- Open Access
Nutraceutical augmentation of circulating endothelial progenitor cells and hematopoietic stem cells in human subjects
© Mikirova et al; licensee BioMed Central Ltd. 2010
- Received: 5 February 2010
- Accepted: 8 April 2010
- Published: 8 April 2010
The medical significance of circulating endothelial or hematopoietic progenitors is becoming increasing recognized. While therapeutic augmentation of circulating progenitor cells using G-CSF has resulted in promising preclinical and early clinical data for several degenerative conditions, this approach is limited by cost and inability to perform chronic administration. Stem-Kine is a food supplement that was previously reported to augment circulating EPC in a pilot study. Here we report a trial in 18 healthy volunteers administered Stem-Kine twice daily for a 2 week period. Significant increases in circulating CD133 and CD34 cells were observed at days 1, 2, 7, and 14 subsequent to initiation of administration, which correlated with increased hematopoietic progenitors as detected by the HALO assay. Augmentation of EPC numbers in circulation was detected by KDR-1/CD34 staining and colony forming assays. These data suggest Stem-Kine supplementation may be useful as a stimulator of reparative processes associated with mobilization of hematopoietic and endothelial progenitors.
- Granulocyte Colony Stimulate Factor
- Endothelial Progenitor Cell
- Stem Cell Mobilization
- Kinase Insert Domain Receptor
Autologous bone marrow derived stem cell therapy has demonstrated benefit in early clinical trials for conditions such as critical limb ischemia [1, 2], post infarct remodeling , stroke [4, 5], and liver failure . While original mechanisms of action were believed to be associated with transdifferentiation of progenitor cells to injured tissues, more recent data supports the notion that trophic/paracrine mechanisms may be involved. In this scenario the primary therapeutic function of the administered cells is production of growth factors/anti-apoptotic factors that accelerate tissue healing [7–9]. Unfortunately, despite our more advanced mechanistic understanding of cellular therapy, its widespread implementation is hindered by need for complex cell processing facilities that are only available at limited medical institutions. A more simplistic strategy would involve administration of agents capable of enhancing endogenous stem cell activity, or alternatively mobilizing bone marrow resident stem cells to increase concentration to an area of need.
It is known that subsequent to a variety of tissue injuries, such as myocardial infarction , stroke , and long bone fractures [12, 13], endogenous stem cells are mobilized to the periphery, en route to the site of damage. The cytokines stromal derived factor (SDF-1) , vascular endothelial growth factor (VEGF) , and hepatocyte growth factor (HGF-1)  appear to act as homing signals generated by injured tissues for reparative cells. Given that stem cell mobilization appears to be associated with response to injury, one therapeutic approach has been to artificially augment mobilization subsequent to tissue damage by administration of mobilizing agents. In this manner the increased number of circulating stem cells are more available to respond to injury signals, hypothetically resulting in enhanced healing.
Granulocyte colony stimulating factor (G-CSF) and granulocyte-macrophage colony stimulating factor (GM-CSF) have been used in hematology for over two decades to mobilize donor hematopoietic stem cells [16, 17]. These mobilizers have recently been used in non-hematological clinical trials to stimulate post-injury healing processes. For example, in a trial of post acute myocardial infarct patients, administration of G-CSF for 5 days resulted in significant inhibition of pathological remodeling and improvement in ejection fraction . In the chronic injury setting, a trial of 45 patients with peripheral artery disease demonstrated improvement in vascular reactivity and walking time 12-weeks after a 2 week treatment with GM-CSF . Improvements in endothelial function have also been reported in cancer patients post G-CSF mobilization . Other studies have demonstrated the feasibility of stem cell mobilization as a possible therapy in diverse degenerative conditions such as liver failure [21, 22] and ALS .
Chronic stimulation of stem cell mobilization is not possible using agents such as G-CSF, due to cost and possible adverse effects such as thrombosis which would be enhanced after long-term use . Less invasive interventions have been reported to augment circulating stem cells such as smoking cessation or exercise [25, 26]. In the current study we investigated whether a commercially-available nutraceutical, Stem-Kine (Aidan Products, Chandler AZ), was capable of increasing the number of circulating stem cells and progenitor cells. This proprietary food supplement is produced by fermentation of a combination of green tea, astralagus, goji berry extracts, with food-derived lactobacillus Fermentum together with ellagic acid, beta 1,3 glucan and vitamin D3. In a previous study we reported preliminary data on increased circulating endothelial progenitor cell (EPC) levels subsequent to administration (Mikirova et al. Journal of Translational Medicine in press). In the current study we sought to assess kinetics of EPC and stem cell mobilization in a larger population. Augmentation of both CD133 and CD34 cells in circulation was observed, as well as KDR-1+/CD34+ EPC capable of forming endothelial colonies. In contrast to pre-treatment levels, circulating stem/EPC cells were observed to undergo an approximate 2-fold increase as a result of daily supplementation.
Study population and treatment
The study was conducted under Institutional Review Board Approval of The Center for Improvement of Human Health International, Wichita, Kansas, USA, IRB # 2009-02. Eighteen adults ages 20 -72 where recruited into the study after understanding and signing informed consent. Exclusion criteria included: systemic immune-compromised state, ongoing infection or disease conditions, and significant abnormalities in biochemistry or complete blood count panels. Subjects ceased any nutritional supplementation such as vitamins and minerals 4-5 days before trial initiation. Two 8 ml blood draws in heparinized Vacutainer tubes were collected by venipuncture before administration of Stem-Kine supplementation (day 0) and at days 1, 2, 7, and 14. Study participants were required to ingest two capsules of Stem-Kine in the morning and two in the evening for 14 days.
Phenotypic assessment of circulating stem cells
Peripheral blood mononuclear cells (PBMC) were isolated by the Ficoll-Hypaque (Fisher Scientific, Portsmouth NH) method . Briefly, blood samples were diluted two-fold with PBS and layered onto Ficoll-Hypaque in 50-ml conical tubes (Corning, Acton, MA). Each tube was centrifuged at 400 g for 30 min and the lymphocytes at the interface were collected. Cells were washed twice with RPMI 1640 medium containing 100 U/ml penicillin, 100 μg/ml streptomycin, and 2 mM L-glutamine, and subsequently resuspended in 100 ul (0.5 M cells per 100 ul) of buffer (PBS+0.5% BSA). Cells were stained with anti-CD45-FITC (BD Pharmingen), antihuman-KDR-PE, anti-CD34-PE (BD Pharminogen), CD133/AC133-PE (Miltenyi Biotec), or isotype controls recommended by manufacturer. Specifically, 10 ul of antibody was added per 100 ul of resuspended cells and refrigerated in the dark for 15 min (4-8) C. Cells were washed in 2 ml of PBS with 0.5% BSA and resuspended in 100 ul of buffer for analysis. Flow cytometry was performed using a Cell Lab Quant SC system (Beckman Coulter) equipped with 22 mW argon laser tuned at 488 nm, with the total number of cells counted cells being 30,000 per sample. The percentage of CD133 and CD34 positive cells was calculated based on the measured number of leukocytes (CD45-positive cells).
Quantification of EPC based on colony forming ability
EPC cultures were performed using a modification of the previously described method [28–31]. Briefly, PBMC were plated on 24-well fibronectin-coated plates in Endocult liquid medium, comprised of EndoCult basal Medium and EndoCult supplement with growth factors and 2% fetal calf serum (Stem Cell Technologies, Vancouver, Canada). Cells were plated at a concentration 1 million cells per well for 5 days. For each subject colonies were plated in triplicate. Colonies represented clusters of more than 50 cells circumscribed by spindle shaped cells and were counted by microscope. As the number of colonies depends on the number of plated cells, normalization of colony number based amount of cells plated was performed twice. The coefficient for normalization was calculated from the level of ATP for the same amount of plated cells after 5 days of plating in medium without growth factors.
HALO hematopoietic progenitor assay
The H ematopoietic/Hemotoxicity A ssay via L uminescent O utput (HALO, HemoGenix, Inc) assay was performed according to the manufacturer's instructions . Briefly, PBMC were plated in a methylcellulose media (HemoGenix) with and without the addition of a growth factor cocktail consisting of erythropoietin (EPO, 3 U/mL), granulocyte-macrophage-colony-stimulating factor (GM-CSF, 20 ng/mL), granulocyte colony-stimulating factor (G-CSF, 20 ng/mL), interleukin-3 (IL-3, 10 ng/mL), interleukin-6 (IL-6, 20 ng/mL), stem cell factor (SCF, 50 ng/mL), thrombopoietin (TPO, 50 ng/mL), and Flt-3 ligand (10 ng/mL). Cells were plated at a concentration of 20000 cells per well in 96 well plates. After 5 days of culture, level of cellular ATP was quantified by bio-luminescence. The ratio of average values of ATP in growth factor stimulated and not stimulated cells was calculated and compared for different periods before and after intervention.
Differences between the groups were assessed using the non-parametric Wilcoxon rank test and P < 0.05 was considered to indicate statistical significance.
Stem-Kine mobilizes CD34 and CD133 Cells
Analysis of the number of the progenitor cells in circulation by HALO assay
Stem-Kine augments circulation of cells with EPC phenotype
Stem-Kine increases circulating cells with EPC activity
Hematopoietic stem cells at various stages of differentiation are localized in the bone-marrow. At a basal rate low levels of stem/progenitor cells are released from their niche and circulate in the peripheral blood . Initially, upregulation of peripheral blood hematopoietic stem cell numbers was believed to be limited to post-bone marrow injury conditions , subsequent studies have expanded this finding to situations of inflammation , and peripheral tissue injury [45–47]. Hematopoietic stem cells are being increasingly recognized as having diverse non-hematopoietic functions including production of angiogenic cytokines , and acting as an "innate" immune cell capable of rapidly differentiating into dendritic cells for protection of the host against infections . Circulating EPC are derived from the same lineage as hematopoietic cells , and are believed to play a role in replenishing the vasculature [51–53]. Numerous conditions including Alzheimer's Disease , migraine headaches , erectile dysfunction , diabetes, and peripheral vascular disease are associated with decreases in circulating EPC, possibly as a result of chronic inflammatory mediators associated with these conditions [57, 58]. In contrast, acute injury such as myocardial infarction [59, 60] and stroke , are associated with upregulated levels of these cells. Given the possibility that both hematopoietic stem cells and EPC may serve as endogenous "repair cells", we sought to assess a relatively non-invasive means of modulating these cells.
Stem-Kine is a commercially available food supplement whose intake has been associated with a variety of anecdotal reports of health improvement such as increased energy levels, enhanced skin quality, resistance to infection, and accelerated post-infection recovery. We found that administration of Stem-Kine over a 2-week course was well tolerated with no adverse effects reported. Supplementation was associated with a peak increase of approximately 53% in the number of CD34 expressing cells and and a 90% increase in CD133 cells in circulation. Furthermore, a significant augmentation of cells possessing hematopoietic colony forming activity was found in PBMC by the HALO assay. The levels of mobilization associated with Stem-Kine administration are closer to conditions that can be maintained over long term use, which is not possible with currently available mobilizers. For example, G-CSF administration at a conventionally used dose, 12 micrograms/kg for 6 days, results in a 58-fold increase in granulocytic progenitors and 24-fold increase in erythroid progenitors , which approximately correlated with CD34 counts . Maintaining such extreme levels of mobilization over a long term increases the risk of extramedullary hematopoiesis , bone marrow depletion , and thrombosis as a result of chronic leukocytosis . Indeed current indications for G-CSF recommend its use be limited to no more than 7 days for purposes of mobilization . The recently approved drug AMD-3100 stimulates CD34 and CFU-GM mobilization approximately half of values obtained for G-CSF alone, however has been demonstrated to synergize with G-CSF . The rapid onset and extent of mobilization limits chronic administration. As with other mobilizing agents, Stem-Kine peripheralization of CD34 and CD133 cells started to drop on day 14 of administration. This may be a physiological response towards maintaining a constant level of circulating progenitor cells. Indeed it may be possible that Stem-Kine could be beneficial in conditions associated with reduced progenitor cells such as diabetes or in smokers which possess lower baseline values as compared to controls [25, 26, 57, 58].
While we correlated an increase in hematopoietic colonies with Stem-Kine induced upregulation of peripheral blood CD34 and CD133 cells, given that these markers are also found on EPC , we evaluated the possibility that circulating EPC numbers were also increased. We observed maximal increases (almost doubling) of CD34+ KDR+ cells in PBMC occurring at day 7 of supplementation, whereas peak CFU-E activity occurred at day 2. The reason for this discrepancy is not known, but potentially may be related to existence of various subsets of cells with EPC potential residing outside of the CD34+ KDR+ fraction. Further studies are required to elucidate functional importance of the variable kinetics of mobilization, as well as possible differences on long-term versus short-term circulating EPC.
The mechanism of Stem-Kine mediated mobilization remains unknown. One possibility is that a temporary disruption of the SDF-1a/CXCR4 axis is occurring, in a similar manner to mobilization induced by G-CSF or cyclophosphamide . Not mutually exclusive is the possibility that Stem-Kine is activating bone marrow resident macrophages, elaborating cytokines associated with mobilization . We are favoring this possibility based on agents that induce mobilization in the relative potency range associated with Stem-Kine. For example, specific molecular weight ranges of hyaluronic acid have been demonstrated to induce mild mobilization [70, 71], an effect that is associated with bone marrow macrophage production of IL-1 and IL-6 . Peptidoglycan components which are found in Stem-Kine are known to activate macrophages and stimulate production of IL-6 .
To our knowledge, this is the first study demonstrating profound mobilization effect with possible clinical significance by a food supplement-based approach. The nutritional supplement StemEnhance, is an extract of the cyanobacteria Aphanizomenon flos-aquae . Jensen et al which demonstrated a 25% increase in circulating CD34+ cells, which peaked at 60 minutes-post administration and subsided at 120 minutes . Another nutraceutical product, Nutra-Stem, is composed of a combination of blueberries, green tea extract, carnosine, and vitamin D3. In vitro activity on proliferation of human bone marrow cells was assessed, in which a 60% enhancement of growth was reported . Bone marrow cells from mice supplemented with Nutra-Stem were protected from in vitro exposure to hydrogen peroxide at up to approximately 40% . These data suggest the possibility of nutritional modulation of stem cell compartments, but do not provide results on mobilization. Further research is required to assess physiological effects in humans.
In conclusion, the current study suggests feasibility of significant mobilization of cells expressing hematopoietic stem cell and EPC markers and properties. The area of nutritional modulation of the stem cell compartment offers significant benefit in treatment of a wide variety of degenerative diseases. However given commercial pressures associated with this largely unregulated field, we propose detailed scientific investigations must be made before disease-associated claims are made by the scientific community.
This study was supported in part by Allan P Markin, The Aidan Foundation, and the Center For The Improvement Of Human Functioning International.
- Kawamoto A, Katayama M, Handa N: Intramuscular transplantation of G-CSF-mobilized CD34(+) cells in patients with critical limb ischemia: a phase I/IIa, multicenter, single-blinded, dose-escalation clinical trial. Stem Cells. 2009, 27 (11): 2857-64. 10.1002/stem.207.PubMedGoogle Scholar
- Keller LH: Bone marrow-derived aldehyde dehydrogenase-bright stem and progenitor cells for ischemic repair. Congest Heart Fail. 2009, 15 (4): 202-6. 10.1111/j.1751-7133.2009.00101.x.PubMedGoogle Scholar
- Singh S, Arora R, Handa K, Khraisat A, Nagajothi N, Molnar J, Khosla S: Stem cells improve left ventricular function in acute myocardial infarction. Clin Cardiol. 2009, 32 (4): 176-80. 10.1002/clc.20470.PubMedGoogle Scholar
- Fischer-Rasokat U, Assmus B, Seeger FH: A pilot trial to assess potential effects of selective intracoronary bone marrow-derived progenitor cell infusion in patients with nonischemic dilated cardiomyopathy: final 1-year results of the transplantation of progenitor cells and functional regeneration enhancement pilot trial in patients with nonischemic dilated cardiomyopathy. Circ Heart Fail. 2009, 2 (5): 417-23. 10.1161/CIRCHEARTFAILURE.109.855023.PubMedGoogle Scholar
- Suarez-Monteagudo C, Hernandez-Ramirez P, Alvarez-Gonzalez L: Autologous bone marrow stem cell neurotransplantation in stroke patients. An open study. Restor Neurol Neurosci. 2009, 27 (3): 151-61.PubMedGoogle Scholar
- Pai M, Zacharoulis D, Milicevic MN: Autologous infusion of expanded mobilized adult bone marrow-derived CD34+ cells into patients with alcoholic liver cirrhosis. Am J Gastroenterol. 2008, 103 (8): 1952-8. 10.1111/j.1572-0241.2008.01993.x.PubMedGoogle Scholar
- Caplan AI, Dennis JE: Mesenchymal stem cells as trophic mediators. J Cell Biochem. 2006, 98 (5): 1076-84. 10.1002/jcb.20886.PubMedGoogle Scholar
- Ventura C, Cavallini C, Bianchi F, Cantoni S: Stem cells and cardiovascular repair: a role for natural and synthetic molecules harboring differentiating and paracrine logics. Cardiovasc Hematol Agents Med Chem. 2008, 6 (1): 60-8. 10.2174/187152508783329975.PubMedGoogle Scholar
- Shabbir A, Zisa D, Suzuki G, Lee T: Heart failure therapy mediated by the trophic activities of bone marrow mesenchymal stem cells: a noninvasive therapeutic regimen. Am J Physiol Heart Circ Physiol. 2009, 296 (6): H1888-97. 10.1152/ajpheart.00186.2009.PubMedPubMed CentralGoogle Scholar
- Brehm M, Ebner P, Picard F, Urbien R, Turan G, Strauer BE: Enhanced mobilization of CD34(+) progenitor cells expressing cell adhesion molecules in patients with STEMI. Clin Res Cardiol. 2009, 98 (8): 477-86. 10.1007/s00392-009-0021-5.PubMedGoogle Scholar
- Dunac A, Frelin C, Popolo-Blondeau M, Chatel M, Mahagne MH, Philip PJ: Neurological and functional recovery in human stroke are associated with peripheral blood CD34+ cell mobilization. J Neurol. 2007, 254 (3): 327-32. 10.1007/s00415-006-0362-1.PubMedGoogle Scholar
- Lee DY, Cho TJ, Kim JA, Lee HR, Yoo WJ, Chung CY, Choi IH: Mobilization of endothelial progenitor cells in fracture healing and distraction osteogenesis. Bone. 2008, 42 (5): 932-41. 10.1016/j.bone.2008.01.007.PubMedGoogle Scholar
- Matsumoto T, Mifune Y, Kawamoto A: Fracture induced mobilization and incorporation of bone marrow-derived endothelial progenitor cells for bone healing. J Cell Physiol. 2008, 215 (1): 234-42. 10.1002/jcp.21309.PubMedGoogle Scholar
- Das R, Jahr H, van Osch G, Farrell E: The role of hypoxia in MSCs: Considerations for regenerative medicine approaches. Tissue Eng Part B Rev. 2009, 42 (5): 234-42.Google Scholar
- Vandervelde S, van Luyn MJ, Tio RA, Harmsen MC: Signaling factors in stem cell-mediated repair of infarcted myocardium. J Mol Cell Cardiol. 2005, 39 (2): 363-76. 10.1016/j.yjmcc.2005.05.012.PubMedGoogle Scholar
- Mohle R, Kanz L: Hematopoietic growth factors for hematopoietic stem cell mobilization and expansion. Semin Hematol. 2007, 44 (3): 193-202. 10.1053/j.seminhematol.2007.04.006.PubMedGoogle Scholar
- Gianni AM, Siena S, Bregni M, Tarella C, Stern AC, Pileri A, Bonadonna G: Granulocyte-macrophage colony-stimulating factor to harvest circulating haemopoietic stem cells for autotransplantation. Lancet. 1989, 2 (8663): 580-5. 10.1016/S0140-6736(89)90711-3.PubMedGoogle Scholar
- Leone AM, Galiuto L, Garramone B: Usefulness of granulocyte colony-stimulating factor in patients with a large anterior wall acute myocardial infarction to prevent left ventricular remodeling (the rigenera study). Am J Cardiol. 2007, 100 (3): 397-403. 10.1016/j.amjcard.2007.03.036.PubMedGoogle Scholar
- Subramaniyam V, Waller EK, Murrow JR: Bone marrow mobilization with granulocyte macrophage colony-stimulating factor improves endothelial dysfunction and exercise capacity in patients with peripheral arterial disease. Am Heart J. 2009, 158 (1): 53-60. 10.1016/j.ahj.2009.04.014. e1.PubMedGoogle Scholar
- Ikonomidis I, Papadimitriou C, Vamvakou G: Treatment with granulocyte colony stimulating factor is associated with improvement in endothelial function. Growth Factors. 2008, 26 (3): 117-24. 10.1080/08977190802090614.PubMedGoogle Scholar
- Spahr L, Lambert JF, Rubbia-Brandt L, Chalandon Y, Frossard JL, Giostra E, Hadengue A: Granulocyte-colony stimulating factor induces proliferation of hepatic progenitors in alcoholic steatohepatitis: a randomized trial. Hepatology. 2008, 48 (1): 221-9. 10.1002/hep.22317.PubMedGoogle Scholar
- Di Campli C, Zocco MA, Saulnier N: Safety and efficacy profile of G-CSF therapy in patients with acute on chronic liver failure. Dig Liver Dis. 2007, 39 (12): 1071-6. 10.1016/j.dld.2007.08.006.PubMedGoogle Scholar
- Cashman N, Tan LY, Krieger C: Pilot study of granulocyte colony stimulating factor (G-CSF)-mobilized peripheral blood stem cells in amyotrophic lateral sclerosis (ALS). Muscle Nerve. 2008, 37 (5): 620-5. 10.1002/mus.20951.PubMedGoogle Scholar
- Nadir Y, Hoffman R, Brenner B: Drug-related thrombosis in hematologic malignancies. Rev Clin Exp Hematol. 2004, 8 (1): E4-PubMedGoogle Scholar
- Kondo T, Hayashi M, Takeshita K, Numaguchi Y, Kobayashi K, Iino S, Inden Y, Murohara T: Smoking cessation rapidly increases circulating progenitor cells in peripheral blood in chronic smokers. Arterioscler Thromb Vasc Biol. 2004, 24 (8): 1442-7. 10.1161/01.ATV.0000135655.52088.c5.PubMedGoogle Scholar
- Mobius-Winkler S, Hilberg T, Menzel K, Golla E, Burman A, Schuler G, Adams V: Time-dependent mobilization of circulating progenitor cells during strenuous exercise in healthy individuals. J Appl Physiol. 2009, 107 (6): 1943-50. 10.1152/japplphysiol.00532.2009.PubMedGoogle Scholar
- Kmieciak M, Gowda M, Graham L, Godder K, Bear HD, Marincola FM, Manjili MH: Human T cells express CD25 and Foxp3 upon activation and exhibit effector/memory phenotypes without any regulatory/suppressor function. J Transl Med. 2009, 7: 89-10.1186/1479-5876-7-89.PubMedPubMed CentralGoogle Scholar
- Hill JMZG, Halcox JP, Schenke WH, Wacliwiw MA, Quyyumi AA, Finkel T: Circulating endothelial progenitor cells, vascular function and cardiovascular risk. M Engl J Med. 2003, 348: 593-600. 10.1056/NEJMoa022287.Google Scholar
- Vasa MFS, Aicher A, Adler K, Urbich C, martin H, Zeiher AM, Dimmeler S: Number and migratory activity of circulating endothelial cells inversely correlate with risk factors for coronary heart disease. Circ Res. 2001, 89: e1-e7. 10.1161/hh1301.093953.PubMedGoogle Scholar
- Werner NK, Osiol S, Schiegl T, Ahlers P, Walenta K, Link A, Bohm M, Nickenig G: Circulating endothelial progenitor cells and cardio-vascular outcomes. N Engl J Med. 1007, 353: 999-2005. 10.1056/NEJMoa043814.Google Scholar
- Rehman JLJ, Parvathaneni L, Karlsson G, Panchal VR, Temm CJ, Mahenthiran J, March KL: Exercise acutely increases circulating endothelial progenitor cells and monocyte-/macrophage-derived angiogenic cells. J Am Coll Cardiol. 2004, 43: 2314-2318. 10.1016/j.jacc.2004.02.049.PubMedGoogle Scholar
- Rich IN: In vitro hematotoxicity testing in drug development: a review of past, present and future applications. Curr Opin Drug Discov Devel. 2003, 6 (1): 100-9.PubMedGoogle Scholar
- Charrier S, Boiret N, Fouassier M: Normal human bone marrow CD34(+)CD133(+) cells contain primitive cells able to produce different categories of colony-forming unit megakaryocytes in vitro. Exp Hematol. 2002, 30 (9): 1051-60. 10.1016/S0301-472X(02)00882-2.PubMedGoogle Scholar
- Handgretinger R, Gordon PR, Leimig T, Chen X, Buhring HJ, Niethammer D, Kuci S: Biology and plasticity of CD133+ hematopoietic stem cells. Ann N Y Acad Sci. 2003, 996: 141-51. 10.1111/j.1749-6632.2003.tb03242.x.PubMedGoogle Scholar
- Rich IN: HKVadoappfhuambc-fpaTS. 2005, 87: 427-441.Google Scholar
- Crouch SPMKR, Slater KJ, Fletcher J: The use of ATP bioluminescence as a measure of cell proliferation and cytotoxicity. L immunol meth. 2000, 160: 81-88. 10.1016/0022-1759(93)90011-U.Google Scholar
- Mauro E, Rigolin GM, Fraulini C, Sofritti O, Ciccone M, De Angeli C, Castoldi G, Cuneo A: Mobilization of endothelial progenitor cells in patients with hematological malignancies after treatment with filgrastim and chemotherapy for autologous transplantation. Eur J Haematol. 2007, 78 (5): 374-80. 10.1111/j.1600-0609.2007.00831.x.PubMedGoogle Scholar
- Kolonin MG, Simmons PJ: Combinatorial stem cell mobilization. Nat Biotechnol. 2009, 27 (3): 252-3. 10.1038/nbt0309-252.PubMedGoogle Scholar
- Pitchford SC, Furze RC, Jones CP, Wengner AM, Rankin SM: Differential mobilization of subsets of progenitor cells from the bone marrow. Cell Stem Cell. 2009, 4 (1): 62-72. 10.1016/j.stem.2008.10.017.PubMedGoogle Scholar
- Westerweel PE, Visseren FL, Hajer GR: Endothelial progenitor cell levels in obese men with the metabolic syndrome and the effect of simvastatin monotherapy vs. simvastatin/ezetimibe combination therapy. Eur Heart J. 2008, 29 (22): 2808-17. 10.1093/eurheartj/ehn431.PubMedGoogle Scholar
- Jie KE, Goossens MH, van Oostrom O, Lilien MR, Verhaar MC: Circulating endothelial progenitor cell levels are higher during childhood than in adult life. Atherosclerosis. 2009, 202 (2): 345-7. 10.1016/j.atherosclerosis.2008.05.012.PubMedGoogle Scholar
- Barnes DW, Loutit JF: Haemopoietic stem cells in the peripheral blood. Lancet. 1967, 2 (7526): 1138-41. 10.1016/S0140-6736(67)90636-8.PubMedGoogle Scholar
- Fried W, Johnson C: The effect of cyclophosphamide on hematopoietic stem cells. Radiat Res. 1968, 36 (3): 521-7. 10.2307/3572585.PubMedGoogle Scholar
- Vos O, Buurman WA, Ploemacher RE: Mobilization of haemopoietic stem cells (CFU) into the peripheral blood of the mouse; effects of endotoxin and other compounds. Cell Tissue Kinet. 1972, 5 (6): 467-79.PubMedGoogle Scholar
- Taguchi A, Nakagomi N, Matsuyama T: Circulating CD34-positive cells have prognostic value for neurologic function in patients with past cerebral infarction. J Cereb Blood Flow Metab. 2009, 29 (1): 34-8. 10.1038/jcbfm.2008.92.PubMedGoogle Scholar
- Turan RG, Brehm M, Koestering M: Factors influencing spontaneous mobilization of CD34+ and CD133+ progenitor cells after myocardial infarction. Eur J Clin Invest. 2007, 37 (11): 842-51. 10.1111/j.1365-2362.2007.01876.x.PubMedGoogle Scholar
- Kissel CK, Lehmann R, Assmus B: Selective functional exhaustion of hematopoietic progenitor cells in the bone marrow of patients with postinfarction heart failure. J Am Coll Cardiol. 2007, 49 (24): 2341-9. 10.1016/j.jacc.2007.01.095.PubMedGoogle Scholar
- Strate van der BW, Popa ER, Schipper M, Brouwer LA, Hendriks M, Harmsen MC, van Luyn MJ: Circulating human CD34+ progenitor cells modulate neovascularization and inflammation in a nude mouse model. J Mol Cell Cardiol. 2007, 42 (6): 1086-97. 10.1016/j.yjmcc.2007.03.907.PubMedGoogle Scholar
- Massberg S, Schaerli P, Knezevic-Maramica I: Immunosurveillance by hematopoietic progenitor cells trafficking through blood, lymph, and peripheral tissues. Cell. 2007, 131 (5): 994-1008. 10.1016/j.cell.2007.09.047.PubMedPubMed CentralGoogle Scholar
- Basak GW, Yasukawa S, Alfaro A, Halligan S, Srivastava AS, Min WP, Minev B, Carrier E: Human embryonic stem cells hemangioblast express HLA-antigens. J Transl Med. 2009, 7: 27-10.1186/1479-5876-7-27.PubMedPubMed CentralGoogle Scholar
- Foteinos G, Hu Y, Xiao Q, Metzler B, Xu Q: Rapid endothelial turnover in atherosclerosis-prone areas coincides with stem cell repair in apolipoprotein E-deficient mice. Circulation. 2008, 117 (14): 1856-63. 10.1161/CIRCULATIONAHA.107.746008.PubMedGoogle Scholar
- Werner N, Junk S, Laufs U, Link A, Walenta K, Bohm M, Nickenig G: Intravenous transfusion of endothelial progenitor cells reduces neointima formation after vascular injury. Circ Res. 2003, 93 (2): e17-24. 10.1161/01.RES.0000083812.30141.74.PubMedGoogle Scholar
- Wassmann S, Werner N, Czech T, Nickenig G: Improvement of endothelial function by systemic transfusion of vascular progenitor cells. Circ Res. 2006, 99 (8): e74-83. 10.1161/01.RES.0000246095.90247.d4.PubMedGoogle Scholar
- Lee ST, Chu K, Jung KH: Reduced circulating angiogenic cells in Alzheimer disease. Neurology. 2009, 72 (21): 1858-63. 10.1212/WNL.0b013e3181a711f4.PubMedGoogle Scholar
- Lee ST, Chu K, Jung KH: Decreased number and function of endothelial progenitor cells in patients with migraine. Neurology. 2008, 70 (17): 1510-7. 10.1212/01.wnl.0000294329.93565.94.PubMedGoogle Scholar
- Esposito K, Ciotola M, Maiorino MI: Circulating CD34+ KDR+ endothelial progenitor cells correlate with erectile function and endothelial function in overweight men. J Sex Med. 2009, 6 (1): 107-14. 10.1111/j.1743-6109.2008.01042.x.PubMedGoogle Scholar
- Rodriguez-Ayala E, Yao Q, Holmen C, Lindholm B, Sumitran-Holgersson S, Stenvinkel P: Imbalance between detached circulating endothelial cells and endothelial progenitor cells in chronic kidney disease. Blood Purif. 2006, 24 (2): 196-202. 10.1159/000090519.PubMedGoogle Scholar
- Verma S, Kuliszewski MA, Li SH: C-reactive protein attenuates endothelial progenitor cell survival, differentiation, and function: further evidence of a mechanistic link between C-reactive protein and cardiovascular disease. Circulation. 2004, 109 (17): 2058-67. 10.1161/01.CIR.0000127577.63323.24.PubMedGoogle Scholar
- Xin Z, Meng W, Ya-Ping H, Wei Z: Different biological properties of circulating and bone marrow endothelial progenitor cells in acute myocardial infarction rats. Thorac Cardiovasc Surg. 2008, 56 (8): 441-8. 10.1055/s-2008-1038879.PubMedGoogle Scholar
- Wojakowski W, Tendera M: Mobilization of bone marrow-derived progenitor cells in acute coronary syndromes. Folia Histochem Cytobiol. 2005, 43 (4): 229-32.PubMedGoogle Scholar
- Sobrino T, Hurtado O, Moro MA: The increase of circulating endothelial progenitor cells after acute ischemic stroke is associated with good outcome. Stroke. 2007, 38 (10): 2759-64. 10.1161/STROKEAHA.107.484386.PubMedGoogle Scholar
- Sheridan WP, Begley CG, Juttner CA: Effect of peripheral-blood progenitor cells mobilised by filgrastim (G-CSF) on platelet recovery after high-dose chemotherapy. Lancet. 1992, 339 (8794): 640-4. 10.1016/0140-6736(92)90795-5.PubMedGoogle Scholar
- Matsunaga T, Sakamaki S, Kohgo Y, Ohi S, Hirayama Y, Niitsu Y: Recombinant human granulocyte colony-stimulating factor can mobilize sufficient amounts of peripheral blood stem cells in healthy volunteers for allogeneic transplantation. Bone Marrow Transplant. 1993, 11 (2): 103-8.PubMedGoogle Scholar
- Dagdas S, Ozet G, Alanoglu G, Ayli M, Gokmen Akoz A, Erekul S: Unusual extramedullary hematopoiesis in a patient receiving granulocyte colony-stimulating factor. Acta Haematol. 2006, 116 (3): 198-202. 10.1159/000094681.PubMedGoogle Scholar
- Majolino I, Cavallaro AM, Scime R: Peripheral blood stem cells for allogeneic transplantation. Bone Marrow Transplant. 1996, 18 (Suppl 2): 171-4.PubMedGoogle Scholar
- Neupogen (Filgrastim). [http://www.neupogen.com/pdf/Neupogen_PI.pdf]
- Broxmeyer HE, Orschell CM, Clapp DW: Rapid mobilization of murine and human hematopoietic stem and progenitor cells with AMD a CXCR4 antagonist. J Exp Med. 3100, 201 (8): 1307-18. 10.1084/jem.20041385.Google Scholar
- Levesque JPHJ, Takamatsu Y, Simmons PJ, Bendall LJ: Disruption of the CXCR4/CXCL12 chemotactic interaction during hematopoietic stem cell mobilization induced by G-CSF or cyclophosphamide. J Clin Inves. 2003, 111: 187-196.Google Scholar
- Cavaillon JMH-CN: Signals involved in interleukin 1 synthesis and release by lipopolysacchride-stimulated monocyte/macrophages. Cytokines. 1990, 2: 313-10.1016/1043-4666(90)90061-W.Google Scholar
- Minguell JJ: Is hyaluronic acid the "organizer" of the extracellular matrix in marrow stroma?. Exp Hematol. 1993, 21 (1): 7-8.PubMedGoogle Scholar
- Matrosova VY, Orlovskaya IA, Serobyan N, Khaldoyanidi SK: Hyaluronic acid facilitates the recovery of hematopoiesis following 5-fluorouracil administration. Stem Cells. 2004, 22 (4): 544-55. 10.1634/stemcells.22-4-544.PubMedGoogle Scholar
- Hiro D, Ito A, Matsuta K, Mori Y: Hyaluronic acid is an endogenous inducer of interleukin-1 production by human monocytes and rabbit macrophages. Biochem Biophys Res Commun. 1986, 140 (2): 715-22. 10.1016/0006-291X(86)90790-4.PubMedGoogle Scholar
- Riordan : US patent # 6. 940-Google Scholar
- StemTech International Inc. [http://www.stemtechbiz.com]
- Jensen GS, Hart AN, Zaske LA, Drapeau C, Gupta N, Schaeffer DJ, Cruickshank JA: Mobilization of human CD34+ CD133+ and CD34+ CD133(-) stem cells in vivo by consumption of an extract from Aphanizomenon flos-aquae--related to modulation of CXCR4 expression by an L-selectin ligand?. Cardiovasc Revasc Med. 2007, 8 (3): 189-202. 10.1016/j.carrev.2007.03.004.PubMedGoogle Scholar
- Bickford PC, Tan J, Shytle RD, Sanberg CD, El-Badri N, Sanberg PR: Nutraceuticals synergistically promote proliferation of human stem cells. Stem Cells Dev. 2006, 15 (1): 118-23. 10.1089/scd.2006.15.118.PubMedGoogle Scholar
- Shytle RD, Ehrhart J, Tan J, Vila J, Cole M, Sanberg CD, Sanberg PR, Bickford PC: Oxidative stress of neural, hematopoietic, and stem cells: protection by natural compounds. Rejuvenation Res. 2007, 10 (2): 173-8. 10.1089/rej.2006.0515.PubMedGoogle Scholar
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