Rationale and Design of Therapeutic Angiogenesis by Cell Transplantation Using Adipose-Derived Regenerative Cells in Patients With Critical Limb Ischemia - TACT-ADRC Multicenter Trial

Therapeutic angiogenesis for patients with no-option critical limb ischemia by adipose-derived regenerative cells: TACT-ADRC multicenter trial

Background

Patients with critical limb ischemia (CLI) still have a high rate of lower limb amputation, which is associated with not only a decrease in quality of life but also poor life prognosis. Implantation of adipose-derived regenerative cells (ADRCs) has an angiogenic potential for patients with limb ischemia.

Objectives

We investigated safety, feasibility, and efficacy of therapeutic angiogenesis by cell transplantation (TACT) of ADRCs for those patients in multicenter clinical trial in Japan.

Methods

The TACT-ADRC multicenter trial is a prospective, interventional, open-labeled study. Patients with CLI (Fontaine class III–IV) who have no other option for standard revascularization therapy were enrolled in this study. Thirty-four target ischemic limbs of 29 patients were received freshly isolated autologous ADRCs implantation.

Results

The overall survival rate at a post-operative period and at 6 months follow-up was 100% at any time points. As a primary endpoint for efficacy evaluation, 32 limbs out of 34 (94.1%) were free from major amputation for 6 months. Numerical rating scale (from 6 to 1) as QOL score, ulcer size (from 317 mm² at to 109 mm²), and 6-min walking distance (from 255 to 369 m) improved in 90.6%, 83.3%, and 72.2% patients, respectively.

Conclusions

Implantation of autologous ADRCs could be safe and effective for the achievement of therapeutic angiogenesis in the multicenter settings, as a result in no major adverse event, optimal survival rate, and limb salvage for patients with no-conventional option against critical limb ischemia.

TRN: jRCTb040190118; Date: Nov. 24th, 2015.

Supplementary Information

The online version contains supplementary material available at 10.1007/s10456-022-09844-7.

Adipose-derived regenerative cells as a promising therapy for cardiovascular diseases: an overview

The number of patients with ischemic cardiovascular diseases is significantly increasing as populations age. Therapeutic angiogenesis has been developed as a new treatment strategy for such patients. In recent years, the presence of mesenchymal stem cells in adipose tissues was reported, and regenerative medicine using these cells has attracted attention worldwide. In this review, we describe how the transplantation of adipose-derived regenerative cells enhances angiogenesis and tissue regeneration because of their multilineage potential and cytokine secretion. Then, the current status of therapeutic angiogenesis using adipose-derived regenerative cells in the field of cardiovascular medicine was also described. These cells present great advantages over bone marrow mononuclear cells, as these need easier, shorter, and less invasive preparations as well as less ethical concerns and immunological problems. The efficacy of adipose-derived regenerative cell transplantation in the treatment of various diseases was examined in several clinical trials with favorable results. Currently, a multicenter study of therapeutic angiogenesis using these cells is being conducted in patients with critical limb ischemia. In conclusion, we expect that this method will soon be established as a treatment for cardiovascular diseases that have been refractory to conventional treatments.

No influence on tumor growth by intramuscular injection of adipose-derived regenerative cells: safety evaluation of therapeutic angiogenesis with cell therapy

Therapeutic angiogenesis with autologous stem/progenitor cells is a promising novel strategy for treatment of severe ischemic diseases. Human clinical trials utilizing autologous adipose-derived regenerative cells (ADRCs) have not reported treatment-related critical adverse effects thus far. However, there is still a large knowledge gap regarding whether treatment of ischemic diseases with angiogenic therapy using ADRCs would promote unfavorable angiogenesis associated with tumors in vivo. Herein, we addressed this clinical question using a mouse hindlimb ischemia (HLI) and simultaneous remote tumor implantation model. C57BL/6J background wild-type mice were injected with murine B16F10 melanoma cells on their back, 1 day before ischemic surgery. These mice were subjected to surgical unilateral hindlimb ischemia, followed by ADRC implantation or PBS injection into the hindlimb ischemic muscles on the next day. Intramuscular implantation of ADRCs enhanced tissue capillary density and blood flow examined by a laser Doppler blood perfusion analysis in hind limb. However, this therapeutic regimen for ischemic limb using ADRCs did not affect remote melanoma growth nor the density of its feeder artery, angiogenesis, and lymphatic vessels compared with the PBS group. In addition, no distant metastases were detected in any of the mice regardless of the group. In conclusion, local implantation of ADRCs promotes angiogenesis in response to tissue ischemia in the hindlimb without promoting remote tumor growth and related angio/lymphangiogenesis. Therapeutic angiogenesis to the ischemic hindlimb using ADRCs seems to be safe regarding remote tumor growth.NEW & NOTEWORTHY In this study, we demonstrated that local injection of ADRCs can promote angiogenesis in response to tissue ischemia without promoting remote tumor growth in a mouse model. Our findings indicate that therapeutic angiogenesis to the ischemic hindlimb using ADRCs seems to be safe regarding remote tumor growth.