Intravenous injection of allogenic canine mesenchymal stem cells in 40 dogs: A safety assessment in veterinary clinical trials

This study aimed to evaluate the adverse effects of allogeneic mesenchymal stem cell (MSC) transplanted via intravenous infusion in dogs and examine their long-term safety, including tumorigenesis. This study conducted a retrospective analysis of various clinical assessments, including physical examination, blood tests, and radiographs, and monitored the formation of neoplasms during a 6-month follow-up period in 40 client-owned dogs that received intravenous infusion of adipose tissue-derived MSCs (AT-MSCs) for the treatment of various underlying diseases between 2012 and 2018. No significant adverse effects of MSC therapy were detected by clinical assessment, blood tests, or radiographic examination in the 6-month follow-up period after the first MSC treatment. Additionally no new neoplasms were observed during this period. This study is the first to evaluate the long-term (≥ 6 month) safety aspects and risk of tumorigenesis for intravenous allogenic AT-MSC infusion. These results suggest that allogenic AT-MSC infusion can be relatively safe therapeutic approach in dogs.