Life science
Medical care, Regenerative therapy

Development of novel administration method to improve regenerative
capacity of cell therapy in peripheral artery disease
Department of Cardiovascular Surgery, Graduate School of Medicine
Assistant Professor Keisuke Miyake

https://researchmap.jp/k-miyake

Professor Shigeru Miyagawa

https://researchmap.jp/s-miyagawa3154

Life science

Abstract
Peripheral artery disease (PAD) is a global problem because of
the growing number of patients and the dreadful outcome of thedisease with high major amputation rate and subsequent poor
survival outcome. Although revascularization is the standard treatment for PAD, growing number of patients are difficult to treat withstandard treatment, and alternative ways of treatment, including
regenerative cell or gene therapy, have been pursued. However,
severe ischemic and inflammatory condition of the disease limits
the treatment efficacy of such regenerative treatment because administered agents cannot survive sufficient to show treatment effectin such harsh environment, and therefore current guideline does
not recommend regenerative therapy for PAD due to the scarcetreatment efficacy. In this study, we developed a novel administration method of cells, in which cells are combined with extracellularmatrices to form “clustered cells.” Clustered cells dramatically
improved cell survival even in a severe ischemic and inflammatory
condition, and consequently showed improved regenerative effectby controlling inflammatory condition and augmenting angiogenesis and muscle regeneration.

▍ Significance of the research and Future perspective
This study showed the therapeutic effect of novel administration
method of cells in the form of clustered cells. Clustered cell administration enabled to improve administered cell survival, which
in turn enabled to control inflammation and to promote tissue regeneration. This study suggested that clustered cell administration
would enable to bring therapeutic effects in various inflammatory
and/or ischemic diseases that are refractory to cell therapy so far.

▍ Background & Results
The low survival rate of administered agents due to severe ischemic and inflammatory environments limits the efficacy of thecurrent regenerative therapy in peripheral artery disease (PAD).
We previously clarified the efficacy of cell sheet technology for ischemic cardiomyopathy by improving cell retention rate. This study
aimed to develop a new treatment method to enhance the efficacy
of cell therapy in PAD with severe ischemic and inflammatory environments, using cell sheet technology. Clustered cells from myoblast cell sheets obtained from mice, which included various extracellular matrices, including laminin, fibronectin, and vitronectin,were administered into ischemic mouse muscles. A chronic severe
limb ischemia model was developed to mimic PAD ischemic condition. Control groups were administered with single myoblast cells
or saline. Compared with the single cell administration, clusteredcells showed markedly improved cell survival at 7 days and 28
days after administration. Consequently, clustered cells administration alone showed markedly improved blood perfusion of the limb,
angiogenesis, and muscle regeneration, along with the upregulation of associated genes. Additionally, inflammation status was wellregulated by clustered cells administration. Clustered cells administration increased the number of macrophages and then induced
polarization into an anti-inflammatory phenotype, along with theincreased expression of genes associated with anti-inflammatory
cytokines. Our findings suggested clinical potential of rescuing severely damaged limbs in PAD using clustered cells.

P a t e n t Japanese Patent No. 2019-203477, WO2021090945A1
Miyake, Keisuke; Miyagawa, Shigeru; Sawa, Yoshiki et al. Engineered clustered myoblast cell injection augments angiogenesis and muscle regeneration
Tr e a t i s e
in peripheral artery disease. Mol Ther. 2022, 30 (3), p. 1239-1251, doi: 10.1016/j.ymthe.2022.01.008
URL
K e y w o r d cell therapy, peripheral artery disease, angiogenesis, chronic inflammation