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Injectable pre-cultured tissue modules catalyze the formation of extensive functional microvasculature in vivo.

ABSTRACT: Revascularization of ischemic tissues is a major barrier to restoring tissue function in many pathologies. Delivery of pro-angiogenic factors has shown some benefit, but it is difficult to recapitulate the complex set of factors required to form stable vasculature. Cell-based therapies and pre-vascularized tissues have shown promise, but the former require time for vascular assembly in situ while the latter require invasive surgery to implant vascularized scaffolds. Here, we developed cell-laden fibrin microbeads that can be pre-cultured to form primitive vascular networks within the modular structures. These microbeads can be delivered in a minimally invasive manner and form functional microvasculature in vivo. Microbeads containing endothelial cells and stromal fibroblasts were pre-cultured for 3 days in vitro and then injected within a fibrin matrix into subcutaneous pockets on the dorsal flanks of SCID mice. Vessels deployed from these pre-cultured microbeads formed functional connections to host vasculature within 3 days and exhibited extensive, mature vessel coverage after 7 days in vivo. Cellular microbeads showed vascularization potential comparable to bulk cellular hydrogels in this pilot study. Furthermore, our findings highlight some potentially advantageous characteristics of pre-cultured microbeads, such as volume preservation and vascular network distribution, which may be beneficial for treating ischemic diseases.

SUBMITTER: Friend NE

PROVIDER: S-EPMC7511337 | biostudies-literature | 2020 Sep

REPOSITORIES: biostudies-literature

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Injectable pre-cultured tissue modules catalyze the formation of extensive functional microvasculature in vivo.

Friend Nicole E NE Rioja Ana Y AY Kong Yen P YP Beamish Jeffrey A JA Hong Xiaowei X Habif Julia C JC Bezenah Jonathan R JR Deng Cheri X CX Stegemann Jan P JP Putnam Andrew J AJ

Scientific reports 20200923 1

Revascularization of ischemic tissues is a major barrier to restoring tissue function in many pathologies. Delivery of pro-angiogenic factors has shown some benefit, but it is difficult to recapitulate the complex set of factors required to form stable vasculature. Cell-based therapies and pre-vascularized tissues have shown promise, but the former require time for vascular assembly in situ while the latter require invasive surgery to implant vascularized scaffolds. Here, we developed cell-laden ...[more]

PMID: 32968145

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Injectable pre-cultured tissue modules catalyze the formation of extensive functional microvasculature in vivo.

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Injectable pre-cultured tissue modules catalyze the formation of extensive functional microvasculature in vivo.

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