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Wintruba KL, Hill JC, Richards TD, Lee YC, Kaczorowski DJ, Sultan I, Badylak SF, Billaud M, Gleason TG, Phillippi JA. Adventitia-derived extracellular matrix hydrogel enhances contractility of human vasa vasorum-derived pericytes via α 2 β 1 integrin and TGFβ receptor. J Biomed Mater Res A 2022; 110:1912-1920. [PMID: 35770946 DOI: 10.1002/jbm.a.37422] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2022] [Revised: 06/07/2022] [Accepted: 06/15/2022] [Indexed: 11/11/2022]
Abstract
Pericytes are essential components of small blood vessels and are found in human aortic vasa vasorum. Prior work uncovered lower vasa vasorum density and decreased levels of pro-angiogenic growth factors in adventitial specimens of human ascending thoracic aortic aneurysm. We hypothesized that adventitial extracellular matrix (ECM) from normal aorta promotes pericyte function by increasing pericyte contractile function through mechanisms deficient in ECM derived from aneurysmal aortic adventitia. ECM biomaterials were prepared as lyophilized particulates from decellularized adventitial specimens of human and porcine aorta. Immortalized human aortic adventitia-derived pericytes were cultured within Type I collagen gels in the presence or absence of human or porcine adventitial ECMs. Cell contractility index was quantified by measuring the gel area immediately following gelation and after 48 h of culture. Normal human and porcine adventitial ECM increased contractility of pericytes when compared with pericytes cultured in absence of adventitial ECM. In contrast, aneurysm-derived human adventitial ECM failed to promote pericyte contractility. Pharmacological inhibition of TGFβR1 and antibody blockade of α2 β1 integrin independently decreased porcine adventitial ECM-induced pericyte contractility. By increasing pericyte contractility, adventitial ECM may improve microvascular function and thus represents a candidate biomaterial for less invasive and preventative treatment of human ascending aortic disease.
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Affiliation(s)
- Kaitlyn L Wintruba
- Department of Cardiothoracic Surgery, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
| | - Jennifer C Hill
- Department of Cardiothoracic Surgery, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
| | - Tara D Richards
- Department of Cardiothoracic Surgery, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
| | - Yoojin C Lee
- Department of Cardiothoracic Surgery, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
| | - David J Kaczorowski
- Department of Cardiothoracic Surgery, University of Pittsburgh, Pittsburgh, Pennsylvania, USA.,Heart and Vascular Institute, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania, USA.,McGowan Institute for Regenerative Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
| | - Ibrahim Sultan
- Department of Cardiothoracic Surgery, University of Pittsburgh, Pittsburgh, Pennsylvania, USA.,Heart and Vascular Institute, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania, USA
| | - Stephen F Badylak
- McGowan Institute for Regenerative Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, USA.,Bioengineering, University of Pittsburgh, Pittsburgh, Pennsylvania, USA.,Department of Surgery, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
| | - Marie Billaud
- Department of Surgery, Division of Thoracic and Cardiac Surgery, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - Thomas G Gleason
- Department of Cardiothoracic Surgery, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
| | - Julie A Phillippi
- Department of Cardiothoracic Surgery, University of Pittsburgh, Pittsburgh, Pennsylvania, USA.,Heart and Vascular Institute, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania, USA.,Bioengineering, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
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Hill JC, Billaud M, Richards TD, Kotlarczyk MP, Shiva S, Phillippi JA, Gleason TG. OUP accepted manuscript. Eur J Cardiothorac Surg 2022; 62:6573262. [PMID: 35460403 PMCID: PMC9615433 DOI: 10.1093/ejcts/ezac237] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/14/2021] [Revised: 03/08/2022] [Accepted: 03/29/2022] [Indexed: 11/14/2022] Open
Abstract
OBJECTIVES We hypothesized that expression and activity of nitric oxide synthase-3 enzyme (Nos3) in bicuspid aortic valve (BAV) aortopathy are related to tissue layer and Nos3 genotype. METHODS Gene expression of Nos3 and platelet and endothelial cell adhesion molecule-1 (Pecam1) and NOS activity were measured in intima-containing media and adventitial specimens of ascending aortic tissue. The presence of 2 Nos3 single-nucleotide polymorphisms (SNPs; -786T/C and 894G/T) was determined for non-aneurysmal (NA) and aneurysmal patients with BAV (n = 40, 89, respectively); patients with tricuspid aortic valve (TAV) and aneurysm (n = 151); and NA patients with TAV (n = 100). RESULTS Elevated Nos3 relative to Pecam1 and reduced Pecam1 relative to a housekeeping gene were observed within intima-containing aortic specimens from BAV patients when compared with TAV patients. Lower Nos3 in the adventitia of aneurysmal specimens was noted when compared with specimens of NA aorta, independent of valve morphology. NOS activity was similar among cohorts in media/intima and decreased in the diseased adventitia, relative to control patients. Aneurysmal BAV patients exhibited an under-representation of the wild-type genotype for -786 SNP. No differences in genotype distribution were noted for 894 SNP. Primary intimal endothelial cells from patients with at least 1 C allele at -786 SNP exhibited lower Nos3 when compared with wild-type cells. CONCLUSIONS These findings of differential Nos3 in media/intima versus adventitia depending on valve morphology or aneurysm reveal new information regarding aneurysmal pathophysiology and support our ongoing assertion that there are distinct mechanisms giving rise to ascending aortopathy in BAV and TAV patients.
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Affiliation(s)
- Jennifer C Hill
- Department of Cardiothoracic Surgery, University of Pittsburgh, Pittsburgh, PA, USA
| | - Marie Billaud
- Department of Surgery, Division of Thoracic and Cardiac Surgery, Brigham and Women’s Hospital, Boston, MA, USA
| | - Tara D Richards
- Department of Cardiothoracic Surgery, University of Pittsburgh, Pittsburgh, PA, USA
| | - Mary P Kotlarczyk
- Department of Medicine, Division of Geriatric Medicine, University of Pittsburgh, Pittsburgh, PA, USA
| | - Sruti Shiva
- Department of Pharmacology and Chemical Biology, University of Pittsburgh, Pittsburgh, PA, USA
- Vascular Medicine Institute, University of Pittsburgh, Pittsburgh, PA, USA
- Department of Bioengineering, University of Pittsburgh, Pittsburgh, PA, USA
| | - Julie A Phillippi
- Department of Cardiothoracic Surgery, University of Pittsburgh, Pittsburgh, PA, USA
- Department of Bioengineering, University of Pittsburgh, Pittsburgh, PA, USA
- McGowan Institute for Regenerative Medicine, University of Pittsburgh, Pittsburgh, PA, USA
- Corresponding authors. University of Pittsburgh 450 Technology Drive, Suite 300, Pittsburgh, PA 15219, USA. Tel: +1-412-624-6704; e-mail: (J.A. Phillippi) and (T.G. Gleason)
| | - Thomas G Gleason
- Department of Cardiothoracic Surgery, University of Pittsburgh, Pittsburgh, PA, USA
- McGowan Institute for Regenerative Medicine, University of Pittsburgh, Pittsburgh, PA, USA
- Corresponding authors. University of Pittsburgh 450 Technology Drive, Suite 300, Pittsburgh, PA 15219, USA. Tel: +1-412-624-6704; e-mail: (J.A. Phillippi) and (T.G. Gleason)
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Billaud M, Hill JC, Richards TD, Gleason TG, Phillippi JA. Medial Hypoxia and Adventitial Vasa Vasorum Remodeling in Human Ascending Aortic Aneurysm. Front Cardiovasc Med 2018; 5:124. [PMID: 30276199 PMCID: PMC6151311 DOI: 10.3389/fcvm.2018.00124] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2018] [Accepted: 08/20/2018] [Indexed: 11/29/2022] Open
Abstract
Human ascending aortic aneurysms characteristically exhibit cystic medial degeneration of the aortic wall encompassing elastin degeneration, proteoglycan accumulation and smooth muscle cell loss. Most studies have focused on the aortic media and there is a limited understanding of the importance of the adventitial layer in the setting of human aneurysmal disease. We recently demonstrated that the adventitial ECM contains key angiogenic factors that are downregulated in aneurysmal aortic specimens. In this study, we investigated the adventitial microvascular network (vasa vasorum) of aneurysmal aortic specimens of different etiology and hypothesized that the vasa vasorum is disrupted in patients with ascending aortic aneurysm. Morphometric analyses of hematoxylin and eosin-stained human aortic cross-sections revealed evidence of vasa vasorum remodeling in aneurysmal specimens, including reduced density of vessels, increased lumen area and thickening of smooth muscle actin-positive layers. These alterations were inconsistently observed in specimens of bicuspid aortic valve (BAV)-associated aortopathy, while vasa vasorum remodeling was typically observed in aneurysms arising in patients with the morphologically normal tricuspid aortic valve (TAV). Gene expression of hypoxia-inducible factor 1α and its downstream targets, metallothionein 1A and the pro-angiogenic factor vascular endothelial growth factor, were down-regulated in the adventitia of aneurysmal specimens when compared with non-aneurysmal specimens, while the level of the anti-angiogenic factor thrombospondin-1 was elevated. Immunodetection of glucose transporter 1 (GLUT1), a marker of chronic tissue hypoxia, was minimal in non-aneurysmal medial specimens, and locally accumulated within regions of elastin degeneration, particularly in TAV-associated aneurysms. Quantification of GLUT1 revealed elevated levels in the aortic media of TAV-associated aneurysms when compared to non-aneurysmal counterparts. We detected evidence of chronic inflammation as infiltration of lymphoplasmacytic cells in aneurysmal specimens, with a higher prevalence of lymphoplasmacytic infiltrates in aneurysmal specimens from patients with TAV compared to that of patients with BAV. These data highlight differences in vasa vasorum remodeling and associated medial chronic hypoxia markers between aneurysms of different etiology. These aberrations could contribute to malnourishment of the aortic media and could conceivably participate in the pathogenesis of thoracic aortic aneurysm.
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Affiliation(s)
- Marie Billaud
- Department of Cardiothoracic Surgery, University of Pittsburgh, Pittsburgh, PA, United States.,McGowan Institute for Regenerative Medicine, University of Pittsburgh, Pittsburgh, PA, United States.,Department of Bioengineering, University of Pittsburgh, Pittsburgh, PA, United States
| | - Jennifer C Hill
- Department of Cardiothoracic Surgery, University of Pittsburgh, Pittsburgh, PA, United States
| | - Tara D Richards
- Department of Cardiothoracic Surgery, University of Pittsburgh, Pittsburgh, PA, United States
| | - Thomas G Gleason
- Department of Cardiothoracic Surgery, University of Pittsburgh, Pittsburgh, PA, United States.,McGowan Institute for Regenerative Medicine, University of Pittsburgh, Pittsburgh, PA, United States.,Department of Bioengineering, University of Pittsburgh, Pittsburgh, PA, United States.,Center for Vascular Remodeling and Regeneration, University of Pittsburgh, Pittsburgh, PA, United States
| | - Julie A Phillippi
- Department of Cardiothoracic Surgery, University of Pittsburgh, Pittsburgh, PA, United States.,McGowan Institute for Regenerative Medicine, University of Pittsburgh, Pittsburgh, PA, United States.,Department of Bioengineering, University of Pittsburgh, Pittsburgh, PA, United States.,Center for Vascular Remodeling and Regeneration, University of Pittsburgh, Pittsburgh, PA, United States
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Billaud M, Donnenberg VS, Ellis BW, Meyer EM, Donnenberg AD, Hill JC, Richards TD, Gleason TG, Phillippi JA. Classification and Functional Characterization of Vasa Vasorum-Associated Perivascular Progenitor Cells in Human Aorta. Stem Cell Reports 2017; 9:292-303. [PMID: 28552602 PMCID: PMC5511043 DOI: 10.1016/j.stemcr.2017.04.028] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2016] [Revised: 04/25/2017] [Accepted: 04/26/2017] [Indexed: 01/27/2023] Open
Abstract
In the microcirculation, pericytes are believed to function as mesenchymal stromal cells (MSCs). We hypothesized that the vasa vasorum harbor progenitor cells within the adventitia of human aorta. Pericytes, endothelial progenitor cells, and other cell subpopulations were detected among freshly isolated adventitial cells using flow cytometry. Purified cultured pericytes were enriched for the MSC markers CD105 and CD73 and depleted of the endothelial markers von Willebrand factor and CD31. Cultured pericytes were capable of smooth muscle lineage progression including inducible expression of smooth muscle myosin heavy chain, calponin, and α-smooth muscle actin, and adopted a spindle shape. Pericytes formed spheroids when cultured on Matrigel substrates and peripherally localized with branching endothelial cells in vitro. Our results indicate that the vasa vasorum form a progenitor cell niche distinct from other previously described progenitor populations in human adventitia. These findings could have important implications for understanding the complex pathophysiology of human aortic disease. Perivascular progenitor cells were classified in human ascending aorta Adventitial vasa vasorum were identified as a progenitor cell niche Purified pericytes were functional in vitro as smooth muscle cell progenitors Branching endothelial cell networks were associated with pericytes in vitro
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Affiliation(s)
- Marie Billaud
- Department of Cardiothoracic Surgery, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213, USA; McGowan Institute for Regenerative Medicine, University of Pittsburgh, Pittsburgh, PA 15213, USA; Department of Bioengineering, Swanson School of Engineering, University of Pittsburgh, Pittsburgh, PA 15213, USA
| | - Vera S Donnenberg
- Department of Cardiothoracic Surgery, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213, USA; McGowan Institute for Regenerative Medicine, University of Pittsburgh, Pittsburgh, PA 15213, USA; University of Pittsburgh Cancer Institute, University of Pittsburgh, Pittsburgh, PA 15213, USA
| | - Bradley W Ellis
- Department of Cardiothoracic Surgery, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213, USA
| | - E Michael Meyer
- University of Pittsburgh Cancer Institute, University of Pittsburgh, Pittsburgh, PA 15213, USA
| | - Albert D Donnenberg
- McGowan Institute for Regenerative Medicine, University of Pittsburgh, Pittsburgh, PA 15213, USA; University of Pittsburgh Cancer Institute, University of Pittsburgh, Pittsburgh, PA 15213, USA; Department of Medicine, University of Pittsburgh School of Medicine, University of Pittsburgh, Pittsburgh, PA 15232, USA
| | - Jennifer C Hill
- Department of Cardiothoracic Surgery, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213, USA
| | - Tara D Richards
- Department of Cardiothoracic Surgery, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213, USA
| | - Thomas G Gleason
- Department of Cardiothoracic Surgery, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213, USA; McGowan Institute for Regenerative Medicine, University of Pittsburgh, Pittsburgh, PA 15213, USA; Department of Bioengineering, Swanson School of Engineering, University of Pittsburgh, Pittsburgh, PA 15213, USA
| | - Julie A Phillippi
- Department of Cardiothoracic Surgery, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213, USA; McGowan Institute for Regenerative Medicine, University of Pittsburgh, Pittsburgh, PA 15213, USA; Department of Bioengineering, Swanson School of Engineering, University of Pittsburgh, Pittsburgh, PA 15213, USA.
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5
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Fercana GR, Yerneni S, Billaud M, Hill JC, VanRyzin P, Richards TD, Sicari BM, Johnson SA, Badylak SF, Campbell PG, Gleason TG, Phillippi JA. Perivascular extracellular matrix hydrogels mimic native matrix microarchitecture and promote angiogenesis via basic fibroblast growth factor. Biomaterials 2017; 123:142-154. [PMID: 28167392 DOI: 10.1016/j.biomaterials.2017.01.037] [Citation(s) in RCA: 47] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2016] [Accepted: 01/27/2017] [Indexed: 01/12/2023]
Abstract
Extracellular matrix (ECM)-derived bioscaffolds have been shown to elicit tissue repair through retention of bioactive signals. Given that the adventitia of large blood vessels is a richly vascularized microenvironment, we hypothesized that perivascular ECM contains bioactive signals that influence cells of blood vessel lineages. ECM bioscaffolds were derived from decellularized human and porcine aortic adventitia (hAdv and pAdv, respectively) and then shown have minimal DNA content and retain elastin and collagen proteins. Hydrogel formulations of hAdv and pAdv ECM bioscaffolds exhibited gelation kinetics similar to ECM hydrogels derived from porcine small intestinal submucosa (pSIS). hAdv and pAdv ECM hydrogels displayed thinner, less undulated, and fibrous microarchitecture reminiscent of native adventitia, with slight differences in ultrastructure visible in comparison to pSIS ECM hydrogels. Pepsin-digested pAdv and pSIS ECM bioscaffolds increased proliferation of human adventitia-derived endothelial cells and this effect was mediated in part by basic fibroblast growth factor (FGF2). Human endothelial cells cultured on Matrigel substrates formed more numerous and longer tube-like structures when supplemented with pAdv ECM bioscaffolds, and FGF2 mediated this matrix signaling. ECM bioscaffolds derived from pAdv promoted FGF2-dependent in vivo angiogenesis in the chick chorioallantoic membrane model. Using an angiogenesis-focused protein array, we detected 55 angiogenesis-related proteins, including FGF2 in hAdv, pAdv and pSIS ECMs. Interestingly, 19 of these factors were less abundant in ECMs bioscaffolds derived from aneurysmal specimens of human aorta when compared with non-aneurysmal (normal) specimens. This study reveals that Adv ECM hydrogels recapitulate matrix fiber microarchitecture of native adventitia, and retain angiogenesis-related actors and bioactive properties such as FGF2 signaling capable of influencing processes important for angiogenesis. This work supports the use of Adv ECM bioscaffolds for both discovery biology and potential translation towards microvascular regeneration in clinical applications.
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Affiliation(s)
- George R Fercana
- Department of Cardiothoracic Surgery, McGowan Institute for Regenerative Medicine, University of Pittsburgh School of Medicine, Pittsburgh, PA
| | - Saigopalakrishna Yerneni
- Department of Cardiothoracic Surgery, McGowan Institute for Regenerative Medicine, University of Pittsburgh School of Medicine, Pittsburgh, PA
| | - Marie Billaud
- Department of Cardiothoracic Surgery, McGowan Institute for Regenerative Medicine, University of Pittsburgh School of Medicine, Pittsburgh, PA
| | - Jennifer C Hill
- Department of Cardiothoracic Surgery, McGowan Institute for Regenerative Medicine, University of Pittsburgh School of Medicine, Pittsburgh, PA
| | - Paul VanRyzin
- Department of Cardiothoracic Surgery, McGowan Institute for Regenerative Medicine, University of Pittsburgh School of Medicine, Pittsburgh, PA
| | - Tara D Richards
- Department of Cardiothoracic Surgery, McGowan Institute for Regenerative Medicine, University of Pittsburgh School of Medicine, Pittsburgh, PA
| | - Brian M Sicari
- Department of Cardiothoracic Surgery, McGowan Institute for Regenerative Medicine, University of Pittsburgh School of Medicine, Pittsburgh, PA
| | - Scott A Johnson
- Department of Cardiothoracic Surgery, McGowan Institute for Regenerative Medicine, University of Pittsburgh School of Medicine, Pittsburgh, PA
| | - Stephen F Badylak
- Department of Cardiothoracic Surgery, McGowan Institute for Regenerative Medicine, University of Pittsburgh School of Medicine, Pittsburgh, PA
| | - Phil G Campbell
- Department of Cardiothoracic Surgery, McGowan Institute for Regenerative Medicine, University of Pittsburgh School of Medicine, Pittsburgh, PA
| | - Thomas G Gleason
- Department of Cardiothoracic Surgery, McGowan Institute for Regenerative Medicine, University of Pittsburgh School of Medicine, Pittsburgh, PA
| | - Julie A Phillippi
- Department of Cardiothoracic Surgery, McGowan Institute for Regenerative Medicine, University of Pittsburgh School of Medicine, Pittsburgh, PA
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Chen Y, Tillman BW, Cho SK, Richards TD, Tevar AD, Gu X, Wagner WR, Chun Y. A novel compartmentalised stent graft to isolate the perfusion of the abdominal organs. J Med Eng Technol 2016; 41:141-150. [PMID: 27715350 DOI: 10.1080/03091902.2016.1239279] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
Donation after cardiac death has been adopted to address the critical shortage of donor organs for transplant. Recovery of these organs is hindered by low blood flow that leads to permanent organ injury. We propose a novel approach to isolate the perfusion of the abdominal organs from the systemic malperfusion of the dying donor. We reasoned that this design could improve blood flow to organs without open surgery, while respecting the ethical principle that cardiac stress not be increased during organ recovery. Conditions within the stent were analysed using a computational fluid dynamics (CFD) method and validated on two prototypes in vitro. The hydrodynamic pressure drop across the stent was measured as 0.14-0.22 mmHg, which is a negligible influence. Device placement studies were also conducted on swine model fluoroscopically. All these results demonstrated the feasibility of rapidly isolating the perfusion to abdominal organs using a compartmentalised stent graft design.
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Affiliation(s)
- Yanfei Chen
- a Department of Industrial Engineering , University of Pittsburgh , Pittsburgh , PA , USA
| | - Bryan W Tillman
- b Division of Vascular Surgery , University of Pittsburgh Medical Centre , Pittsburgh , PA , USA.,c Department of Surgery , University of Pittsburgh , Pittsburgh , PA , USA.,d McGowan Institute for Regenerative Medicine, University of Pittsburgh , Pittsburgh , PA , USA
| | - Sung Kwon Cho
- e Department of Mechanical Engineering and Materials Science , University of Pittsburgh , Pittsburgh, Pittsburgh , PA , USA
| | - Tara D Richards
- c Department of Surgery , University of Pittsburgh , Pittsburgh , PA , USA
| | - Amit D Tevar
- c Department of Surgery , University of Pittsburgh , Pittsburgh , PA , USA.,f Thomas E. Starzl Transplantation Institute, University of Pittsburgh Medical Centre , Pittsburgh , PA , USA
| | - Xinzhu Gu
- d McGowan Institute for Regenerative Medicine, University of Pittsburgh , Pittsburgh , PA , USA
| | - William R Wagner
- c Department of Surgery , University of Pittsburgh , Pittsburgh , PA , USA.,d McGowan Institute for Regenerative Medicine, University of Pittsburgh , Pittsburgh , PA , USA.,g Department of Bioengineering , University of Pittsburgh , Pittsburgh , PA , USA.,h Department of Chemical and Petroleum Engineering , University of Pittsburgh , Pittsburgh , PA , USA
| | - Youngjae Chun
- a Department of Industrial Engineering , University of Pittsburgh , Pittsburgh , PA , USA.,d McGowan Institute for Regenerative Medicine, University of Pittsburgh , Pittsburgh , PA , USA.,g Department of Bioengineering , University of Pittsburgh , Pittsburgh , PA , USA
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Tillman BW, Kelly J, Richards TD, Chen AF, Donnenberg AD, Donnenberg VS, Tzeng E. A depleting antibody toward sca-1 mitigates a surge of CD34+/c-kit+ progenitors and reduces vascular restenosis in a murine vascular injury model. J Vasc Surg 2016; 64:1084-92. [DOI: 10.1016/j.jvs.2015.05.002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2015] [Accepted: 05/03/2015] [Indexed: 10/21/2022]
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Tillman BW, Richards TD, Chen A, Donnenberg AD, Donnenberg V. Progenitor Mechanisms of Vascular Injury in Restenosis. J Am Coll Surg 2014. [DOI: 10.1016/j.jamcollsurg.2014.07.383] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Tillman BW, Kelly J, Richards TD, Chen AF, Donnenberg AD, Donnenberg V. Abstract 187: Prevention of Circulating Progenitor Surge After Vascular Injury Effectively Reduces Restenosis. Arterioscler Thromb Vasc Biol 2014. [DOI: 10.1161/atvb.34.suppl_1.187] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Background:
Restenosis is an aberrant healing response that leads to failure of half of all vascular interventions and circulating progenitor cells have been implicated in restenotic pathology. Based on our previous findings of a surge specific to macrovascular injury, we hypothesized that a surge among progenitors and vascular injury signaling would be evident in the murine model and that an approach to prevent this surge would reduce restenosis.
Methods:
C57BL6 mice underwent injury of the femoral artery following either a depleting antibody to the progenitor marker sca-1 or a control antibody (n=8 per group). A third group had a non-vascular surgery (n=5). Antibody was administered pre-op and then until day 9. Blood and bone marrow were collected on days 1, 3, and 9 and analyzed by flow cytometry for progenitor markers CD34 and c-kit. Plasma was analyzed for the vascular injury signal, stromal cell-derived factor 1/CXCL12 (sdf1alpha). Vessel explants were imaged with lectin microscopy. Finally, animals treated with either sca-1 depleting antibody (n=4) or an isotype control (n=3) underwent vessel explant at 28 days and a lumen ratio was calculated.
Results:
Microscopy confirmed injury of endothelial monolayer and serologically, wire injury increased sdf1alpha by over 3 fold. Injury of the femoral artery resulted in a surge of CD34+/c-kit+ progenitors by over 2.2 fold relative to non-operative controls with a peak on day 1. Furthermore, this surge was prevented by treatment with a sca-1 antibody (P= 0.004). At 28 days, progenitor depletion increased the lumen from 20% among isotype treated controls to 79% among animals treated with direct progenitor depletion (P=0.04).
Conclusions:
It has not been previously demonstrated whether changes among progenitor cells impact restenotic pathology. Our findings suggest that a surge occurs in both a key vascular injury cytokine and among circulating progenitor cells after macrovascular injury. We have further demonstrated the efficacy of a depleting sca-1 antibody to mitigate progenitor surge and most importantly to reduce restenosis in a significant fashion. Future studies of strategies to block circulating progenitor cells may provide new therapies for this prevalent life and limb threatening disease.
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Affiliation(s)
- Bryan W Tillman
- Div of Vascular Surgery, Dept of Surgery, Univ of Pittsburgh Med Cntr, Pittsburgh, PA
| | - Jeremy Kelly
- McGowan Institute for Regenerative Medicine, Univ of Pittsburgh, Pittsburgh, PA
| | - Tara D Richards
- McGowan Institute for Regenerative Medicine, Univ of Pittsburgh, Pittsburgh, PA
| | - Alex F Chen
- Dept of Surgery, Univ of Pittsburgh Sch of Medicine, Pittsburgh, PA
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Richards TD. New GP contract and European definition. Br J Gen Pract 2003; 53:155-6. [PMID: 12817378 PMCID: PMC1314532] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/03/2023] Open
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Abstract
The kinetics of iron release from Azotobacter vinelandii bacterial ferritin (AVBF) was measured by reduction of core iron with S2O4(2-) followed by chelation of Fe2+ with alpha, alpha-bipyridine (bipy). The rate was first order in AVBF and one half order in S2O4(2-), suggesting that SO2- is the active reductant formed by S2O4(2-) = 2SO2-. With zero-order conditions for dithionite and bipy, two consecutive first-order iron release reactions differing by a factor of about 14 were observed with rate constants of 0.0263 and 0.00184 sec-1, respectively, at 25 degrees C and pH 7.0. The faster reaction corresponded to the loss of 1433 iron atoms (91%) and the slower second reaction corresponded to loss of 145 (9%) of the original 1575 iron atoms present. The first reaction increased about twofold with pH variation between 6.5 and 8.0, whereas the second reaction was unchanged in the pH range 5.5-8. Both dramatically increased at pH 5.0. Methyl viologen increased the rate of both reactions about tenfold. The biphasic behavior for iron loss is interpreted as two different populations of iron atoms present in the core of AVBF, the first representing the bulk iron, and the second a group of unique iron atoms released last which may represent iron attached to the interior of the protein shell or iron associated with the heme groups. Kinetic stopped-flow measurements show that the heme is first reduced, followed by reduction of the core iron by reduced heme, suggesting an electron transfer role for heme in AVBF function.
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Affiliation(s)
- T D Richards
- Department of Chemistry and Biochemistry, Brigham Young University, Provo, Utah 84602, USA
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Richards TD. Points: Clawing back income. West J Med 1984. [DOI: 10.1136/bmj.289.6459.1698-b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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Richards TD. External ophthalmomyiasis caused by Oestrus ovis. S Afr Med J 1982; 61:32. [PMID: 7058403] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
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Richards TD. A4 record system and all that. West J Med 1981. [DOI: 10.1136/bmj.282.6275.1552] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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Richards TD. Contraceptives on the N.H.S. Br Med J 1973; 2:244-5. [PMID: 4700023 PMCID: PMC1589406 DOI: 10.1136/bmj.2.5860.244-d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
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