Physiology meets regenerative medicine & education becomes research: using muscle force production to assess ischemia and arteriogenesis in a masters‐level cell transplantation laboratory
Authors: Cardinal Trevor R 
Published: November 2023

Mice are the most common model in biomedical research, and are often the final preclinical platform for evaluating gene, protein, and cell‐based therapies before human trials. Considering their widespread use in basic investigation and their emerging importance in bio‐therapeutic product development, we implemented a cell transplantation course to educate students in surgery and physiological measurements in mice; the course is required for students in our MS Specialization in Regenerative Medicine and is an elective for other BS and MS students. The original goals of the course were to provide students experience in animal handling and anesthesia, aseptic surgery, and physiological measurements.

To accomplish these goals, up to 24 students perform femoral artery ligation surgeries to produce a mouse model of chronic peripheral ischemia (2 surgeries per student). At the time of surgery, collagen gels, collagen gels containing 3T3 fibroblasts, or nothing was implanted deep to the gracilis anterior muscle, which contains the primary collaterals perfusing the downstream ischemic tissue. Seven days after surgery, students measured in vivo twitch forces in the gastrocnemius + soleus via sciatic nerve stimulation to determine the impact of ischemia, and any endogenous arteriogenic compensation, on muscle performance, and the effectiveness of the cell transplantation therapy. As stated, the original goal was to provide students experience with skills related to animal experimentation; we didn't expect students to collect consistent data, given the complexity of the procedures, the small number of replicates per student, and the heterogeneity among novices in this early training period. However, after refining both the training procedures and the experimental protocols over the first several offerings of the course, we began to compile the class‐wide data.

Surprisingly, the students collected data that was consistent enough to capture both subtle and overt differences between groups. First, students found that the control limb in all experimental groups was not a true control, as it produced a lower maximimum twitch force than un‐operated animals (mN/mg for all results)‐ 1.28 ± 0.24 (sham collagen), 1.44 ± 0.29 (collagen), and 1.44 ± 0.19 (collagen + fibroblasts) versus 1.55 ± 0.31 (un‐operated), p < 0.05. Additionally, as expected, the femoral artery ligation reduced the maximum twitch force‐ 0.23 ± 0.02 (p < 0.05 vs all control groups). Interestingly, collagen implanted deep to the primary collaterals partially rescued maximum twitch force, 1.14 ± 0.20 (p < 0.05 vs ligation), but any therapeutic effect of fibroblasts + collagen was not captured due to high sample variability, 0.72 ± 0.46.

These results indicate the feasibility of collecting consistent physiological data from a clinically‐relevant mouse model in a course laboratory. This suggests that inquiry‐based laboratory experiences, which enhance students’ understanding of physiology, may also advance fundamental knowledge and test bio‐therapies. This paradigm, which is used in molecular biology, genomics, and bioinformatics courses, could increase the research productivity of academic institutions while enhancing students learning.

Support or Funding Information

CIRM‐ TB1‐01175