesion to vascular cell adhesion molecule-1 and VLA4 expression.
Conclusion: Our results suggest that functional interactions between Flt3 and SDF1alpha/CXCR4 regulate oncogenic proliferation and migration of hematopoietic cells, which is mediated by Ras, and that Flt3 signaling regulates hematopoietic cell trafficking in vivo.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1016/j.exphem.2006.04.001 | DOI Listing |
Exp Eye Res
December 2024
Department of Ophthalmology, The Second Hospital of Jilin University, Changchun, Jilin Province, China. Electronic address:
The number of people suffering from type 2 diabetes (DM2) is increasing and over 30 percent of DM2 patients will develop diabetic retinopathy (DR). Available therapeutic approaches for DR have their limitations. It is of great significance to search for other effective alternate therapeutic approaches.
View Article and Find Full Text PDFIntroduction: In this study, we tested the hypothesis that pre-osteoclast signaling is key in triggering post-traumatic angiogenesis in alveolar bone via the SDF-1/CXCR4 pathway. Interruption of osteoclast differentiation through zoledronate (Zol) disrupts the crosstalk between pre-osteoclasts and endothelial cells, hindering the initial angiogenic reaction following dental trauma. This disruption could therefore play a role in the pathogenesis of medication-related osteonecrosis of the jaw (MRONJ).
View Article and Find Full Text PDFNano Converg
October 2024
Department of Biomedical Science, CHA University, Seongnam, Gyeonggi-Do, 13488, Republic of Korea.
With the severity of chronic kidney disease worldwide, strategies to recover renal function via tissue regeneration provide alternatives to kidney replacement therapy. To exclude side effects from direct cell transplantation, extracellular vesicles (EVs) are great substitutes representing paracrine cell signaling. To build three-dimensional structures for implantation into the 5/6 nephrectomy model by incorporating bioactive materials, including multifunctional EVs (mEVs), porous PMEZE/mEV scaffolds were developed in combination with edaravone (EDV; E) and mEV based on PMEZ scaffolds with PLGA (P), MH-RA (M), ECM (E), ZnO-ALA (Z).
View Article and Find Full Text PDFiScience
September 2024
Department of Lymphoma/ Myeloma, MD Anderson Cancer Center, Houston, TX, USA.
CXCR4 cell surface expression is critical for the homing of T regulatory (Treg) cells to the bone marrow (BM). We hypothesize that CXCR4 enrichment on Tregs cell surface may abbreviate their transit time to reach BM. Umbilical cord-blood CD25 Tregs underwent CXCR4 dual enrichment and expansion using the CRANE process to generate CXCR4-enriched Tregs (Treg) cells, which showed a faster migration across the Transwell membrane toward CXCL12/stromal cell-derived factor 1α (SDF1α) at 15, 30, and 60 min, when compared to unmanipulated Treg cells ( < 0.
View Article and Find Full Text PDFBiomed Mater
October 2024
CAS Key Laboratory of Nano-Bio Interface, Suzhou Institute of Nano-Tech and Nano-Bionics, Chinese Academy of Sciences, Suzhou 215123, People's Republic of China.
The extracellular matrix (ECM) plays a crucial role in maintaining cell morphology and facilitating intercellular signal transmission within the human body. ECM has been extensively utilized for tissue injury repair. However, the consideration of factor gradients during ECM preparation has been limited.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!