Introduction to a new cell transplantation platform via recombinant peptide petaloid pieces and its application to islet transplantation with mesenchymal stem cells

Cell death cluster in transplanted cells remains a critical obstacle for regeneration strategies. This study describes a novel platform for cell transplantation (CellSaic) consisting of human mesenchymal stem cells (hMSCs) and petaloid pieces of recombinant peptide (RCP), which can prevent cell death by arranging the cells in a mosaic. When hMSC CellSaics were subcutaneously implanted into NOD/SCID mice, hMSC CellSaics prevented cell death and accelerated angiogenesis in the graft, compared to the findings obtained on solely implanting cell spheroids. Additionally, we examined the application of CellSaic for subcutaneous cotransplantation of 200 rat islets with 2 × 10(5) hMSCs into diabetic mice. As the results of blood glucose levels at 1 m, the islet-only group was 398 ± 30 mg/dl and the islets with hMSCs group were 180 ± 65 mg/dl. On the other hand, the islets with hMSCs CellSaic group showed 129 ± 15 mg/dl and significantly improved glucose tolerance (P < 0.05). Additionally, we showed that the surface texture of the RCP petaloid pieces played an important role in graft survival and angiogenesis. It is anticipated that CellSaic will be used as a new platform for cell transplantation and tissue regeneration.

The Therapeutic Effects of Adipose-Derived Stem Cells and Recombinant Peptide Pieces on Mouse Model of DSS Colitis

Cell therapies using adipose-derived stem cells (ADSCs) have been used to treat inflammatory bowel disease (IBD) in human and dog. We previously reported the CellSaic technique, which uses a recombinant scaffold to enhance the efficacy of cell therapy. To examine whether this technique can be applied to cell therapy for colitis, we evaluated the efficacy of CellSaic in colitis mouse models. Colitis mouse models were developed by administering dextran sulfate sodium (DSS) to C57BL/6 mice for 7 days. Then CellSaic comprising human/canine ADSCs (1.2 × 10⁶ cells) or human/canine ADSCs only (1.2 × 10⁶ cells) were administered to the mice. The body weights were measured, and the colon length measurements and histological evaluations were conducted at 7 days after administration. After in vitro culture of human ADSC (hADSC) CellSaic and hADSC spheroids in medium containing TNFα, the levels of the anti-inflammatory protein TSG-6 in each supernatant were measured. Furthermore, we conducted tumorigenicity and general toxicity tests of canine ADSC (cADSC) CellSaic in NOG mice for 8 weeks. In the colitis mouse models, the ADSC CellSaic group presented recovery of body weight and colon length compared with the ADSC-only group. Histological analysis showed that ADSC CellSaic decreased the number of inflammatory cells and repaired ulceration. In vitro, hADSC CellSaic secreted 3.1-fold more TSG-6 than the hADSCs. In addition, tumorigenicity and general toxicity of cADSC CellSaic were not observed. This study suggests that human and canine ADSC CellSaic has a therapeutic effect of colitis in human and dogs.