Deliang Shen

Publications (2)21.94 Total impact

• Article: Mechanism of Extravasation of Infused Regenerative Cells From Microvessels into Tissue Parenchyma.

  Ke Cheng, Deliang Shen, Yucai Xie, Eugenio Cingolani, Konstantinos Malliaras, Eduardo Marbán
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  ABSTRACT: In order for bloodborne stem cells to be effective in tissue regeneration, cells must cross vessel walls and enter the parenchyma. Although such transmigration does occur, the mechanism remains elusive. Leukocytes invade tissue by diapedesis; stem cells are commonly assumed to do likewise, but evidence is lacking. Cardiac-derived regenerative cells and multi-cellular cardiospheres were infused into the coronary vessels of rat hearts. Serial histology revealed a novel mechanism of cell transmigration, "active vascular expulsion", which underlies the extravasation of infused cells and cell aggregates. In this mechanism, the vascular barrier undergoes extensive remodeling, while the cells themselves are relatively passive. The mechanism was confirmed in vivo by serial intravital microscopy of cardiosphere extravasation in a dorsal skin flap model. Integrins and matrix metalloproteinases play critical roles in active vascular expulsion. In vitro models reveal that active vascular expulsion is generalizable to other stem cell types and to breast cancer cells. Recognition of active vascular expulsion as a mechanism for transvascular cell migration opens new opportunities to enhance the efficacy of vascularly-delivered cell therapy.
  Stem Cells 11/2012; · 7.78 Impact Factor
• Article: Intramyocardial injection of platelet gel promotes endogenous repair and augments cardiac function in rats with myocardial infarction.

  Ke Cheng, Konstantinos Malliaras, Deliang Shen, Eleni Tseliou, Vittoria Ionta, Jeremy Smith, Giselle Galang, Baiming Sun, Christiane Houde, Eduardo Marbán
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  ABSTRACT: This study sought to explore the therapeutic potential of platelet gel for the treatment of myocardial infarction. Cardiac dysfunction after acute myocardial infarction is a major cause of heart failure. Current therapy relies on prompt reperfusion and blockage of secondary maladaptive pathways by small molecules. Platelet gels are biomaterials rich in cytokines and growth factors, which can be manufactured in an autologous manner and are effective in various models of wound healing. However, the potential utility of platelet gel in cardiac regeneration has yet to be tested. Platelet gel was derived from syngeneic rats and its morphology, biocompatibility, secretion of beneficial factors, and in vivo degradation profile were characterized. After delivery into infarcted rat hearts, the gel was efficiently infiltrated by cardiomyocytes and endothelial cells. Gel-treated hearts exhibited enhanced tissue protection, greater recruitment of endogenous regeneration, higher capillary density, and less compensatory myocyte hypertrophy. The cardiac function of control-injected animals deteriorated over the 6-week time course, while that of platelet gel-injected animals did not. In addition, the gel did not exacerbate inflammation in the heart. Intramyocardial injection of autologous platelet gel ameliorated cardiac dysfunction after myocardial infarction. The striking functional benefits, the simplicity of manufacturing, and the potentially autologous nature of this biomaterial provide impetus for further translation.
  Journal of the American College of Cardiology 01/2012; 59(3):256-64. · 14.16 Impact Factor