Sarah Broeckx, Rudy Forier, Tom Mariën, Marc Suls, Vuk Savkovic, Alfredo Franco-Obregón, Luc Duchateau and Jan H Spaas
Background: It has been reported that mesenchymal stem cells (MSCs) have homing capacities after an intravenous injection and immuno modulating effects in vitro. However, there are no reports on their effect on the animal’s hematological status. Methods: Therefore, MSCs were isolated and characterized from a 4-years-old horse donor after having tested his blood on a wide range of transmittable diseases. Then, 6 horses (13- to 15-years-old) received a single injection into the jugular vein: 3 with MSCs and 3 with the carrier fluid consisting of DMEM and 10% of DMSO. Multiple blood samples were taken at different time points at the same time of the day: before the intravenous MSC (Veno-Cell®) injection ( T0) and 1 day (T1), 1 week (T2), 3 weeks (T3) and 2 months (T4) after the treatment. Results: In the control group no considerable changes were noticed over time, whereas, in all the treated horses, the baseline adjusted cortisol levels (P=0.0490) and number of neutrophils (P=0.0042) were significantly higher and glucose levels significantly lower (P=0.033). At time point T1, baseline adjusted blood thrombocyte levels were significantly higher in the treated group as compared to the control group (P<0.0001). On the other hand, baseline adjusted basophils, eosinophils, lymphocytes and monocytes remained approximately the same in all the horses regardless the treatment. Additionally, the levels of total protein, albumin, alkaline phosphatase and all the tested minerals were not influenced by the injections. Conclusion: In all patients consistent alterations in hematological parameters were noticed after intravenous allogenic MSC treatment. However, further research is warranted in order to verify what the exact influence of these changes might be on the animal’s metabolism, general condition and performance ability.