Clinical assessment after human adipose stem cell transplantation into dogs

Abstract

Adipose tissue-derived stem cell (ASCs) are an attractive source of stem cells with therapeutic applicability in various fields for regenerating damaged tissues because of their stemness characteristics. However, little has reported on evaluating adverse responses caused by human ASC therapy. Therefore, in the present study, a clinical assessment after human ASC transplantation into dogs was undertaken. A total of 12 healthy male dogs were selected and divided into four groups: saline infusion, saline bolus, ASC infusion, and ASC bolus groups. Physical assessment and blood analysis were performed following ASC transplantation, and the concentrations of angiogenic factors, and pro- and anti-inflammatory cytokines were measured by enzyme-linked immunosorbent assay (ELISA). There were no adverse vital sign responses among the dogs. Blood analyses revealed no remarkable complete blood count or serum chemistry results. ELISA results for angiogenic and anti-inflammatory factors including matrix metalloproteinase 9 (MMP9), vascular endothelial growth factor (VEGF), basic fibroblast growth factor (bFGF), hepatocyte growth factor (HGF), and interleukin-10 (IL-10) were significantly higher in the two ASCs groups than in the controls. In conclusion, this study demonstrated that transplantation of human ASCs produced no adverse effects and could be used safely in dogs. In addition, human ASCs could be involved in modulating secretions of angiogenic factors including MMP9, VEGF, bFGF, and HGF and anti-inflammatory factor IL-10.

Keywords: adipose stem cells; angiogenic factors; anti-inflammatory factor; dogs; transplantation.

Fig. 1. Assessment of (A) heart rate (normal range, 60–180 beats/min), (B) body temperature (normal range, 37.7℃–39.1℃), and (C) respiratory rate (normal range, 10–35 breaths/min) after the saline or adipose tissue-derived stem cell (ASC) transplantation. No significant differences in vital signs among the four groups (p > 0.05) and all groups were within normal ranges. 0, 5, 10, 15, 20, 25, 30 min: time after saline or ASC transplantation (infusion rate, 3 mL/min; bolus rate, 60 mL/min).

Fig. 2. Physical examination outcomes. (A) Representative lead II electrocardiography (ECG) tracing recorded from a member of each group (saline infusion, saline bolus, adipose tissue-derived stem cells [ASCs] infusion, and ASCs bolus) after transplantation of saline of ASCs. (B) Observation of limb swelling in representatives of each group after transplantation of saline or ASCs. (C) Physical examination outcome for heart murmur and neurological symptom. For evaluation of neurological symptom, cranial nerve reflexes and postural reflexes were examined. NE, none exist.

Fig. 3. Evaluation of complete blood cell count after saline or adipose tissue-derived stem cell (ASC) transplantation. All groups were within normal ranges. 1, 7, 14, 21, 28 days: time after the saline or ASC transplantation (infusion rate, 3 mL/min; bolus rate, 60 mL/min). Each group had 3 dogs and an analysis was performed on days 1, 7, 14, 21, and 28 post-transplantation in each dog. WBC, white blood cell; RBC, red blood cell; PLT, platelet; PCV, packed cell volume; HB, hemoglobin; BASO, basophil; EOS, eosinophil; NEUT, neutrophil.

Fig. 4. Evaluation of serum chemistry analysis after the saline or adipose tissue-derived stem cell (ASC) transplantation. ^a,bWithin groups, values with different superscript letters are significantly different (p < 0.05) and all groups were within normal ranges. 1, 7, 14, 21, 28 days: time after the saline or ASC transplantation (infusion rate, 3 mL/min; bolus rate, 60 mL/min). Each group had 3 dogs and an analysis was performed on days 1, 7, 14, 21, and 28 post-transplantation in each dog. Na, sodium; K, potassium; Cl, chloride; ALP, alkaline phosphatase; ALT, alanine aminotransferase; AST, aspartate aminotransferase; CREA, creatinine; BUN/UREA, blood urea nitrogen/urea; Ca, calcium; P, phosphorus.

Fig. 5. Concentration of matrix metalloproteinase 9 (MMP9), vascular endothelial growth factor (VEGF), basic fibroblast growth factor (bFGF), hepatocyte growth factor (HGF), tumor necrosis factor (TNF)-α, and interleukin-10 (IL-10) from serum in each group after the saline or adipose tissue-derived stem cell (ASC) transplantation. ^a,b,cWithin groups, values with different superscript letters are significantly different (p < 0.05). 1, 7, 14, 21, 28 days: time after the saline or ASCs transplantation (infusion rate: 3 mL/min, bolus rate: 60 mL/min). Each group had 3 dogs and an analysis was performed on days 1, 7, 14, 21, 28 post-transplantation in each dog.