Robert C Robbins

Stanford Medicine, Stanford, California, United States

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Publications (469)2637.3 Total impact

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    ABSTRACT: Different tissue-engineering approaches have been developed to induce and promote cardiac regeneration; however, the impact of the immune system and its responses to the various scaffold components of the engineered grafts remains unclear. Fibrin-based engineered heart tissue (EHT) was generated from neonatal Lewis (Lew) rat heart cells and transplanted onto the left ventricular surface of three different rat strains: syngeneic Lew, allogeneic Brown Norway, and immunodeficient Rowett Nude rats. Interferon spot frequency assay results showed similar degrees of systemic immune activation in the syngeneic and allogeneic groups, whereas no systemic immune response was detectable in the immunodeficient group (p < .001 vs. syngeneic and allogeneic). Histological analysis revealed much higher local infiltration of CD3- and CD68-positive cells in syngeneic and allogeneic rats than in immunodeficient animals. Enzyme-linked immunospot and immunofluorescence experiments revealed matrix-directed TH1-based rejection in syngeneic recipients without collateral impairment of heart cell survival. Bioluminescence imaging was used for in vivo longitudinal monitoring of transplanted luciferase-positive EHT constructs. Survival was documented in syngeneic and immunodeficient recipients for a period of up to 110 days after transplant, whereas in the allogeneic setting, graft survival was limited to only 14 ± 1 days. EHT strategies using autologous cells are promising approaches for cardiac repair applications. Although fibrin-based scaffold components elicited an immune response in our studies, syngeneic cells carried in the EHT were relatively unaffected. ©AlphaMed Press.
    STEM CELLS TRANSLATIONAL MEDICINE 05/2015; 4(6). DOI:10.5966/sctm.2013-0202 · 3.60 Impact Factor
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    ABSTRACT: Valvular and vascular calcification are common causes of cardiovascular morbidity and mortality. Developing effective treatments requires understanding the molecular underpinnings of these processes. Shear stress is thought to play a role in inhibiting calcification. Furthermore, NOTCH1 regulates vascular and valvular endothelium, and human mutations in NOTCH1 can cause calcific aortic valve disease. Here, we determined the genome-wide impact of altering shear stress and NOTCH signaling on aortic valve endothelium. mRNA-sequencing of human aortic valve endothelial cells (HAVECs) with or without knockdown of NOTCH1, in the presence or absence of shear stress, revealed NOTCH1-dependency of the atherosclerosis-related gene connexin 40 (GJA5), and numerous repressors of endochondral ossification. Among these, Matrix GLA Protein (MGP) is highly expressed in aortic valve and vasculature, and inhibits soft tissue calcification by sequestering bone morphogenetic proteins (BMPs). Altering NOTCH1 levels affected MGP mRNA and protein in HAVECs. Furthermore, shear stress activated NOTCH signaling and MGP in a NOTCH1-dependent manner. NOTCH1 positively regulated endothelial MGP in vivo through specific binding motifs upstream of MGP. Our studies suggest that shear stress activates NOTCH1 in primary human aortic valve endothelial cells leading to downregulation of osteoblast-like gene networks that play a role in tissue calcification. Copyright © 2015. Published by Elsevier Ltd.
    Journal of Molecular and Cellular Cardiology 04/2015; 7. DOI:10.1016/j.yjmcc.2015.04.006 · 5.22 Impact Factor
  • The Journal of Heart and Lung Transplantation 04/2015; 34(4):S39. DOI:10.1016/j.healun.2015.01.092 · 5.61 Impact Factor
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    ABSTRACT: The generation of pluripotent stem cells by somatic cell nuclear transfer (SCNT) has recently been achieved in human cells and sparked new interest in this technology. The authors reporting this methodical breakthrough speculated that SCNT would allow the creation of patient-matched embryonic stem cells, even in patients with hereditary mitochondrial diseases. However, herein we show that mismatched mitochondria in nuclear-transfer-derived embryonic stem cells (NT-ESCs) possess alloantigenicity and are subject to immune rejection. In a murine transplantation setup, we demonstrate that allogeneic mitochondria in NT-ESCs, which are nucleus-identical to the recipient, may trigger an adaptive alloimmune response that impairs the survival of NT-ESC grafts. The immune response is adaptive, directed against mitochondrial content, and amenable for tolerance induction. Mitochondrial alloantigenicity should therefore be considered when developing therapeutic SCNT-based strategies. Copyright © 2015 Elsevier Inc. All rights reserved.
    Cell Stem Cell 11/2014; DOI:10.1016/j.stem.2014.11.003 · 22.15 Impact Factor
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    ABSTRACT: Surgical myectomy and alcohol septal ablation (ASA) aim to decrease left ventricular outflow tract (LVOT) gradient in hypertrophic cardiomyopathy (HCM). Outcome of myectomy beyond 10 years has rarely been described. We describe 20 years of follow-up of surgical myectomy and 5 years of follow-up for ASA performed for obstructive HCM.
    Journal of Cardiology 09/2014; DOI:10.1016/j.jjcc.2014.08.010 · 2.57 Impact Factor
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    ABSTRACT: Despite the introduction of antiproliferative drug-eluting stents, coronary heart disease remains the leading cause of death in the United States. In-stent restenosis and bypass graft failure are characterized by excessive smooth muscle cell (SMC) proliferation and concomitant myointima formation with luminal obliteration. Here we show that during the development of myointimal hyperplasia in human arteries, SMCs show hyperpolarization of their mitochondrial membrane potential (ΔΨm) and acquire a temporary state with a high proliferative rate and resistance to apoptosis. Pyruvate dehydrogenase kinase isoform 2 (PDK2) was identified as a key regulatory protein, and its activation proved necessary for relevant myointima formation. Pharmacologic PDK2 blockade with dichloroacetate or lentiviral PDK2 knockdown prevented ΔΨm hyperpolarization, facilitated apoptosis and reduced myointima formation in injured human mammary and coronary arteries, rat aortas, rabbit iliac arteries and swine (pig) coronary arteries. In contrast to several commonly used antiproliferative drugs, dichloroacetate did not prevent vessel re-endothelialization. Targeting myointimal ΔΨm and alleviating apoptosis resistance is a novel strategy for the prevention of proliferative vascular diseases.
    Nature 04/2014; 509(7502). DOI:10.1038/nature13232 · 42.35 Impact Factor
  • The Journal of Heart and Lung Transplantation 04/2014; 33(4):S54-S55. DOI:10.1016/j.healun.2014.01.179 · 5.61 Impact Factor
  • The Journal of Heart and Lung Transplantation 04/2014; 33(4):S228. DOI:10.1016/j.healun.2014.01.592 · 5.61 Impact Factor
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    ABSTRACT: Various in vivo laboratory rodent models for the induction of artery stenosis have been established to mimic diseases that include arterial plaque formation and stenosis, as observed for example in ischemic heart disease. Two highly reproducible mouse models - both resulting in artery stenosis but each underlying a different pathway of development - are introduced here. The models represent the two most common causes of artery stenosis; namely one mouse model for each myointimal hyperplasia, and atherosclerosis are shown. To induce myointimal hyperplasia, a balloon catheter injury of the abdominal aorta is performed. For the development of atherosclerotic plaque, the ApoE -/- mouse model in combination with western fatty diet is used. Different model-adapted options for the measurement and evaluation of the results are named and described in this manuscript. The introduction and comparison of these two models provides information for scientists to choose the appropriate artery stenosis model in accordance to the scientific question asked.
    Journal of Visualized Experiments 01/2014; DOI:10.3791/51459
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    ABSTRACT: Rationale: Human embryonic stem cell (hESC) derivatives are attractive candidates for therapeutic use. The engraftment and survival of hESC derivatives as xenografts or allografts require effective immunosuppression to prevent immune cell infiltration and graft destruction. Objective: To test the hypothesis that a short-course, dual-agent regimen of two costimulation-adhesion blockade agents can induce better engraftment of hESC derivatives compared to current immunosuppressive agents. Methods and Results: We transduced hESCs with a double fusion reporter gene construct expressing firefly luciferase (Fluc) and enhanced green fluorescent protein (eGFP), and differentiated these cells to endothelial cells (hESC-ECs). Reporter gene expression enabled longitudinal assessment of cell engraftment by bioluminescence imaging (BLI). Costimulation-adhesion therapy resulted in superior hESC-EC and mouse EC engraftment compared to cyclosporine therapy in a hindlimb model. Costimulation-adhesion therapy also promoted robust hESC-EC and hESC-derived cardiomyocyte (hESC-CM) survival in an ischemic myocardial injury model. Improved hESC-EC engraftment had a cardioprotective effect after myocardial injury, as assessed by magnetic resonance imaging (MRI). Mechanistically, costimulation-adhesion therapy is associated with systemic and intra-graft upregulation of T cell immunoglobulin and mucin domain 3 (TIM3) and a reduced pro-inflammatory cytokine profile. Conclusions: Costimulation-adhesion therapy is a superior alternative to current clinical immunosuppressive strategies for preventing the post-transplant rejection of hESC derivatives. By extending the window for cellular engraftment, costimulation-adhesion therapy enhances functional preservation following ischemic injury. This regimen may function through a TIM3-dependent mechanism. Stem Cells 2013.
    Stem Cells 11/2013; DOI:10.1002/stem.1501 · 7.70 Impact Factor
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    ABSTRACT: Using meta-analysis of eight independent transplant datasets (236 graft biopsy samples) from four organs, we identified a common rejection module (CRM) consisting of 11 genes that were significantly overexpressed in acute rejection (AR) across all transplanted organs. The CRM genes could diagnose AR with high specificity and sensitivity in three additional independent cohorts (794 samples). In another two independent cohorts (151 renal transplant biopsies), the CRM genes correlated with the extent of graft injury and predicted future injury to a graft using protocol biopsies. Inferred drug mechanisms from the literature suggested that two FDA-approved drugs (atorvastatin and dasatinib), approved for nontransplant indications, could regulate specific CRM genes and reduce the number of graft-infiltrating cells during AR. We treated mice with HLA-mismatched mouse cardiac transplant with atorvastatin and dasatinib and showed reduction of the CRM genes, significant reduction of graft-infiltrating cells, and extended graft survival. We further validated the beneficial effect of atorvastatin on graft survival by retrospective analysis of electronic medical records of a single-center cohort of 2,515 renal transplant patients followed for up to 22 yr. In conclusion, we identified a CRM in transplantation that provides new opportunities for diagnosis, drug repositioning, and rational drug design.
    Journal of Experimental Medicine 10/2013; DOI:10.1084/jem.20122709 · 13.91 Impact Factor
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    ABSTRACT: ABSTRACT Aim: In this study, we target the hypoxia inducible factor-1 alpha (HIF-1-alpha) pathway by short hairpin RNA (shRNA) interference therapy targeting prolyl hydroxylase-2 (shPHD2). We use the minicircle (MC) vector technology as an alternative for conventional nonviral plasmid (PL) vectors in order to improve neovascularization after unilateral hindlimb ischemia in a murine model. Methods and Results: Gene expression and transfection efficiency of MC and PL, both in vitro and in vivo, were assessed using bioluminescence imaging (BLI) and firefly Luciferase (Luc) reporter gene. C57Bl6 mice underwent unilateral electro-coagulation of the femoral artery and gastrocnemic muscle injection with MC-shPHD2, PL-shPHD2, or PBS as control. Blood flow recovery (BFR) was monitored using Laser Doppler Perfusion Imaging (LDPI), and collaterals were visualized by immunohistochemistry and angiography. MC-Luc showed a 4.6-fold higher in vitro BLI signal compared to PL-Luc. BLI signals in vivo were 4.3x105±3.3x105 (MC-Luc) versus 0.4x105±0.3x105 (PL-Luc) at day 28 (p=0.016). Compared to PL-shPHD2 or PBS, MC-shPHD2 significantly improved BFR, up to 50% from day 3 until day 14 after ischemia-induction. MC-shPHD2 significantly increased collateral density and capillary density, as monitored by alpha-smooth muscle actin (α-SMA) expression and CD31+ expression, respectively (CD31+: 40.3 MC-shPHD2 versus 18.1 PL-shPHD2 and 11.8 PBS). Angiography data confirmed the histological findings. Significant downregulation of PHD2 mRNA levels by MC-shPHD2 was confirmed by quantitative PCR (qPCR). Finally, Western blot analysis confirmed significant higher levels of HIF-1-alpha protein by MC-shPHD2, compared to PL-shPHD2 and PBS. Conclusions: This study provides initial evidence of a new potential therapeutic approach for peripheral artery disease (PAD). The combination of HIF-1-alpha pathway targeting by shPHD2 with the robust nonviral MC plasmid improved post-ischemic neovascularization, making this approach a promising potential treatment option for critical limb ischemia.
    Human gene therapy 10/2013; DOI:10.1089/hum.2013.110 · 3.62 Impact Factor
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    ABSTRACT: Background—Drug-induced arrhythmia is one of the most common causes of drug development failure and withdrawal from market. This study tested whether human induced pluripotent stem cell–derived cardiomyocytes (hiPSC-CMs) combined with a low-impedance microelectrode array (MEA) system could improve on industry-standard preclinical cardiotoxicity screening methods, identify the effects of well-characterized drugs, and elucidate underlying risk factors for drug-induced arrhythmia. hiPSC-CMs may be advantageous over immortalized cell lines because they possess similar functional characteristics as primary human cardiomyocytes and can be generated in unlimited quantities. Methods and Results—Pharmacological responses of beating embryoid bodies exposed to a comprehensive panel of drugs at 65 to 95 days postinduction were determined. Responses of hiPSC-CMs to drugs were qualitatively and quantitatively consistent with the reported drug effects in literature. Torsadogenic hERG blockers, such as sotalol and quinidine, produced statistically and physiologically significant effects, consistent with patch-clamp studies, on human embryonic stem cell–derived cardiomyocytes hESC-CMs. False-negative and false-positive hERG blockers were identified accurately. Consistent with published studies using animal models, early afterdepolarizations and ectopic beats were observed in 33% and 40% of embryoid bodies treated with sotalol and quinidine, respectively, compared with negligible early afterdepolarizations and ectopic beats in untreated controls. Conclusions—We found that drug-induced arrhythmias can be recapitulated in hiPSC-CMs and documented with low impedance MEA. Our data indicate that the MEA/hiPSC-CM assay is a sensitive, robust, and efficient platform for testing drug effectiveness and for arrhythmia screening. This system may hold great potential for reducing drug development costs and may provide significant advantages over current industry standard assays that use immortalized cell lines or animal models.
    Circulation 09/2013; DOI:10.1161/CIRCULATIONAHA.112.000570 · 14.95 Impact Factor
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    ABSTRACT: The efficacy and safety of cardiac gene therapy depend critically on the level and the distribution of therapeutic gene expression following vector administration. We aimed to develop a titratable two-step transcriptional amplification (tTSTA) vector strategy, which allows modulation of transcriptionally targeted gene expression in the myocardium. We constructed a tTSTA plasmid vector (pcTnT-tTSTA-fluc), which uses the cardiac troponin T (cTnT) promoter to drive the expression of the recombinant transcriptional activator GAL4-mER(LBD)-VP2, whose ability to transactivate the downstream firefly luciferase reporter gene (fluc) depends on the binding of its mutant estrogen receptor (ERG521T) ligand binding domain (LBD) to an ER ligand such as raloxifene. Mice underwent either intramyocardial or hydrodynamic tail vein (HTV) injection of pcTnT-tTSTA-fluc, followed by differential modulation of fluc expression with varying doses of intraperitoneal raloxifene prior to bioluminescence imaging to assess the kinetics of myocardial or hepatic fluc expression. Intramyocardial injection of pcTnT-tTSTA-fluc followed by titration with intraperitoneal raloxifene led to up to tenfold induction of myocardial fluc expression. HTV injection of pcTnT-tTSTA-fluc led to negligible long-term hepatic fluc expression, regardless of the raloxifene dose given. The tTSTA vector strategy can effectively modulate transgene expression in a tissue-specific manner. Further refinement of this strategy should help maximize the benefit-to-risk ratio of cardiac gene therapy.
    Molecular imaging and biology: MIB: the official publication of the Academy of Molecular Imaging 08/2013; DOI:10.1007/s11307-013-0673-4 · 2.87 Impact Factor
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    ABSTRACT: Hypoxia-inducible factor-1 alpha (HIF-1α) gene therapy holds great promise for the treatment of myocardial ischemia. Both pre-clinical and clinical evaluations of this therapy are underway, and can benefit from a vector strategy that allows noninvasive assessment of HIF-1α expression as an objective measure of gene delivery. We have developed a novel bi-directional plasmid vector (pcTnT-HIF-1α-VP2-TSTA-fluc), which employs the cardiac troponin T (cTnT) promoter in conjunction with a two-step transcriptional amplification (TSTA) system to drive the linked expression of a recombinant HIF-1α gene (HIF-1α-VP2) and the firefly luciferase gene (fluc). The firefly luciferase (FLuc) activity serves as a surrogate for HIF-1α-VP2 expression, and can be noninvasively assessed in mice using bioluminescence imaging following vector delivery. Transfection of cultured HL-1 cardiomyocytes with pcTnT-HIF-1α-VP2-TSTA-fluc led to a strong correlation between FLuc and HIF-1α-dependent vascular endothelial growth factor expression ( r <sup>2</sup>=0.88). Intramyocardial delivery of pcTnT-HIF-1α-VP2-TSTA-fluc into infarcted mouse myocardium led to persistent HIF-1α-VP2 expression for 4 weeks, even though it improved neither CD31+ microvessel density nor echocardiographically determined left ventricular systolic function. These results lend support to recent findings of suboptimal efficacy associated with plasmid-mediated HIF-1α therapy. The imaging techniques developed herein should be useful for further optimizing HIF-1α-VP2 therapy in pre-clinical models of myocardial ischemia.
    Human Gene Therapy Methods 08/2013; DOI:10.1089/hgtb.2013.028 · 1.64 Impact Factor
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    ABSTRACT: Mesenchymal stromal cells (MSCs) have been isolated from many tissues including gestational tissue. To date a study comparing the properties and suitability of these cells in cell-based therapies is lacking. In this study we compared the phenotype, proliferation rate, migration, immunogenicity, and immunomodulatory capabilities of human MSCs derived from umbilical cord lining (CL-MSC), umbilical cord blood (CB-MSC), placenta (P-MSC), and Wharton´s jelly (WJ-MSC). Differences were noted in differentiation, proliferation, and migration, with CL-MSCs showing the highest proliferation and migration rates resulting in prolonged survival in immunodeficient mice. Moreover, CL-MSCs showed a prolongation in survival in xenogeneic BALB/c mice which was attributed to their ability to dampen TH1 and TH2 responses. Weaker human cellular immune responses were detected against CL-MSCs and P-MSCs, which were correlated with their lower HLA I expression. Furthermore HLA II was up-regulated less substantially by CL-MSCs and CB-MSCs after IFN-γ stimulation. MSC types did not differ in indolamine 2,3-dioxygenase (IDO) expression after IFN-γ stimulation. Despite their lower IDO, HLA-G, and TGF-β1 expression, only CL-MSCs were able to reduce the release of IFN-γ by lymphocytes in a mixed lymphocyte reaction. In summary, CL-MSCs showed the best characteristics for cell-based strategies, as they are hypo-immunogenic and show high proliferation and migration rates. In addition, these studies show for the first time that although immunomodulatory molecules HLA-G, HLA-E, and TGF-β play an important role in MSC immune evasion, basal and induced HLA expression seems to be decisive in determining the immunogenicity of MSCs.
    Stem cells and development 05/2013; DOI:10.1089/scd.2013.0043 · 4.20 Impact Factor
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    ABSTRACT: BACKGROUND: Lung transplant (LUT) and heart-lung transplant (HLT) represent surgical options for treating medically refractory idiopathic pulmonary arterial hypertension (IPAH). The effect of the lung allocation score (LAS) on waitlist and transplant outcomes in IPAH patients is poorly described. METHODS AND RESULTS: Adults diagnosed with IPAH and listed for transplant in the 80 months before and after the LAS algorithm was implemented (N=1430) were identified in the United Network for Organ Sharing thoracic registry. Patients were stratified by organ listed and pre- and post-LAS era. The cumulative incidences of transplant and mortality for waitlisted patients in both eras were appraised with competing outcomes analysis. Post-transplant survival was assessed with the Kaplan-Meier method. These analyses were repeated in propensity-matched subgroups. Cox proportional hazards analysis evaluated the effect of pre-listing and pre-transplant characteristics on mortality. We found that post-LAS-era patients had significantly worse comorbidities; nevertheless, both LUT and HLT candidates in this era enjoyed lower waitlist mortality and a higher incidence of transplant in our unmatched and propensity-matched analyses. On multivariable analysis, HLT and double-lung transplant (DLT) were associated with improved survival from the time of waitlisting, as was being listed at a medium-to-high-volume institution. Donor/recipient gender matching predicted post-transplant survival. CONCLUSIONS: The incidence of transplant has increased while waitlist mortality has decreased in IPAH patients waitlisted for transplant in the post-LAS era. Both HLT and DLT are predictive of survival in transplant candidates with IPAH, as is being listed at a medium-to-high-volume institution. Donor/recipient gender-matching is associated with better post-transplant survival.
    Circulation 05/2013; 129(16). DOI:10.1161/CIRCULATIONAHA.112.001080 · 14.95 Impact Factor
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  • The Journal of Heart and Lung Transplantation 04/2013; 32(4):S82. DOI:10.1016/j.healun.2013.01.209 · 5.61 Impact Factor
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    ABSTRACT: Mesenchymal stromal cells (MSCs) are utilized in cell-based therapies. In this study we compared bone marrow derived MSCs from a healthy 6 month old infant (iMSC) and multimorbid donors above 70 years (sMSC).Methods and MaterialsCells were characterized by morphology, FACS, and mesenchymal lineage differentiation to confirm their similarity. Their proliferative and migratory potential was compared using the MTT assays and novel living cell imaging. Immunogenicity of MSCs was assessed by flow cytometry for surface molecules, in vivo ELISPOT assays using Balb/C mice, and demonstration of donor specific antibodies.ResultsBoth groups of MSCs showed typical spindle shaped morphology, plastic adherence, and the same potential to differentiate into cells of the mesenchymal lineage. Both iMSC and sMSC expressed cell typical surface markers, such as CD90, CD105, as well as CD44 and were negative for CD45, CD34, CD31 and CD117. Differences were noted in the biology of cells: iMSCs showed higher proliferation (p<0.001) and migration (p<0.001) rates compared to sMSC. No significant differences were observed between iMSCs and sMSCs for HLA class I-, β2 microglobulin-, HLA class II-, and costimulatory molecule expression. Immunological relevant molecules as well as immunomodulatory molecules were increased in the presence of IFNγ. Both iMSCs as well as sMSCs provoked similar low TH1 and TH2 responses in unidirectional ELISPOT assays in vivo (spot frequencies IFNγ:106±49 vs. 80±73 and for IL-4: 108±70 vs. 105±107, respectively). Also no differences between groups were observed for IgM donorspecific antibodies (iMSC: 145.8±31.1 vs sMSC: 113.2±27.6; p= ns).Conclusions Our results suggest that donor age does not seem to influence the immunogenicity and immunomodulatory properties of bone marrow derived MSCs. Their clinical use, however, might be limited by their significant lower proliferation capacity compared to younger cell sources.
    The Journal of Heart and Lung Transplantation 04/2013; 32(4):S299-S300. DOI:10.1016/j.healun.2013.01.854 · 5.61 Impact Factor

Publication Stats

12k Citations
2,637.30 Total Impact Points

Institutions

  • 1995–2015
    • Stanford Medicine
      • • Stanford Cardiovascular Institute
      • • Division of Cardiovascular Medicine
      • • Department of Cardiothoracic Surgery
      • • Division of Vascular and Endovascular Surgery
      • • Division of Interventional Radiology
      Stanford, California, United States
  • 1996–2014
    • Stanford University
      • • Department of Cardiothoracic Surgery
      • • Department of Pediatrics
      • • Division of Cardiovascular Medicine
      • • Division of Pulmonary and Critical Care Medicine
      Palo Alto, California, United States
    • University of Maryland, Baltimore
      Baltimore, Maryland, United States
  • 2012
    • Baylor College of Medicine
      Houston, Texas, United States
  • 2010
    • Universitätsklinikum Münster
      Muenster, North Rhine-Westphalia, Germany
  • 2009
    • University of Mississippi Medical Center
      • Division of Cardiothoracic Surgery
      Jackson, Mississippi, United States
    • University of Hamburg
      Hamburg, Hamburg, Germany
  • 2008
    • National Academies
      Washington, Washington, D.C., United States
  • 2007
    • Westchester Medical Center
      Valhalla, New York, United States
  • 2005
    • Beth Israel Deaconess Medical Center
      Boston, Massachusetts, United States
  • 2000–2005
    • Leiden University
      Leyden, South Holland, Netherlands
    • The Children's Hospital of Philadelphia
      Philadelphia, Pennsylvania, United States
  • 1998
    • Nagoya University
      • Division of Thoracic Surgery
      Nagoya-shi, Aichi-ken, Japan
  • 1997
    • Columbia University
      • Department of Medicine
      New York City, NY, United States