Effect of Needle Diameter and Flow Rate on Mesenchymal Stromal Cell (MSC) Cell Characterization and Viability

Abstract

Introduction: Current mesenchymal stromal cell (MSC) delivery methods require infusion/implantation through needles and/or catheters. Little investigation into the effect of delivery via catheter injection has been completed. We hypothesize that injection of MSCs through various clinically relevant catheters and flow rates will not affect cell viability, characterization, or function. Methods: MSCs were injected through 20, 25, and 30 gauge needles, as well through an SL-10 microcatheter at rates of 60, 120, 240, and 500 ml/hr (n=4/group). MSC viability and apoptotic fraction was measured. MSCs were characterized 24 hours after injection with flow cytometric immunophenotyping. Multilineage differentiation was also completed. Results: Catheter diameter or flow rate did not affect MSC viability. A decrease in apoptotic fraction (2.95%) (p=0.0011) was observed for the SL-10 microcatheter only. No difference in the surface markers CD11b, CD45, CD29, CD49e, CD73, CD90, CD105, and Stro-1 or the capacity for multilineage differentiation (adipogenesis, osteogenesis, and chondrogenesis) was observed. Conclusion: The injection of MSCs through various clinically relevant catheters and flow rates did not have a clinically significant effect on viability, characterization, or function. These results indicate that commonly used methods of cell delivery do not significantly impact MSCs.