Therapeutic Angiogenesis by Implantation of a Capillary Structure Constituted of Human Adipose Tissue Microvascular Endothelial Cells

Abstract

Objective-We previously reported a novel technology for the engineering of a capillary network using an optical lithographic technique. To apply this technology to the therapy of ischemic diseases, we tested human omental microvascular endothelial cells (HOMECs) as an autologous cell source and decellularized human amniotic membranes (DC-AMs) as a pathogen-free and low immunogenic transplantation scaffold. Methods and Results-Human umbilical vein endothelial cells were aligned on a patterned glass substrate and formed a capillary structure when transferred onto an amniotic membrane (AM). In contrast, HOMECs were scattered and did not form a capillary structure on AMs. Treatment of HOMECs with sphingosine 1-phosphate (S1P) inhibited HOMEC migration and enabled HOMEC formation of a capillary structure on AMs. Using quantitative RT-PCR and Western blot analyses, we demonstrated that the main S1P receptor in HOMECs is S1P 2 , which is lacking in human umbilical vein endothelial cells, and that inhibition of cell migration by S1P is mediated through an S1P 2 -Rho-Rho-associated kinase signaling pathway. Implantation of capillaries engineered on DC-AMs into a hindlimb ischemic nude mouse model significantly increased blood perfusion compared with controls. Conclusion-A capillary network consisting of HOMECs on DC-AMs can be engineered ex vivo using printing technology and S1P treatment. This method for regeneration of a capillary network may have therapeutic potential for ischemic diseases. Key Words: angiogenesis Ⅲ angioplasty Ⅲ endothelium Ⅲ ischemia Ⅲ peripheral arterial disease Ⅲ vascular biology I schemic diseases, including peripheral arterial diseases (PADs), myocardial infarction, and cerebral infarction, threaten our health and our lives. When medication becomes ineffective, patients need to undergo percutaneous transluminal angioplasty or artery bypass grafting. Recently, therapeutic angiogenesis has been developed for no-option patients. The target of percutaneous transluminal angioplasty and artery bypass grafting is blood vessels with a diameter larger than 1 mm, whereas that of angiogenic therapy is capillaries and microvessels with a diameter on the micrometer order. See accompanying article on page 1277Therapeutic angiogenesis consists of 2 strategies: (1) growth factor therapy and (2) cell therapy. It has been applied to ischemic diseases, including PADs, such as arteriosclerosis obliterans and Burger's disease, as well as myocardial infarction and cerebral infarction. 1,2 The aim of growth factor therapy is to induce angiogenesis by gene therapy or by protein administration of angiogenic factors. Although early nonblinded and uncontrolled studies showed promising outcomes, some later double-blinded, randomized, and controlled trials have been less effective than anticipated. 3 More recently, cell therapy has been developed as a second angiogenic therapy. Initially, peripheral blood-derived or bone marrow-derived mononuclear cells (MNCs) were transplanted as endothelial progenitor cells, which should ...

Bioprinting with pre-cultured cellular constructs towards tissue engineering of hierarchical tissues

“…In this technique, a micro-scaled surface patterning technique with biofunctional materials and transfer cell printing technique were applied. We also confirmed that the engineered capillary-like structures were able to function as capillary vessels after implantation into experimental animals [16] . We concluded that this approach of applying a combination of bio-patterning and transfer cell printing techniques has big potential for engineering not only capillary vessels, but also various types of tissue components.…”

Amniotic Membrane Scaffolds Enable the Development of Tissue-Engineered Urothelium with Molecular and Ultrastructural Properties Comparable to that of Native Urothelium

“…42 Furthermore, Resch et al 43 demonstrated that the stroma of the transplanted AM can integrate into the host corneal tissue. Recently, the AM was also used as a scaffold for the engineering of the capillary structure by printing technology, 44 suggesting that the AM, which is primary avascular tissue, could also be vascularized. All these promising findings illustrate the behavior of AM scaffolds in vivo and thereby set the promising background for the potential use of our highly differentiated tissue constructs in reconstructive urology.…”

Printing a Tissue

“…10 Currently, an important tissue engineering strategy for the vascular and cardiac regeneration may be cell sheet technology, using either a temperature-responsive polymer or magnetic cell arrangement methods. 8,11,12 Clearly, the tissue printing method demonstrated herein by Yoshida et al 6 is an additional strategy for tissue engineering. For future clinical application, there may be several issues to be further studied.…”

“…In fact, direct implantation of adiposederived regenerative cells has been shown to stimulate angiogenesis and to mobilize endothelial progenitor cells in the setting of tissue ischemia. 5 In this issue of Arteriosclerosis, Thrombosis, and Vascular Biology, Yoshida et al 6 report that implantation of human omentum adipose tissue-derived microvascular endothelial cells (HOMECs) augmented angiogenesis in a mouse model of hindlimb ischemia. Moreover, a unique and new aspect of their research is that they used an engineered endothelial capillary network based on optical lithographic printing technique.…”

“…However, they overcame this issue using sphingosine 1-phosphate, which facilitated the capillary structure formation via the sphingosine 1-phosphate 2 receptor-Rho kinase-ROCK pathway. 6 Tissue engineering techniques are emerging because coordinated cell and scaffold structure is sometimes more effective than single-cell injection. For example, mesenchymal stem cell or skeletal myoblast cell sheet implantation has been shown to improve cardiac function in severe ischemic cardiomyopathy, 8,9 but such efficacies were not confirmed in the case of the single-cell injection technique.…”