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Published on: September 23, 2022
Effect of needle diameter on the viability of equine bone marrow derived mesenchymal stem cells
Hayley M Lang1, Lauren V Schnabel1, Jennifer M Cassano1
1Department of Clinical Sciences, Cornell University, Ithaca, New York.
Objectives:
Mesenchymal stem cells (MSCs) are frequently delivered via needle injection for treatment of musculoskeletal injuries. The purpose of this study was to evaluate the effect of needle diameter on the viability of MSCs.
Methods:
Equine bone marrow-derived MSCs from 5 horses were suspended in PBS, and held at room temperature for 7 hours to mimic shipping conditions. Two replicate samples for each needle size (20, 22, 23, or 25-gauge [ga]) were aspirated into a 3 mL syringe and re-injected into the holding vial 3 times, to reproduce the resuspension of cells prior to injection in clinical cases. Cells were stained with fluorescein diacetate and propidium iodide to measure viability. Flow cytometry (FC) was performed to compare cell debris and intact cells between groups.
Results:
MSC viability was higher when cells were passed through a 20-ga rather than a 25-ga needle. Cell suspensions passed through a 20-ga needle contained a larger percentage of intact cells, compared to 25-ga samples. The percentage of debris present in cell suspensions tended to increase with decreasing needle diameter. Neither horse nor passage had a significant effect on viability.
Conclusions:
Cell damage is more likely when MSCs are passed through 25-ga rather than 20-ga needles.
Clinical Relevance:
Use of needles larger than 25-ga is recommended to maintain the viability of MSCs injected in horses.
Insights
Using larger needles, such as 20-gauge, preserves mesenchymal stem cell (MSC) viability better than smaller needles during injection for musculoskeletal injuries. Smaller needles, like 25-gauge, increase cell damage and debris.
Area of Science:
- Biomedical Engineering
- Regenerative Medicine
- Cell Biology
Background:
- Mesenchymal stem cells (MSCs) are crucial for treating musculoskeletal injuries.
- Current delivery methods often involve needle injection, potentially impacting cell viability.
Purpose of the Study:
- To investigate the impact of needle diameter on the viability of equine bone marrow-derived MSCs.
Main Methods:
- MSCs were subjected to simulated shipping conditions.
- Cells were passed through needles of varying gauges (20, 22, 23, 25-gauge) multiple times.
- Cell viability was assessed using fluorescein diacetate and propidium iodide staining, analyzed by flow cytometry.
Main Results:
- Higher MSC viability was observed with larger gauge needles (20-ga) compared to smaller ones (25-ga).
- Cell suspensions passed through 20-ga needles had a greater percentage of intact cells.
- Increasing needle gauge (decreasing diameter) correlated with increased cell debris.
Conclusions:
- Needle diameter significantly affects MSC viability, with smaller gauges causing more cell damage.
- Larger gauge needles (e.g., 20-ga) are recommended to maintain MSC viability for injection in horses.
