Autologous Fractionated Adipose Tissue as a Natural Biomaterial and Novel One-Step Stem Cell Therapy for Repairing Articular Cartilage Defects

Abstract

Articular cartilage damage remains a tough challenge for clinicians. Stem cells have emerged promising biologics in regenerative medicine. Previous research has widely demonstrated that adipose-derived mesenchymal stem cells (ADSCs) can promote cartilage repair due to their multipotency. However, enzymatic isolation and monolayer expansion of ADSCs decrease their differentiation potential and limit their clinical application. Here, a novel adipose tissue-derived product, extracellular matrix/stromal vascular fraction gel (ECM/SVF-gel), was obtained by simple mechanical shifting and centrifugation to separate the fat oil and concentrate the effective constituents. This study aimed to evaluate the therapeutic effect of this natural biomaterial on the repair of articular cartilage defects. Scanning electron microscopy showed that the fibrous structure in the ECM/SVF-gel was preserved. ADSCs sprouted from the ECM/SVFgel were characterized by their ability of differentiation into chondrocytes, osteoblasts, and adipocytes. In a rabbit model, critical-sized cartilage defects (diameter, 4 mm; depth, 1.5 mm) were created and treated with microfracture (MF) or a combination of autologous ECM/SVF-gel injection. The knee joints were evaluated at 6 and 12 weeks through magnetic resonance imaging, macroscopic observation, histology, and immunohistochemistry. The International Cartilage Repair Society score and histological score were significantly higher in the ECM/SVF-gel group than those in the MFtreated group. The ECM/SVF-gel distinctly improved cartilage regeneration, integration with surrounding normal cartilage, and the expression of hyaline cartilage marker, type II collagen, in comparison with the MF treatment alone. Overall, the ready-touse ECM/SVF-gel is a promising therapeutic strategy to facilitate articular cartilage regeneration. Moreover, due to the simple, time-sparing, cost-effective, enzyme-free, and minimally invasive preparation process, this gel provides a valuable alternative to stem cell-based therapy for clinical translation.

Strategies to Convert Cells into Hyaline Cartilage: Magic Spells for Adult Stem Cells

“…Recently, a strategy was proposed to simplify the cell therapy procedure and remove steps associated with the enzymatic isolation, cell expansion and scaffold fabrication. Autologous fractionated adipose tissue (so-called ECM/SVF-gel in the study), a gel-like substance consisting of adipose tissues mechanically destroyed by simple mechanical shifting between two syringes, was applied to cartilage injury repair in combination with a microfracture in a rabbit model [ 134 ]. Twelve weeks after the ECM/SVF-gel injection, the knee joints were evaluated using MRI, macroscopic observation, histology and IHC.…”

Adipose Stem Cells in Regenerative Medicine: Looking Forward

“…Another study by Pers and others demonstrated that patients who received autologous ASCs injections in the knee showed improvement due to the paracrine factors released from the cells inducing an anti-inflammatory response ( Pers et al, 2018 ). A recent study conducted by Li and others described the use of ECM/SVF-gel fraction in cartilage defect repair as ASCs migrate from the gel and differentiate in a natural microenvironment, thus increasing the therapeutic potential of ASCs ( Li et al, 2020 ). Furthermore, engineered cartilage is another area that is gaining interest, as ASCs and Poly ε-Caprolactone Scaffolds have successfully been used to regenerate cartilage in vitro for later transplantation into a mouse model ( Nguyen and Vu, 2021 ).…”

The Mechanistic Effects and Clinical Applications of Various Derived Mesenchymal Stem Cells in Immune Thrombocytopenia

“…Nonetheless, this study has provided insight into the role of ASCs in ITP. ASCs are easily attached to plastic culture bottles and expanded in vitro [63]. These cells can also differentiate into multiple cell lines and thus have the potential to repair, maintain, or strengthen various tissues.…”