Evaluation of the Usefulness of Human Adipose-Derived Stem Cell Spheroids Formed Using SphereRing® and the Lethal Damage Sensitivity to Synovial Fluid In Vitro

Abstract

Osteoarthritis (OA) is an irreversible degenerative condition causing bone deformation in the joints and articular cartilage degeneration with chronic pain and impaired movement. Adipose-derived stem cell (ADSC) or crushed adipose tissue injection into the joint cavity reportedly improve knee function and symptoms, including pain. Stem cell spheroids may be promising treatment options due to their anti-inflammatory and enhanced tissue regeneration/repair effects. Herein, to form human ADSC spheroids, we used first SphereRing® (Fukoku Co., Ltd., Ageo, Japan), a newly developed rotating donut-shaped tube and determined their characteristics by DNA microarray of mRNA analysis. The variable gene expression cluster was then identified and validated by RT-PCR. Gene expression fluctuations were observed, such as COL15A1 and ANGPTL2, related to vascular endothelial cells and angiogenesis, and TNC, involved in tissue formation. In addition, multiplex cytokine analysis in the medium revealed significant cytokines and growth factors production increase of IL-6, IL-10, etc. However, ADSC administration into the joint cavity involves their contact with the synovial fluid (SF). Therefore, we examined how SF collected from OA patient joint cavities affect 2D-culture ADSCs and ADSC spheroids and observed SF induced cell death. ADSC spheroids could become promising OA treatment options, although studying the administration methods and consider their interaction with SF is essential.

A novel cell source for therapy of knee osteoarthritis using atelocollagen microsphere-adhered adipose-derived stem cells: Impact of synovial fluid exposure on cell activity

“…On the other hand, ADSCs possess a high immunoregulatory capacity as a result of their secretion of immunomodulatory and growth factors [ 39 ]. In a previous study, we generated ADSC spheroids using a specialized culture device and demonstrated an increased secretion of the representative anti-inflammatory cytokine IL-10 compared with 2D cultures [ 28 ]. IL-10 has inhibitory effects on intra-articular inflammation in patients with knee OA [ 40 , 41 ].…”

“…3 ). Cytokine secretion by ADSCs is influenced by variations in the culture environment, with hypoxic conditions and spheroid cultures promoting IL-10 secretion by ADSCs [ 28 , 40 , 42 ]. Therefore, it is suggested that stirred culture with AMS-adherent ADSCs may also impact the ability of ADSCs to secrete IL-10.…”

“…Following approval by the Ethics Review Committee of Kanazawa Medical School (approval number I583), SF was collected from the knee joints of patients with knee OA (Kellgren–Laurence [K–L] classification Grades 2–3) according to previous reports [ 27 , 28 ]. All patients provided informed consent prior to SF collection.…”

Advancements in culture technology of adipose-derived stromal/stem cells: implications for diabetes and its complications

“…The study illustrated the stimulatory impact of spheroid formation on ASCs towards endothelial lineage by observing increased expression of cluster of differentiation (CD) 31, which persisted following the seeding of ASC spheroids on cell sheets. Furthermore, compared to ASC sheets, ASC spheroid sheets exhibited heightened expression of VEGF and HGF, and the conditioned medium from ASC spheroid sheets significantly promoted tube formation of endothelial cells in vitro (136).…”