Identification of differentially expressed genes in gauze-exposed omentum of dogs using differential display RT-PCR

Molecular mechanisms governing peritonitis caused by the presence of aseptic gauze have remained unclear. To identify the genes involved, sterile gauze-exposed omentum was collected at 0, 6, 12, 24, and 48 h intervals, and analyzed by differential display RT(reverse transcription)-PCR. Among over 1,200 bands, 230 bands were found differentially expressed. These bands represented the fragment sizes of approximately 200 to 1,500 bp. The eight fragments were expressed differentially in the treatment group but not in the control. The sequences of two bands were similar to those of genes associated with the inflammatory process and a band was related to repair and regeneration process. Another one was related with spermatogonia and the rest four were unknown. Additionally, amplicons corresponding to the full-length sequences of two inflammatory gene fragments were synthesized by rapid amplification of cDNA end PCR. One showed 99% similarity to the major histocompatibility complex class II dog leukocyte antigen-DR beta chain and the other was canis familiaris proteasome beta type 3. Results of the present study suggested that sterile gauze induced the differential expression of genes in the omentum involved in inflammation and healing process.

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.

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.