Injection of Porcine Adipose Tissue-Derived Stromal Cells by a Novel Waterjet Technology

Abstract

Previously, we developed a novel, needle-free waterjet (WJ) technology capable of injecting viable cells by visual guided cystoscopy in the urethral sphincter. In the present study, we aimed to investigate the effect of WJ technology on cell viability, surface markers, differentiation and attachment capabilities, and biomechanical features. Porcine adipose tissue-derived stromal cells (pADSCs) were isolated, expanded, and injected by WJ technology. Cell attachment assays were employed to investigate cell–matrix interactions. Cell surface molecules were analyzed by flow cytometry. Cells injected by Williams Needle (WN), normal cannula, or not injected cells served as controls. Biomechanical properties were assessed by atomic force microscopy (AFM). pADSCs injected by the WJ were viable (85.9%), proliferated well, and maintained their in vitro adipogenic and osteogenic differentiation capacities. The attachment of pADSCs was not affected by WJ injection and no major changes were noted for cell surface markers. AFM measurements yielded a significant reduction of cellular stiffness after WJ injections (p < 0.001). WJ cell delivery satisfies several key considerations required in a clinical context, including the fast, simple, and reproducible delivery of viable cells. However, the optimization of the WJ device may be necessary to further reduce the effects on the biomechanical properties of cells.

Isolation and characterization of farm pig adipose tissue-derived mesenchymal stromal/stem cells

“…The percentage of farm pASCs marked by CD29 and CD90 was higher than 95%, while CD45 and CD31 was lower than 0.5%. These results also characterize the farm pASCs as being cells of the mesenchymal type since they present cell surface antibodies typical of this cell type ( 3 , 27 - 34 ).…”

“…The pASCs immunophenotype analysis was performed with cells at passage 3 by flow cytometry in a FACSCalibur flow cytometer (USA). The choice of antibodies was based on the recommendations of the International Society of Cellular Therapy (ISCT) and the International Federation for Adipose Therapeutics and Science (IFATS) ( 13 , 14 ), and their use has been reported in several studies for the characterization of this cell type ( 3 , 27 - 34 ). Cells were incubated, separately, with purified antibodies CD29 (1:2000, 552369, BD Biosciences) and CD90 (1:2000, 555593, BD Biosciences), and primary antibodies CD45 (340943, BD Biosciences) and CD31 (555027, BD Biosciences) for 30 min at 4°C.…”

Novel Techniques to Improve Precise Cell Injection

“…However, at higher pressures and therefore at faster travel speed, cell viability decreases after injection through narrow tubes, and especially through pipes with nozzles (Figures 1 and 2). For successful injection of viable cells in a tissue, therefore, an upgraded pump and controller system (UPaCS) operating at two distinct pressure levels and an improved pressure control mode (IPCM) were developed (Figures 8 and 9A) [41][42][43]. This system allows cell administration into the sphincter muscular layer by a two-phase injection (Figure 8C).…”

Replacing Needle Injection by a Novel Waterjet Technology Grants Improved Muscle Cell Delivery in Target Tissues

“…Deposition of cells at suboptimal sites or even loss of cells by full penetration of the needle through the delicate urethral sphincter may in part explain the contradictory situation in reports on SUI cell therapy 10 . To improve precision of cell injection in the urethral sphincter, we developed a novel waterjet (WJ) technology and used primarily ADSCs 20 – 22 . By this novel technology, cells ride gently in a stream of an isotonic buffer less than 200 μm wide and, if needed, enriched by bioactive molecules such as growth factors or by components facilitating attachment of cells to the injection side 20 , 21 .…”