scholarly journals Paracrine Mechanisms of Intravenous Bone Marrow-Derived Mononuclear Stem Cells in Chronic Ischemic Stroke

2016 ◽  
Vol 6 (3) ◽  
pp. 107-119 ◽  
Author(s):  
Ashu Bhasin ◽  
M.V. Padma Srivastava ◽  
Sujata Mohanty ◽  
Sivasubramaniam Vivekanandhan ◽  
Sakshi Sharma ◽  
...  
Keyword(s):  
Stem Cells ◽  
Bone Marrow ◽  
Stem Cell ◽  
Ischemic Stroke ◽  
Growth Factors ◽  
Growth Factor ◽  
Stroke Patients ◽  
Bdnf Expression ◽  
Serious Adverse Events ◽  
Significant Difference

Background: The emerging role of stem cell technology and transplantation has helped scientists to study their potential role in neural repair and regeneration. The fate of stem cells is determined by their niche, consisting of surrounding cells and the secreted trophic growth factors. This interim report evaluates the safety, feasibility and efficacy (if any) of bone marrow-derived mononuclear stem cells (BM-MNC) in chronic ischemic stroke by studying the release of serum vascular endothelial growth factor (VEGF) and brain-derived neurotrophic growth factor (BDNF). Methods: Twenty stroke patients and 20 age-matched healthy controls were recruited with the following inclusion criteria: 3 months to 1.5 years from the index event, Medical Research Council (MRC) grade of hand muscles of at least 2, Brunnstrom stage 2-5, conscious, and comprehendible. They were randomized to one group receiving autologous BM-MNC (mean 60-70 million) and to another group receiving saline infusion (placebo). All patients were administered a neuromotor rehabilitation regime for 8 weeks. Clinical assessments [Fugl Meyer scale (FM), modified Barthel index (mBI), MRC grade, Ashworth tone scale] were carried out and serum VEGF and BDNF levels were assessed at baseline and at 8 weeks. Results: No serious adverse events were observed during the study. There was no statistically significant clinical improvement between the groups (FM: 95% CI 15.2-5.35, p = 0.25; mBI: 95% CI 14.3-4.5, p = 0.31). VEGF and BDNF expression was found to be greater in group 1 compared to group 2 (VEGF: 442.1 vs. 400.3 pg/ml, p = 0.67; BDNF: 21.3 vs. 19.5 ng/ml) without any statistically significant difference. Conclusion: Autologous mononuclear stem cell infusion is safe and tolerable by chronic ischemic stroke patients. The released growth factors (VEGF and BDNF) in the microenvironment could be due to the paracrine hypothesis of stem cell niche and neurorehabilitation regime.

Abstract WP146: Intravenous Bone Marrow Derived Mononuclear Stem Cells in Chronic Ischemic Stroke-Paracrine Mechanisms of Recovery

Stroke ◽  
2016 ◽  
Vol 47 (suppl_1) ◽  
Author(s):  
Ashu Bhasin ◽  
Padma Srivastava ◽  
Sujata mohanty ◽  
Vivekanandhan Subramaniyam ◽  
Senthil kumaran ◽  
...  
Keyword(s):  
Stem Cells ◽  
Bone Marrow ◽  
Stem Cell ◽  
Ischemic Stroke ◽  
Growth Factors ◽  
Growth Factor ◽  
Control Groups ◽  
Neural Repair ◽  
Traditional Concept ◽  
And Control

Background: The emerging role of Stem cell technology and transplantation has helped scientists to study its potential role in neural repair and regeneration. The fate of stem cells is determined by its niche, consisting of surrounding cells and the secreted trophic growth factors. This present study evaluates the safety, feasibility and efficacy of bone marrow derived mononuclear stem cells (BM-MNC) in chronic ischemic stroke by studying the release of serum vascular endothelial growth factor (VEGF) and brain derived neurotrophic growth factor (BDNF). Methods: Twenty (n=20) stroke patients recruited with the inclusion criteria as: 3 months to 1.5 years of index event, power of hand muscles atleast 2; Brunnstrom stage: 2-5; conscious and comprehendible, were randomized to study and control groups receiving autologous mean 60-70 million BM-MNC and controls receiving neuromotor rehabilitation regime only for 8 weeks. Clinical assessment (FM, mBI, MRC, Ashworth) and serum VEGF & BDNF were done at baseline and 8 weeks (2 months). Results: No patients exhibited any complication or adverse events during the whole procedure. There was no statistical significant clinical improvement between study and control groups (FM: 95%CI; 15.2 to 5.35, p=0.25; mBI : 95% CI;14.3 to 4.5, p=0.31). VEGF and BDNF were increased after stem cell infusion and exercise training in both the groups (VEGF: 442.1 pg/ml vs 400.3pg/ml; p=0.67; BDNF:95% CI∼15.09 to 4.09, p=0.57), without any statistical significant result. Conclusion: Autologous mononuclear stem cell infusion is safe and tolerable by chronic ischemic stroke. The paracrine hypothesis extends the traditional concept of stem cell niche to study the influence of stem cell released growth factors (VEGF and BDNF) on the microenvironment.

Are Amniotic Fluid Products Stem Cell Therapies? A Study of Amniotic Fluid Preparations for Mesenchymal Stem Cells With Bone Marrow Comparison

2019 ◽  
Vol 47 (5) ◽  
pp. 1230-1235 ◽  
Author(s):  
Alberto J. Panero ◽  
Alan M. Hirahara ◽  
Wyatt J. Andersen ◽  
Joshua Rothenberg ◽  
Fernando Fierro
Keyword(s):  
Stem Cells ◽  
Bone Marrow ◽  
Mesenchymal Stem Cells ◽  
Stem Cell ◽  
Growth Factors ◽  
Growth Factor ◽  
Amniotic Fluid ◽  
Enzyme Linked Immunosorbent Assay ◽  
Stem Cell Therapies ◽  
Cell Therapies

Background: In vivo amniotic fluid is known to contain a population of mesenchymal stem cells (MSCs) and growth factors and has been shown to assist in healing when used as an adjunct in procedures across multiple medical specialties. It is unclear whether amniotic fluid products (AFPs) contain MSCs and, if so, whether the cells remain viable after processing. Purpose: To determine whether MSCs, growth factors, and hyaluronan are present in commercially available AFPs. Study Design: Descriptive laboratory study. Methods: Seven commercial companies that provide amniotic fluid were invited to participate in the study; 3 companies (the manufacturers of PalinGen, FloGraft, and Genesis AFPs) agreed to participate and donated AFPs for analysis. The AFPs were evaluated for the presence of MSCs, various growth factors relevant to orthopaedics (platelet-derived growth factor ββ, vascular endothelial growth factor, interleukin 8, bone morphogenetic protein 2, transforming growth factor β1), and hyaluronan by enzyme-linked immunosorbent assay and culture of fibroblast colony-forming units. These products were compared with unprocessed amniotic fluid and 2 separate samples of MSCs derived from human bone marrow aspirates. All groups used the same culture medium and expansion techniques. Identical testing and analysis procedures were used for all samples. Results: MSCs could not be identified in the commercial AFPs or the unprocessed amniotic fluid. MSCs could be cultured from the bone marrow aspirates. Nucleated cells were found in 2 products (PalinGen and FloGraft), but most of these cells were dead. The few living cells did not exhibit established characteristics of MSCs. Growth factors and hyaluronan were present in all groups at varying levels. Conclusion: The AFPs studied should not be considered “stem cell” therapies, and researchers should use caution when evaluating commercial claims that products contain stem cells. Given their growth factor content, however, AFPs may still represent a promising tool for orthopaedic treatment. Clinical Relevance: Amniotic fluid has been proposed as an allogenic means for introducing MSCs. This study was unable to confirm that commercial AFPs contain MSCs.

scholarly journals A Comparison of Efficacy Following Two Different Doses of Granulocyte Colony Stimulating Factor (G-CSF) Alone for Mobilization of Peripheral Blood Stem Cells in 221 Multiple Myeloma Patients

Blood ◽  
2016 ◽  
Vol 128 (22) ◽  
pp. 5732-5732
Author(s):  
Soufi Osmani ◽  
Mohamed Brahimi ◽  
Souad Talhi ◽  
Kamila Amani ◽  
Hafida Ouldjeriouat ◽  
...  
Keyword(s):  
Stem Cells ◽  
Multiple Myeloma ◽  
Stem Cell ◽  
Growth Factors ◽  
Growth Factor ◽  
Conflicts Of Interest ◽  
Peripheral Blood Stem Cells ◽  
Hematopoietic Stem ◽  
Cd34 Cells ◽  
Significant Difference

Abstract Introduction: Intensive chemotherapy followed by autologous stem cell transplantation (ASCT) is currently the treatment of choice in multiple myeloma (MM). Mobilization of hematopoietic stem cell blood (HSCs) can be achieved either by the combination of chemotherapy plus growth factors or by growth factors alone. However, there is no consensus concerning the dose of growth factor alone that should be administered, with ranges varying from 5 microgr to 16 microgr/kg body weight. In this context, we report our experience in mobilization of HSCs using growth factor alone at the dose between 15 microgr /kg and 10 microgr /kg in MM. Patients and methods: A total of 340 ASCT were performed in our center, from May 2009 until June the 31st 2016. These concerned 221 patients with MM. Patients were hospitalized at day -5 on which mobilization started with G-CSF alone (filgrastim) at the dose of 15 microgr /kg/daily subcutaneously for 5 days from May 2009 to October 2012 and at the dose of 10 microgr /kg from November 2012 to June 2016. The white blood cell count was assessed daily. Apheresis was performed at day -2 and day -1 using a Spectra Optia CMN device, and the CD34+ count was assessed by flow cytometry. A single leukapheresis was performed if the number of CD34+ cells was above 2.106/kg. Failure of mobilization was defined as a level of CD34+ less than 2.106/kg, after two leukapheresis. In our study patients were divided into two groups: Group1 (G-CSF=15 microgr /kg) and Group 2 (G-CSF=10 microgr /kg) and the number of CD34+ were divided into three groups: optimal (³5.0 x 106 CD34+ cells/kg), suboptimal (2.0Ð5.0 x 106 CD34+ cells/kg) and poor (<2.0 x 106 CD34+ cells/kg) mobilization. Intensification was done using melphalan 200 mg/m2 on day -1. Results: Patient's characteristics are shown in Table 1. No significant difference was observed between the 2 groups. In this study, we found no significant difference in terms of optimal (p= 0.73), sub-optimal (p= 0.19) or poor (p= 0.11) harvest of stem cells between the 2 groups (table 2). Among the poor mobilizators with G-CSF, only 4 of them had a level of CD34+ harvest less than 0.5 x 106/kg. These patients did not receive an ASCT. 1,3% (4) of all apheresis failed to achieve acceptable harvest level. Conclusion: Our study showed that the mobilization regimen with G-CSF alone at the doses of 10 microgr/kg have the same efficacy as the doses of 15 microgr/kg and is interesting alternative to chemotherapy and G-CSF in patients with MM because it can be administered as an outpatient and is not associated with the risk of febrile neutropenia. Disclosures No relevant conflicts of interest to declare.

Growth factor treatment prior to low-dose total body irradiation increases donor cell engraftment after bone marrow transplantation in mice

Blood ◽  
2002 ◽  
Vol 100 (1) ◽  
pp. 312-317 ◽  
Author(s):  
Estelle J. K. Noach ◽  
Albertina Ausema ◽  
Jan H. Dillingh ◽  
Bert Dontje ◽  
Ellen Weersing ◽  
...  
Keyword(s):  
Stem Cells ◽  
Bone Marrow ◽  
Stem Cell ◽  
Growth Factors ◽  
Low Dose ◽  
Donor Cell ◽  
Hematopoietic Growth Factors ◽  
Cell Engraftment ◽  
Total Body

Abstract Low-toxicity conditioning regimens prior to bone marrow transplantation (BMT) are widely explored. We developed a new protocol using hematopoietic growth factors prior to low-dose total body irradiation (TBI) in recipients of autologous transplants to establish high levels of long-term donor cell engraftment. We hypothesized that treatment of recipient mice with growth factors would selectively deplete stem cells, resulting in successful long-term donor cell engraftment after transplantation. Recipient mice were treated for 1 or 7 days with growth factors (stem cell factor [SCF] plus interleukin 11 [IL-11], SCF plus Flt-3 ligand [FL], or granulocyte colony-stimulating factor [G-CSF]) prior to low-dose TBI (4 Gy). Donor cell chimerism was measured after transplantation of congenic bone marrow cells. High levels of donor cell engraftment were observed in recipients pretreated for 7 days with SCF plus IL-11 or SCF plus FL. Although 1-day pretreatments with these cytokines initially resulted in reduced donor cell engraftment, a continuous increase in time was observed, finally resulting in highly significantly increased levels of donor cell contribution. In contrast, G-CSF treatment showed no beneficial effects on long-term engraftment. In vitro stem cell assays demonstrated the effect of cytokine treatment on stem cell numbers. Donor cell engraftment and number of remaining recipient stem cells after TBI were strongly inversely correlated, except for groups treated for 1 day with SCF plus IL-11 or SCF plus FL. We conclude that long-term donor cell engraftment can be strongly augmented by treatment of recipient mice prior to low-dose TBI with hematopoietic growth factors that act on primitive cells.

scholarly journals Serum-mediated Activation of Bone Marrow–derived Mesenchymal Stem Cells in Ischemic Stroke Patients

2018 ◽  
Vol 27 (3) ◽  
pp. 485-500 ◽  
Author(s):  
Gyeong Joon Moon ◽  
Yeon Hee Cho ◽  
Dong Hee Kim ◽  
Ji Hee Sung ◽  
Jeong Pyo Son ◽  
...  
Keyword(s):  
Stem Cells ◽  
Bone Marrow ◽  
Mesenchymal Stem Cells ◽  
Growth Factor ◽  
Critical Role ◽  
Trophic Factors ◽  
Human Mscs ◽  
Stroke Patients ◽  
Serum Factors ◽  
Control Serum

Stroke induces complex and dynamic, local and systemic changes including inflammatory reactions, immune responses, and repair and recovery processes. Mesenchymal stem cells (MSCs) have been shown to enhance neurological recovery after stroke. We hypothesized that serum factors play a critical role in the activation of bone marrow (BM) MSCs after stroke such as by increasing proliferation, paracrine effects, and rejuvenation. Human MSCs (hMSCs) were grown in fetal bovine serum (FBS), normal healthy control serum (NS), or stroke patient serum (SS). MSCs cultured in growth medium with 10% SS or NS exhibited higher proliferation indices than those cultured with FBS ( P < 0.01). FBS-, NS-, and SS-hMSCs showed differences in the expression of trophic factors; vascular endothelial growth factor, glial cell–derived neurotrophic factor, and fibroblast growth factor were densely expressed in samples cultured with SS ( P < 0.01). In addition, SS-MSCs revealed different cell cycle– or aging-associated messenger RNA expression in a later passage, and β-galactosidase staining showed the senescence of MSCs observed during culture expansion was lower in MSCs cultured with SS than those cultured with NS or FBS ( P < 0.01). Several proteins related to the activity of receptors, growth factors, and cytokines were more prevalent in the serum of stroke patients than in that of normal subjects. Neurogenesis and angiogenesis were markedly increased in rats that had received SS-MSCs ( P < 0.05), and these rats showed significant behavioral improvements ( P < 0.01). Our results indicate that stroke induces a process of recovery via the activation of MSCs. Culture methods for MSCs using SS obtained during the acute phase of a stroke could constitute a novel MSC activation method that is feasible and efficient for the neurorestoration of stroke.

Abstract TP401: Inflated Expectations about Stem Cell Therapy in Patients With Chronic Stroke

Stroke ◽  
2013 ◽  
Vol 44 (suppl_1) ◽  
Author(s):  
Jinho Lee ◽  
Kyu-Yong Lee ◽  
Young-Seo Kim ◽  
Hyun Young Kim ◽  
Hyuk Sung Kwon ◽  
...  
Keyword(s):  
Stem Cells ◽  
Stem Cell ◽  
Ischemic Stroke ◽  
Cell Therapy ◽  
Stem Cell Therapy ◽  
Chronic Stroke ◽  
Accurate Information ◽  
Stroke Patients ◽  
Media Channels ◽  
Source Of Information

Introduction: Stem cell therapy (SCT) has been proposed for the treatment of neurological disorders. Although there isinsufficient clinical evidence to support its efficacy, unproven SCTs are being performed worldwide. Hypothesis: In this study, we investigated the perspectives and expectations of chronic ischemic stroke patients and physicians about SCTs. Methods: A total of 250 chronic ischemic stroke patients were interviewed at 4 hospitals. Structured open and closed questions about SCT for chronic stroke were asked by trained interviewers using the conventional in-person method. In addition, 250 stroke-related physicians were randomly interviewed via an e-mail questionnaire. Results: Of the 250 patients (mean 63 years, 70% male), 121 (46%) responded that they wanted to receive SCT in spite of its unknown side effects. Around 60% of the patients anticipated physical, emotional, and psychological improvement after SCT, and 158 (63%) believed that SCT might prevent strokes. However, physicians had much lower expectations about the effectiveness of SCTs, which was not in line with patient expectations. Multivariate analysis revealed that male gender (OR: 2.00, 95% CI: 1.10-3.64), longer disease duration (OR: 1.01, 95% CI:1.00-1.02), higher modified Rankin Scale score (OR: 1.30, 95% CI 1.06-1.60), and familiarity with stem cells (OR: 1.86, 95% CI: 1.10-3.15) were independently associated with wanting SCT. The major source of information about SCT was television (68%), and the most reliable source was physicians (49%). Conclusion: Patients have unfounded expectations that SCT will improve their functioning. Considering our finding that the major source of information on stem cells is media channels but not the physician, to decrease patients’ inappropriate exposure, doctors should make more effort to educate patients using mass media with accurate information.

scholarly journals Cyclophosphamide, Doxorubicin, Vincristine, Prednisone Dose Intensification With Granulocyte Colony-Stimulating Factor Markedly Depletes Stem Cell Reserve for Autologous Bone Marrow Transplantation

Blood ◽  
1997 ◽  
Vol 90 (12) ◽  
pp. 4996-5001 ◽  
Author(s):  
Arnold Freedman ◽  
Donna Neuberg ◽  
Peter Mauch ◽  
John Gribben ◽  
Robert Soiffer ◽  
...  
Keyword(s):  
Stem Cells ◽  
Stem Cell ◽  
Growth Factors ◽  
Growth Factor ◽  
Standard Dose ◽  
Granulocyte Colony Stimulating Factor ◽  
Colony Stimulating Factor ◽  
Dose Intensification ◽  
Sequential Trials ◽  
Stimulating Factor

Abstract Hematopoietic growth factors allow dose escalation of chemotherapy. This approach may potentially reduce the quality and quantity of hematopoietic stem cells. The capacity of stem cells recovered after dose intensification to support myeloablative therapy is unknown. In patients with previously untreated advanced follicular lymphoma, trilineage hematopoietic engraftment was compared in two sequential trials of induction therapy (standard dose cyclophosphamide, doxorubicin, vincristine, prednisone [CHOP] without growth factors or dose intensification CHOP supported by granulocyte colony-stimulating factor [G-CSF ]) followed by identical myeloablative therapy and autologous stem cell support. Neutrophil, platelet, and red blood cell (RBC) engraftment were compared on days 100, 180, and 360 after stem cell reinfusion. Despite similar patient characteristics including reinfusion of comparable numbers of marrow mononuclear cells, after stem cell transplantation, a highly significant prolongation of neutrophil and platelet engraftment was seen in patients who received high dose CHOP and G-CSF in comparison to standard dose CHOP. These findings suggest that dose intensified chemotherapy and G-CSF recruited stem cells into a proliferative phase and that G-CSF allowed retreatment at a time when stem cells were susceptible to damage by cytotoxic therapy. Such inadequate hematologic engraftment after myeloablative therapy might be avoided by either shortening the time that growth factor support is administered, lengthening the interval between cycles, or attempting to repetitively harvest additional stem cells either from the marrow or peripheral blood. Therefore, intensification of chemotherapy with growth factor support must be used with caution if stem cells are to be used to support myeloablative therapy.

The Effect of Prophylactic Administration of Myeloid Growth Factors Following Autologous Stem Cell Transplantation for Patients with Hematological Malignancies: A Systematic Review.

Blood ◽  
2004 ◽  
Vol 104 (11) ◽  
pp. 2192-2192
Author(s):  
Graeme A.M. Fraser ◽  
Ahmed Al-Sagheir ◽  
Donald M. Arnold ◽  
C. Tom Kouroukis ◽  
Ronan Foley ◽  
...  
Keyword(s):  
Stem Cell ◽  
Growth Factors ◽  
Growth Factor ◽  
Stem Cell Transplantation ◽  
Cell Transplantation ◽  
Autologous Stem Cell Transplantation ◽  
Early Administration ◽  
Post Transplant ◽  
Significant Difference ◽  
Duration Of Hospitalization

Abstract BACKGROUND. Myeloid growth factors (G-CSF, GM-CSF) are often administered following autologous stem cell transplantation to reduce the duration of neutropenia and limit infection-related morbidity and mortality. OBJECTIVES. (1) To determine if prophylactic myeloid growth factors (GF) administered to adult patients undergoing autologous stem cell transplantation for a hematological malignancy improve clinical outcomes post-transplant, and (2) to determine the optimal dose and schedule for the administration of GF post-transplantation. METHODS. Computerized databases were searched for reports from 1966 to March 2004. Reference lists from published reports were hand searched and published abstracts were also considered. Randomized trials comparing different GF regimens were selected by two independent assessors based on explicit inclusion and exclusion criteria; disagreement was resolved by consensus. Two independent reviewers blinded to authors, institution, journal name, and results used a validated scale to assess study quality. When possible, study results were pooled using a random effects model to obtain a pooled relative risk. RESULTS. Of 985 citations identified, 27 studies evaluating 2268 patients were included. Studies were grouped and analyzed according to their control and experimental arms: (1) early administration of growth factor (< day +3 post-transplant) compared with placebo or no growth factor (N=18 studies), (2) early administration of growth factor compared with delayed growth factor (> day +3, N=8 studies), and (3) high doses of GF (> 5ug/kg/d) compared to standard/low doses of GF (<5ug/kg/d, N=5 studies). Compared to no GF support, early administration of GF resulted in a statistically significant reduction in the median days to neutrophil engraftment (>0.5x109/L) in 14 of 15 studies (range 2–13 days). The magnitude of this benefit was diminished when only studies of higher methodologic quality and optimal transplant conditions (peripheral blood stem cells) were considered (range 2–3 days). A significant decrease in duration of hospitalization was reported in 8 of 15 studies; however no consistent benefit was observed for median days of i.v. antibiotics (3 of 10 studies), median days of fever (1 of 10 studies), or in the rate of microbiologically documented infections (RR 0.94, 95% CI 0.69–1.29). Compared to delayed administration of GF, early administration of GF was not associated with a significant difference in median duration of neutropenia any of 5 studies. Only 1 study reported a significant difference in the median duration of hospitalization and median days of i.v. antibiotics and it was of lower methodological quality. No difference in the rate of microbiologically documented infections was detected (RR 1.29, 95% CI 0.83–2.03). Compared to standard doses of GF, no study evaluating high dose GF reported a statistically significant improvement in any reported outcome but treatment was more costly owing to an increase in total GF administered. CONCLUSION. The administration of GF post-autologous stem cell transplant reduces the time to neutrophil engraftment and may reduce length of hospital stay. The effectiveness of delayed administration of standard dose GF (5 ug/kg/d) appears similar to strategies that initiate GF support immediately post-transplant or utilize high doses.

Working Toward Better Tissue Repair Therapies: Exposure of MSC to Hypoxic Conditions In Vitro Increases Levels of the Hepatocyte Growth Factor Receptor c-met, Improves Motility, and Induces Phosphorylation of the Pro-Survival Protein AKT.

Blood ◽  
2005 ◽  
Vol 106 (11) ◽  
pp. 2313-2313
Author(s):  
Ivana Rosova ◽  
Todd E. Meyerrose ◽  
Jan A. Nolta
Keyword(s):  
Stem Cells ◽  
Bone Marrow ◽  
Stem Cell ◽  
Growth Factor ◽  
Hepatocyte Growth Factor ◽  
Liver Damage ◽  
Tissue Damage ◽  
Cardiac Ischemia ◽  
Hypoxic Conditions ◽  
Hepatocyte Growth

Abstract Necrosis, apoptosis, and fibrosis are characteristics of tissue damage/injuries such as cardiac ischemia and liver damage. In most instances, a loss of blood supply due to death of endothelial cells results, creating a hypoxic environment at the damage sites. In addition, a flux of growth factors and chemokines are induced as a “rescue” signal to recruit exogenous and/or proximal stem cells into proliferation and differentiation. One such soluble factor reported to have both mitogenic and motogenic effect on stem cells for liver and cardiac regeneration is the hepatocyte growth factor (HGF), also known as “scatter factor”. Our lab has previously demonstrated that administration of HGF in vivo following human hematopoietic stem cell transplantation into an immune deficient mouse model of liver injury greatly enhances recruitment of human stem cells to sites of liver damage (Wang et al, Blood 2003). In the current studies, we addressed the role of HGF in promoting human bone marrow-derived mesenchymal stem cells (MSC) to sites of tissue damage such as liver or cardiac ischemia. In addition to exploiting the beneficial effect of HGF, we also evaluated the possible additive effect of hypoxia in stem cell regeneration based on the following hypothesis - that exposure of MSC to hypoxic conditions prior to transplantation will enhance the levels of c-met and amplify the signaling cascades downstream of HGF/c-met. To answer the question of whether MSCs have increased motility in hypoxic conditions, human bone marrow derived MSC were cultured in hypoxic (2 to 3% oxygen) vs. normoxic conditions (20–21% O2) in the presence or absence of 25ng/ml HGF, and scratch tests were performed to assess the scattering potential of MSC. There was an increase in total c-met protein, by immunohistochemical analysis, and increased migration of MSC under hypoxic conditions with HGF, as compared to normoxic conditions with HGF. Protein studies were designed to measure c-met induction/stabilization and downstream signals following ligand binding. By immunoprecipitation followed by immunoblotting with specific phosphorylation antibodies, we showed that hypoxic conditions + HGF stimulation induced a higher level of total cellular phosphotyrosine activity in MSC. Downstream of HGF/c-met, we observed an amplification of AKT phosphorylation when comparing HGF stimulation under normoxic vs. hypoxic conditions. In contrast, MAPK phosphorylation was moderately, but not significantly, different between hypoxic vs. normoxic conditions. Our data from these functional and molecular studies suggest that pre-treatment of MSC under hypoxic conditions might not only increase c-met to enhance HGF-mediated chemotactic recruitment to sites of tissue damage but may also enhance the survival of these stem cells upon arrival at the damaged site, through increasing the levels of phosphorylation of the pro-survival protein AKT.

Can Basic Fibroblast Growth Factor Pre-Treatment Enhance Mesenchymal Stem Cell Therapy in Undecorticated Posterior Spinal Fusion?

2007 ◽  
Vol 330-332 ◽  
pp. 1137-1140
Author(s):  
Chan Wai Chan ◽  
K.H.K. Wong ◽  
K.M. Lee ◽  
Ling Qin ◽  
H.Y. Yeung ◽  
...  
Keyword(s):  
Stem Cells ◽  
Bone Marrow ◽  
Mesenchymal Stem Cells ◽  
Stem Cell ◽  
Growth Factor ◽  
Spinal Fusion ◽  
Xylenol Orange ◽  
Posterior Spinal Fusion ◽  
Control Group ◽  
Fibroblast Growth

Basic fibroblast growth factor (bFGF) has been shown to maintain the osteogenicity of bone marrow derived mesenchymal stem cell (MSCs) in vitro. This study was to investigate whether bFGF with osteogenic supplements could enhance bone formation of posterior spinal fusion. Rabbit bone marrow derived mesenchymal stem cells were selected by adherence on plastic culture-ware. The MSCs were exposed to dexamethasone with (bFGF group, n=6) or without bFGF (OS group, n=6). Treated cells of two groups were seeded on β-tricalcium phosphate ceramics for one day and then implanted onto L5 and L6 transverse processes of the same animal in posterior spinal fusion without decortication. The ceramics acted as control (n=6). Three fluorochromes were injected sequentially as tetracycline at week 2, xylenol orange at week 4 and calcein at week 6. The spinal segments were harvested at week 7. The bone mineral content (BMC) and volume of transverse processes was measured by peripheral quantitative computed tomography. The specimens were underwent undecalcified histology. The mineralization process was examined by fluorescent microscopy. The BMC of transverse processes in OS group was 16% greater than bFGF and control group significantly. The volume of transverse process in OS and bFGF group was significantly greater than control group by 54% and 46% respectively. The volume of transverse processes in OS group was 6% greater than bFGF group though not statistically significant. In histology, newly formed bone grew from two processes towards each other resulting in a relatively short gap distance in OS and bFGF group while less regenerated bone was observed in the control group. At the mineralization front, calcein which was injected into animal at week 6, was predominately labeled in bFGF group. In OS group, both xylenol orange (at week 4) and calcein labeled were found. In conclusion, mesenchymal stem cells pre-exposed to bFGF were not found to give additional enhancement effect on bone formation in the posterior spinal fusion model.

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