CTLA4 overexpressing adipose tissue-derived mesenchymal stem cell therapy in a dog with steroid-refractory pemphigus foliaceus.

BACKGROUND: Canine pemphigus foliaceus is an autoimmune antibody-mediated skin disease characterized by acantholysis. The objective of this case report is to present the successful management of steroid refractory pemphigus foliaceus with cytotoxic T-lymphocyte antigen 4 (CTLA4)-overexpressing adipose tissue mesenchymal stem cells (ATMSCs). CASE PRESENTATION: A 10-year-old, 12.3-kg, castrated male Shih Tzu presented with severe pruritus and anorexia. The diagnosis of pemphigus foliaceus was made based on its history, physical examination, and histopathology results of a skin biopsy. Treatment with prednisolone and combination therapy of other immunosuppressive drugs had failed; therefore, immunosuppressive gene, CTLA4 overexpressing ATMSCs (CTLA4-ATMSCs) and/or naive ATMSCs administration was performed with the consent of the owner. ATMSCs were administered 21 times over a period of 20 months with intervals of 2 to 8 week. Prednisolone was gradually tapered concurrently and no relapse of the clinical signs was observed. After the termination of CTLA4-ATMSCs and/or naive ATMSCs treatment, the skin lesions had improved and could be managed with a low dose of prednisolone for 12 months. CONCLUSION: CTLA4-ATMSCs or naive ATMSCs transplantation may be beneficial as adjunctive therapy to initiate and maintain the remission of skin lesions caused by pemphigus foliaceus in veterinary medicine.

Stimulatory effect of HGF-overexpressing adipose tissue-derived mesenchymal stem cells on thymus regeneration in a rat thymus involution model.

The thymus is the central lymphoid organ providing a unique and essential microenvironment for T-cell precursor development into mature functionally competent T-lymphocytes. Thus, it is important to develop the strategies for enhancing thymic regeneration from involution induced by a variety of clinical treatments and conditions. Hepatocyte growth factor (HGF) promotes proliferation in a variety of cell types. We have used stem cell-based HGF gene therapy to enhance regeneration from acute thymic involution. HGF-overexpressing human adipose tissue-derived mesenchymal stem cells (HGF-hATMSCs) were generated by liposomal transfection with the pMEX expression vector, constructed by inserting the HGF gene. Significantly increased HGF expression in these cells was confirmed by reverse transcription-polymerase chain reaction and an enzyme-linked immunosorbent assay. HGF produced by HGF-hATMSCs enhanced the proliferation of a mouse thymic epithelial cell line and the expression of interleukin-7 in vitro. We also examined the effect of HGF-hATMSCs on thymic regeneration in rats with acute thymic involution. Significant increases in thymus size and weight, as well as the number of thymocytes (especially, early thymocyte progenitors), were seen in the HGF-hATMSCs-treated rats compared to saline-treated control animals. A stimulatory effect of HGF-hATMSCs on thymic regeneration has therefore been shown, highlighting the clinical value of HGF-hATMSCs for treating thymic involution.

Effect of ectopic OCT4 expression on canine adipose tissue-derived mesenchymal stem cell proliferation.

Enhancing the proliferative capacity of mesenchymal stem cells (MSCs) is critical for increasing their therapeutic potential in a variety of diseases. We hypothesized that lentivirus-mediated overexpression of canine octamer-binding transcription factor 4 (OCT4) might influence the proliferation of canine adipose tissue-derived MSCs (cATMSCs). cOCT4-cATMSCs were generated by transducing cATMSCs with a cOCT4-lentiviral vector. Increased expression of cOCT4 was confirmed using RT-PCR and immunoblotting. Immunophenotypic characterization using flow cytometry indicated that the CD29, CD44, CD73, CD90, and CD105 surface markers were highly expressed by both cOCT4- and mock-transduced cATMSCs (mock-cATMSCs), whereas the CD31 and CD45 markers were absent. We performed the osteogenic differentiation assay to evaluate the effects of cOCT4 overexpression on the osteogenic differentiation potential of cATMSCs. The results showed that cOCT4-cATMSCs had a much higher potential for osteogenic differentiation than mock-cATMSCs. Next, the proliferative capacities of cOCT4- and mock-cATMSCs were evaluated using a WST-1 cell proliferation assay and trypan blue exclusion. cOCT4-cATMSCs showed a higher proliferative capacity than mock-cATMSCs. Cell cycle analysis indicated that overexpression of cOCT4 in cATMSCs induced an increase in the proportion of cells in S and G2/M phases. Consistent with this, immunoblot analysis showed that cyclin D1 expression was increased in cOCT4-cATMSCs. In conclusion, our results indicate that lentivirus-mediated overexpression of cOCT4 increased the proliferative capacity of cATMSCs. OCT4-mediated enhancement of cell proliferation may be a useful method for expanding MSC population rapidly without loss of stemness.

Predictive role of lactate in dogs with acute pancreatitis advanced to systemic inflammatory response syndrome.

Acute pancreatitis (AP) can develop into life-threatening conditions such as systemic inflammatory response syndrome (SIRS) or multiple organ dysfunction syndrome. Thirty-nine of 54 client-owned dogs admitted to the Referral Animal Medical Center and diagnosed with AP within 24 hr of onset were retrospectively reviewed to assess early predictors of progression from AP to SIRS. The patients were divided into SIRS (SIRS occurring after AP) and non-SIRS (AP occurring but no SIRS) groups. The population and mean values of laboratory variables within 24 hr of admission were assessed and compared between both groups. There were significantly more dogs with abnormal lactate levels in the SIRS group (80.00%) than non-SIRS group (11.10%). Other parameters did not differ significantly. Mean lactate level values were significantly higher at 3.64 ± 1.75 mmol in the SIRS group compared to 1.68 ± 0.52 mmol in the non-SIRS group. The increased energy required by activated immune cells may lead to metabolic changes characterized by anaerobic glycolysis and increased lactate production. This study's results suggest blood lactate monitoring in the early stages of progression from AP to SIRS in small animal clinical practice. Measuring lactate levels at the early stages of pancreatitis could lead to rapid therapeutic intervention for SIRS and ultimately reduce mortality.

Canine mesenchymal stem cells are effectively labeled with silica nanoparticles and unambiguously visualized in highly autofluorescent tissues.

BACKGROUND: Development of a method for long-term labeling of cells is critical to elucidate transplanted cell fate and migration as well as the contribution to tissue regeneration. Silica nanoparticles have been recently developed and demonstrated to be biocompatible with a high labeling capacity. Thus, our study was designed to assess the suitability of silica nanoparticles for labeling canine mesenchymal stem cells (MSCs) and the fluorescence afficiency in highly autofluorescent tissue. RESULTS: We examined the effect of silica nanoparticle labeling on stem cell morphology, viability and differentiation as compared with those of unlabeled control cells. After 4 h of incubation with silica nanoparticles, they were internalized by canine MSCs without a change in the morphology of cells compared with that of control cells. The viability and proliferation of MSCs labeled with silica nanoparticles were evaluated by a WST-1 assay and trypan blue exclusion. No effects on cell viability were observed, and the proliferation of canine MSCs was not inhibited during culture with silica nanoparticles. Furthermore, adipogenic and osteogenic differentiation of silica nanoparticle-labeled canine MSCs was at a similar level compared with that of unlabeled cells, indicating that silica nanoparticle labeling did not alter the differentiation capacity of canine MSCs. Silica nanoparticle-labeled canine MSCs were injected into the kidneys of BALB/c mice after celiotomy, and then the mice were sacrificed after 2 or 3 weeks. The localization of injected MSCs was closely examined in highly autofluorescent renal tissues. Histologically, canine MSCs were uniformly and completely labeled with silica nanoparticles, and were unambiguously imaged in histological sections. CONCLUSIONS: The results of the current study showed that silica nanoparticles are useful as an effective labeling marker for MSCs, which can elucidate the distribution and fate of transplanted MSCs.

Preventive and therapeutic effects of gene therapy using silica nanoparticles-binding of GM-CSF gene on white blood cell production in dogs with leukopenia.

OBJECTIVE: Our previous study has shown that granulocyte-macrophage colony-stimulating factor (GM-CSF) gene/silica nanoparticles have a leukocytosis effect in normal dogs. Therefore, this study was conducted to determine whether treatment of canine GM-CSF gene/silica nanoparticles has preventive or therapeutic effects in dogs with leukopenia. MATERIALS AND METHODS: To induce leukopenia, vinblastine was administered intravenously at a dose of 2 mg/m(2) of body surface area on day 0. Then 7.5 microg GM-CSF/nanoparticles (1:100, w/w) were administered intravenously to each of four dogs in the prevention group on day 2 and an equivalent amount of GM-CSF/nanoparticles was administered to the post-nadir group on day 4 (other groups were administered phosphate-buffered saline intravenously). RESULTS: Therapeutic GM-CSF gene was expressed in peripheral blood mononuclear cells for 10 days and both the prevention and post-nadir groups showed significant increases in white blood cell counts when compared with the control group, as confirmed by complete blood count, differential count, and flow cytometry. CONCLUSIONS: GM-CSF/nanoparticles can be useful for correction of acute leukopenia, such as chemotherapy-induced myelosuppression, without developing neutralizing antibodies.

Evaluation of nafamostat mesilate as an alternative anticoagulant during intermittent hemodialysis in healthy Beagle dogs.

OBJECTIVE: To evaluate nafamostat mesilate (NM) as an alternative anticoagulant agent for intermittent hemodialysis (IHD). DESIGN: Prospective randomized study. SETTING: University teaching hospital. ANIMALS: Eighteen healthy Beagle dogs. INTERVENTIONS: In group 1 (n = 6), NM was administered at a dose of 0.5 mg/kg/h during IHD for 5 hours. In group 2 (n = 6), NM was administered at a low dose of 0.25 mg/kg/h during IHD. In group 3 (n = 6), which was the control group, unfractionated heparin (UFH) was administered during IHD. The evaluated parameters included: the amount of residual blood clots in the blood chamber and arterial side of the dialyzer; the levels of hemoglobin, hematocrit, and platelets; and the prothrombin time (PT), activated partial thromboplastin time (aPTT), and activated clotting time (ACT). MEASUREMENTS AND MAIN RESULTS: Groups 1 and 2 successfully completed IHD without serious coagulation in the extracorporeal circulation. The residual blood clotting in the blood chamber and arterial side of the dialyzer did not significantly differ in groups 1 and 2 compared to group 3 (group 1 vs group 3, P = 1.000; and group 2 vs group 3, P = 1.000). No significant differences were observed between pre- and posttreatment PTs in groups 1 (P = 0.476) and 2 (P = 0.597), between pre- and posttreatment aPTTs in groups 1 (P = 0.983) and 2 (P = 0.977), and between pre- and posttreatment ACT in groups 1 (P = 0.282) and 2 (P = 0.401). In group 3, a significant elevation of ACT was observed at the posttest (P < 0.001). CONCLUSIONS: The results of this study in healthy Beagle dogs suggest that NM at 0.25 mg/kg/h may be a valid alternative to UFH for IHD. Further studies are needed in patients at high risk of bleeding.

Anti-inflammatory Effects of Oct4/Sox2-overexpressing Human Adipose Tissue-derived Mesenchymal Stem Cells.

BACKGROUND/AIM: The transcription factors Oct4 and Sox2 enhance the proliferation and pluripotency of human adipose tissue-derived mesenchymal stem cells (hAT-MSCs); however, the anti-inflammatory effects of Oct4- and Sox2-overexpressing hAT-MSCs (Oct4/Sox2-hAT-MSCs) are unclear. Here, we evaluated the anti-inflammatory effects of Oct4/Sox2-hAT-MSCs in vitro and in vivo. MATERIALS AND METHODS: Supernatants from green-fluorescent protein (GFP)- and Oct4/Sox2-hAT-MSCs were used to treat lipopolysaccharide (LPS)-stimulated RAW264.7 cells and inflammatory cytokine expression was determined. In LPS-induced mice, GFP- and Oct4/Sox2-hAT-MSCs were injected intraperitoneally and survival rates, as well as sickness scores of mice, were monitored. RESULTS: Decreased expression of pro-inflammatory cytokines was observed in Oct4/Sox2-hAT-MSC supernatant-exposed RAW264.7 cells compared to that in GFP-hAT-MSC supernatant-exposed RAW264.7 cells. The sickness score was reduced to 34.9% and the survival rate was increased by 11.1% in Oct4/Sox2-hAT-MSC-injected mice compared to that in GFP-hAT-MSC-injected mice. CONCLUSION: Our findings provide important insights into the development of therapies utilizing Oct4/Sox2-hAT-MSCs in inflammatory diseases.

Retrospective study of degenerative mitral valve disease in small-breed dogs: survival and prognostic variables.

Small-breed dogs (n = 168; weight ＜ 15 kg) diagnosed with myxomatous mitral valve degeneration based on a routine clinical examination, radiology, electrocardiography, and echocardiography at the Seoul National University Veterinary Medical Teaching Hospital were included in this study. Survival periods were determined, and there were significant differences in survival rates among the three International Small Animal Cardiac Health Council classes. The mean follow-up period was 14.3 ± 12.1 months. Univariate analysis revealed that dyspnea, pulmonary edema, and vertebral heart score were significantly associated with survival time (p ＜ 0.05). Additionally, age, left atrial-to-aortic root ratio, ejection fraction, and left ventricular end diastolic volume were associated with an increased risk of death (p ＜ 0.1), while body weight, body condition score, systolic blood pressure, arrhythmia, syncope, fractional shortening, and end systolic volume were not associated with an increased risk of death. These results suggest that among the assessed variables dyspnea, pulmonary edema, and vertebral heart score could be useful prognostic factors for providing patient information to owners.

Correction: Enhanced Hepatogenic Transdifferentiation of Human Adipose Tissue Mesenchymal Stem Cells by Gene Engineering with Oct4 and Sox2.

[This corrects the article DOI: 10.1371/journal.pone.0108874.].

Mesenchymal Stem Cells Contribute to Improvement of Renal Function in a Canine Kidney Injury Model.

BACKGROUND/AIM: The kidney excretes waste materials and regulates important metabolic functions, and renal disorders constitute a significant medical problem and can result in fatalities. In the present study, mesenchymal stem cells derived from canine umbilical cord blood (cUCB-MSCs) were isolated and evaluated for their ability to improve renal function in a canine model of acute kidney injury (AKI). MATERIALS AND METHODS: The canine AKI model was developed by i.v. injection of cisplatin and gentamycin into 14 male beagle dogs. cUCB-MSCs were administered into the renal corticomedullary junction following AKI induction. Survival time, clinical signs, blood analysis and histological parameters were analyzed. RESULTS: The group treated with AKI plus cUCB-MSCs had decreased blood urea nitrogen and creatinine levels, and showed an extended life-span and improved histological manifestations. MSCs were detected around the tubules of these kidneys at the histological level. CONCLUSION: Taken together, our findings suggest that cUCB-MSCs could be an alternative therapeutic agent for canine AKI.

Hyperammonemic hepatic encephalopathy management through L-ornithin-L-aspartate administration in dogs.

Seventeen dogs were treated with L-ornithin-L-aspartate (LOLA; experimental group). Three dogs were treated with lactulose recognized therapy (control group). Following LOLA administration, 15 dogs experienced a significant decrease in ammonia level (p ＜ 0.05) and showed clinical signs of improvement. However, there were no clinical signs of improvement in two dogs, even though the ammonia level decreased. Conversely, the clinical signs of the control group also improved and the ammonia level decreased, although these changes were not significant (p ＞ 0.05). These results suggest that LOLA is an effective drug to treat hyperammonemia in veterinary medicine.

Canine adipose tissue-derived mesenchymal stem cells ameliorate severe acute pancreatitis by regulating T cells in rats.

Severe acute pancreatitis (SAP) is associated with systemic complications and high mortality rate in dogs. Mesenchymal stem cells (MSCs) have been investigated for their therapeutic potential in several inflammation models. In the present study, the effects of canine adipose tissue-derived (cAT)-MSCs in a rat model of SAP induced by retrograde injection of 3% sodium taurocholate solution into the pancreatic duct were investigated. cAT-MSCs labeled with dioctadecyl-3,3,3'-tetramethylindo-carbocyanine perchlorate (1 × 107 cells/kg) were systemically administered to rats and pancreatic tissue was collected three days later for histopathological, quantitative real-time polymerase chain reaction, and immunocytochemical analyses. Greater numbers of infused cAT-MSCs were detected in the pancreas of SAP relative to sham-operated rats. cAT-MSC infusion reduced pancreatic edema, inflammatory cell infiltration, and acinar cell necrosis, and decreased pancreatic expression of the pro-inflammatory cytokines tumor necrosis factor-α, interleukin (IL)-1ß, -6, -12, -17, and -23 and interferon-γ, while stimulating expression of the anti-inflammatory cytokines IL-4 and IL-10 in SAP rats. Moreover, cAT-MSCs decreased the number of clusters of differentiation 3-positive T cells and increased that of forkhead box P3-positive T cells in the injured pancreas. These results indicate that cAT-MSCs can be effective as a cell-based therapeutic strategy for treatment of SAP in dogs.

Enhanced hepatogenic transdifferentiation of human adipose tissue mesenchymal stem cells by gene engineering with Oct4 and Sox2.

Adipose tissue mesenchymal stem cells (ATMSCs) represent an attractive tool for the establishment of a successful stem cell-based therapy in the field of liver regeneration medicine. ATMSCs overexpressing Oct4 and Sox2 (Oct4/Sox2-ATMSCs) showed enhanced proliferation and multipotency. Hence, we hypothesized that Oct4 and Sox2 can increase "transdifferentiation" of ATMSCs into cells of the hepatic lineage. In this study, we generated Oct4- and Sox2-overexpressing human ATMSCs by liposomal transfection. We confirmed the expression of mesenchymal stem cell surface markers without morphological alterations in both red-fluorescent protein (RFP) (control)- and Oct4/Sox2-ATMSCs by flow cytometry. After induction of differentiation into hepatocyte-like cells, the morphology of ATMSCs changed and they began to appear as round or polygonal epithelioid cells. Hepatic markers were evaluated by reverse transcription-polymerase chain reaction and confirmed by immunofluorescence. The results showed that albumin was strongly expressed in hepatogenic differentiated Oct4/Sox2-ATMSCs, whereas the expression level of α-fetoprotein was lower than that of RFP-ATMSCs. The functionality of hepatocytes was evaluated by periodic acid-Schiff (PAS) staining and urea assays. The number of PAS-positive cells was significantly higher and urea production was significantly higher in Oct4/Sox2-ATMSCs compared to that in RFP-ATMSCs. Taken together, the hepatocyte-like cells derived from Oct4/Sox2-ATMSCs were mature hepatocytes, possibly functional hepatocytes with enhanced capacity to store glycogen and produce urea. In this study, we demonstrated the enhanced transdifferentiation of Oct4- and Sox2-overexpressing ATMSCs into hepatocyte-like cells that have enhanced hepatocyte-specific functions. Therefore, we expect that Oct4/Sox2-ATMSCs may become a very useful source for hepatocyte regeneration or liver cell transplantation.

Pro-apoptotic and Growth-inhibitory Effect of IFN-ß-Overexpressing Canine Adipose Tissue-derived Mesenchymal Stem Cells Against Melanoma Cells.

BACKGROUND: Canine melanoma is the most common type of tumor in dogs. We investigated the effects of canine interferon-beta (cIFN-ß)-overexpressing adipose tissue-derived mesenchymal stem cells (cATMSCs) on apoptosis and proliferation of canine melanoma cells. MATERIALS AND METHODS: Expression of IFN-ß in cATMSCs was confirmed using reverse transcription-polymerase chain reaction and enzyme linked immunosorbent assays. Flow cytometry was performed for cell-cycle analysis and apoptotic cell quantification of LMeC (melanoma) cells. Protein expression of cyclin D1, procaspase-3, activated caspase-3, and Bcl-2 homologous antagonist killer (Bak) was evaluated by western blot analysis. RESULTS: Decreased proportions of cells in S- and G0/G1 phases were observed in parallel with decreased cyclin D1 expression in LMeC cells treated with cIFN-ß-cATMSC-conditioned media. Protein expression of active forms of caspase 3 and Bak increased in response to treatment with cIFN-ß-cATMSC-conditioned media. CONCLUSION: IFN-ß overexpression by cATMSCs was associated with pro-apoptotic and growth-inhibitory effects on canine melanoma cells. The antitumor effects of these cells have therapeutic potential for the treatment of canine melanoma.

Enhanced proliferation and differentiation of Oct4- and Sox2-overexpressing human adipose tissue mesenchymal stem cells.

Mesenchymal stem cells (MSCs) are attractive candidates for clinical repair or regeneration of damaged tissues. Oct4 and Sox2, which are essential transcription factors for pluripotency and self-renewal, are naturally expressed in MSCs at low levels in early passages, and their levels gradually decrease as the passage number increases. Therefore, to improve MSC proliferation and stemness, we introduced human Oct4 and Sox2 for conferring higher expansion and differentiation capabilities. The Oct4-IRES-Sox2 vector was transfected into human adipose tissue MSCs (ATMSCs) by liposomal transfection and used directly. Oct4 and Sox2 were successfully transfected into ATMSCs, and we confirmed maintenance of MSC surface markers without alterations in both red fluorescent protein (RFP) (control) and Oct4/Sox2-ATMSCs. Enhanced proliferative activity of Oct4/Sox2-ATMSCs was shown by WST-1 assay, and this result was further confirmed by cell counting using trypan blue exclusion for a long period. In addition, FACs cell cycle analysis showed that there was a reduction in the fraction of Oct4/Sox2-ATMSCs in G1 with a concomitant increase in the fraction of cells in S, compared with RFP-ATMSCs. Increased levels of cyclin D1 were also seen in Oct4/Sox2-ATMSCs, indicating acceleration in the transition of cells from G1 to S phase. Furthermore, Oct4/Sox2-overexpressing ATMSCs showed higher differentiation abilities for adipocytes or osteoblasts than controls. The markers of adipogenic or osteogenic differentiation were also upregulated by Oct4/Sox2 overexpression. The improvement in cell proliferation and differentiation using Oct4/Sox2 expression in ATMSCs may be a useful method for expanding the population and increasing the stemness of ATMSCs.