Effect of needle diameter on the viability of equine bone marrow derived mesenchymal stem cells.
Authors: Lang Hayley M, Schnabel Lauren V, Cassano Jennifer M, Fortier Lisa A
Journal: Veterinary surgery : VS
Summary
# Editorial Summary: Needle Gauge and Equine Mesenchymal Stem Cell Viability When administering bone marrow-derived mesenchymal stem cells (MSCs) for musculoskeletal repair, the mechanical stress imposed during needle passage can substantially compromise cell viability—a critical consideration that has received limited investigation until now. Researchers from Cornell University evaluated this effect by passing equine MSCs through needles of varying gauges (20, 22, 23, and 25-gauge) multiple times to simulate clinical preparation and injection procedures, measuring cell viability via flow cytometry after samples had been held at room temperature for 7 hours to approximate shipping conditions. MSCs aspirated through 20-gauge needles demonstrated significantly higher viability than those passed through 25-gauge needles, with the larger-gauge samples also containing proportionally more intact cells and less cellular debris; whilst neither individual horse nor cell passage number materially influenced outcomes, the trend toward increased debris with smaller needle diameters was evident. The mechanical trauma of smaller-gauge needles appears to compromise membrane integrity and cell function, directly affecting the therapeutic potential of injected cell populations. Practitioners should therefore preferentially use 20-gauge needles or larger when administering MSCs, as this relatively straightforward adjustment can meaningfully preserve the biological activity of these expensive and labour-intensive cell preparations before clinical delivery.
Read the full abstract on PubMed
Practical Takeaways
- •When injecting stem cells clinically, use larger gauge needles (20-ga or larger) rather than smaller gauges (25-ga) to preserve cell viability and treatment efficacy
- •The needle diameter used during cell resuspension and injection directly impacts how many viable cells actually reach the target tissue—use the largest practical needle size for your injection site
- •Cell damage from needle trauma is cumulative with smaller gauges, so standardize on 20-ga needles when preparing stem cell suspensions for injection
Key Findings
- •MSC viability was significantly higher when cells passed through 20-gauge needles compared to 25-gauge needles
- •20-gauge needle samples contained a larger percentage of intact cells with less cellular debris than 25-gauge samples
- •Cell debris percentage increased with decreasing needle diameter (inverse relationship)
- •Neither horse source nor cell passage number significantly affected viability outcomes