Functional recovery and neural differentiation after transplantation of allogenic adipose-derived stem cells in a canine model of acute spinal cord injury

In this study, we evaluated if the implantation of allogenic adipose-derived stem cells (ASCs) improved neurological function in a canine spinal cord injury model. Eleven adult dogs were assigned to three groups according to treatment after spinal cord injury by epidural balloon compression: C group (no ASCs treatment as control), V group (vehicle treatment with PBS), and ASC group (ASCs treatment). ASCs or vehicle were injected directly into the injured site 1 week after spinal cord injury. Pelvic limb function after transplantation was evaluated by Olby score. Magnetic resonance imaging, somatosensory evoked potential (SEP), histopathologic and immunohistichemical examinations were also performed. Olby scores in the ASC group increased from 2 weeks after transplantation and were significantly higher than C and V groups until 8 weeks (p<0.05). However, there were no significant differences between the C and V groups. Nerve conduction velocity based on SEP was significantly improved in the ASC group compared to C and V groups (p < 0.05). Positive areas for Luxol fast blue staining were located at the injured site in the ASC group. Also, GFAP, Tuj-1 and NF160 were observed immunohistochemically in cells derived from implanted ASCs. These results suggested that improvement in neurological function by the transplantation of ASCs in dogs with spinal cord injury may be partially due to the neural differentiation of implanted stem cells.

Cerebellar vermian hypoplasia in a Cocker Spaniel

An eight-week-old female Cocker Spaniel was presented with ataxia, dysmetria and intention tremor. At 16 weeks, the clinical signs did not progress. Investigation including imaging studies of the skull and cerebrospinal fluid analysis were performed. The computed tomography revealed a cyst-like dilation at the level of the fourth ventricle associated with vermal defect in the cerebellum. After euthanasia, a cerebellar hypoplasia with vermal defect was identified on necropsy. A polymerase chain reaction amplification of cerebellar tissue revealed the absence of an in utero parvoviral infection. Therefore, the cerebellar hypoplasia in this puppy was consistent with diagnosis of primary cerebellar malformation comparable to Dandy-Walker syndrome in humans.

Implantation of canine umbilical cord blood-derived mesenchymal stem cells mixed with beta-tricalcium phosphate enhances osteogenesis in bone defect model dogs

This study was performed to evaluate the osteogenic effect of allogenic canine umbilical cord blood-derived mesenchymal stem cells (UCB-MSCs) mixed with beta-tricalcium phosphate (beta-TCP) in orthotopic implantation. Seven hundred milligrams of beta-TCP mixed with 1 x 10(6) UCB-MSCs diluted with 0.5 ml of saline (group CM) and mixed with the same volume of saline as control (group C) were implanted into a 1.5 cm diaphyseal defect and wrapped with PLGC membrane in the radius of Beagle dogs. Radiographs of the antebrachium were made after surgery. The implants were harvested 12 weeks after implantation and specimens were stained with H&E, toluidine blue and Villanueva-Goldner stains for histological examination and histomorphometric analysis of new bone formation. Additionally, UCB-MSCs were applied to a dog with non-union fracture. Radiographically, continuity between implant and host bone was evident at only one of six interfaces in group C by 12 weeks, but in three of six interfaces in group CM. Radiolucency was found only near the bone end in group C at 12 weeks after implantation, but in the entire graft in group CM. Histologically, bone formation was observed around beta-TCP in longitudinal sections of implant in both groups. Histomorphometric analysis revealed significantly increased new bone formation in group CM at 12 weeks after implantation (p < 0.05). When applied to the non-union fracture, fracture healing was identified by 6 weeks after injection of UCB-MSCs. The present study indicates that a mixture of UCB-MSCs and beta-TCP is a promising osteogenic material for repairing bone defects.

Establishment of a canine spinal cord injury model induced by epidural balloon compression

A model that provides reproducible, submaximal yet sufficient spinal cord injury is needed to allow experiments leading to development of therapeutic techniques and prediction of clinical outcome to be conducted. This study describes an experimental model for spinal cord injury that uses three different volumes of balloon inflation and durations of compression to create a controlled gradation outcome in adult dogs. Twenty-seven mongrel dogs were used for this study. A 3-french embolectomy catheter was inserted into the epidural space through a left hemilaminectomy hole at the L4 vertebral arch. Balloons were then inflated with 50, 100, or 150 microliter of a contrast agent at the L1 level for 6, 12, or 24 h and spinal canal occlusion (SCO) measured using computed tomography. Olby score was used to evaluate the extent of spinal cord injury and a histopathologic examination was conducted 1 week after surgery. The SCO of the 50, 100, and 150 microliter inflations was 22-46%, 51-70%, and 75-89%, respectively (p 50% for 24 h, and > 75% for 12 h induces paraplegia up to a week after spinal cord injury.

Transplantation of canine umbilical cord blood-derived mesenchymal stem cells in experimentally induced spinal cord injured dogs

This study was to determine the effects of allogenicumbilical cord blood (UCB)-derived mesenchymal stemcells (MSCs) and recombinant methionyl humangranulocyte colony-stimulating factor (rmhGCSF) on acanine spinal cord injury model after balloon compressionat the first lumbar vertebra. Twenty-five adult mongreldogs were assigned to five groups according to treatmentafter a spinal cord injury: no treatment (CN); salinetreatment (CP); rmhGCSF treatment (G); UCB-MSCstreatment (UCB-MSC); co-treatment (UCBG). The UCB-MSCs isolated from cord blood of canine fetuses wereprepared as 10(6) cells/150microl saline. The UCB-MSCs weredirectly injected into the injured site of the spinal cord andrmhGCSF was administered subcutaneously 1 week afterthe induction of spinal cord injury. The Olby score,magnetic resonance imaging, somatosensory evokedpotentials and histopathological examinations were used toevaluate the functional recovery after transplantation. TheOlby scores of all groups were zero at the 0-week evaluation.At 2 week after the transplantation, the Olby scores in thegroups with the UCB-MSC and UCBG were significantlyhigher than in the CN and CP groups. However, there wereno significant differences between the UCB-MSC andUCBG groups, and between the CN and CP groups. Thesecomparisons remained stable at 4 and 8 week aftertransplantation. There was significant improvement in thenerve conduction velocity based on the somatosensory evokedpotentials. In addition, a distinct structural consistency ofthe nerve cell bodies was noted in the lesion of the spinalcord of the UCB-MSC and UCBG groups. These resultssuggest that transplantation of the UCB-MSCs resulted inrecovery of nerve function in dogs with a spinal cord injuryand may be considered as a therapeutic modality for spinalcord injury.

Erratum: Establishment of a canine spinal cord injury model induced by epidural balloon compression

The 150 microl and 50 micol was reversed in the labeled line of the insert box in above article, on page 92, Fig. 4. The correct figure is printed below. We apologize for any confusion resulting from this error.

Guided bone regeneration with beta-tricalcium phosphate and poly Llactide-co-glycolide-co-epsilon-caprolactone membrane in partial defects of canine humerus

This study was performed to evaluate the effect of betatricalcium phosphate and poly L-lactide-co-glycolide-coepsilon- caprolactone (TCP/PLGC) membrane in the repair of partial bone defects in canine proximal humerus. Three adult mixed-breed dogs were used during the experimental period. The length of the defect was quarter of the full length of humerus, and width of the defect was quarter of middle diameter of the lateral aspect of humerus. The humeri of each dog were divided into treatment (TCP/ PLGC) and control groups. The defect was covered with TCP/PLGC membrane in treatment group. To evaluate regeneration of the bone, computerized tomography (CT) and histopathologic examination were performed. The radiopaque lines were appeared at the original defect sites in TCP/PLGC group but below the original site in control at 4th week. Radiopacity and thickness of the defect sites, and radiopaque lines were more increased at 8th week than those of 4th week. Histopathologic findings revealed fibrous connective tissue migration into the defect and the migration inhibited the structure of new cortex to be placed in the original level in control whereas new cortex growth was found in the level of original line in TCP/ PLGC group. However, the new cortical bone in the TCP/ PLGC group was thinner and less organized than the adjacent intact cortex, and the amount of new cancellous bones were also scanty. The result suggested that TCP/ PLGC membrane is a good guided bone regeneration material to restore the original morphology of humerus in partial defect.

A Case of oculocutaneous albinism in a Maltese

A 4-month-old female maltese dog was admitted to Veterinary Medical Teaching Hospital of Seoul National University for evaluation of abnormal color of bilateral irises. This patient had the photophobia in the light and exhibited the complete absence of pigment resulting in white hair, pink muzzle, eyelids and foot-pads. Central zone of the irises were yellow in color influenced by tapetal reflex, and peripheral zone were pale blue. The iridal capillaries were transparented on the irises. Ophthalmoscopic examination revealed a yellow tapetal fundus but no pigment in the nontapetal fundus.

Mutation and overexpression of p53 as a prognostic factor in canine mammary tumors

We concentrated ourselves to evaluate the prognostic significance of the p53 gene mutations, its protein expression and MIB-1 index as a proliferative marker in canine mammary tumors. In the present study, a total of 20 cases were examined, among which there were 5 malignant mixed tumors, 4 mammary gland adenocarcinomas, 1 papillary adenocarcinoma, 8 benign mixed tumors and 2 mammary gland adenomas. Positive immunostaining for p53 with PAb240 antibody was found in 2 benign (20%) and 3 malignant (30%) tumors. However, PAb421 antibody did not give positive result at all. In Western blot analysis, the p53 expression in benign and malignant tumors was detected in 4 and 3 cases, respectively. p53 mutations were found in 6 cases out of the cases with detected p53 protein expression. The MIB-1 index in benign and malignant tumors were 17.6+/-20.8% and 29.0+/-27.2%, respectively and there was no significant difference between tumor types. There was a significant correlation between p53 mutations and p53 overexpression (correlation coefficient = 0.5, p < 0.05). In Kaplan-Meier survival analysis, the p53 index was associated with significantly shortened survival time (p < 0.01). In multivariate analysis, p53 overexpression was only an independent factor for indicator of worse prognosis in canine mammary tumors (p = 0.01). These results demonstrated that p53 gene mutations and protein overexpression using the PAb240 anti-p53 antibody were useful predictors of increased malignant potential and poor prognosis in canine mammary tumors.