Objective: Inhibition of dendritic cell (DC) maturation and activation, and the consequent interference with the normal functioning of cell-mediated immunity, is frequently observed in subjects during the chronic phase of traumatic spinal cord injury (SCI). The underlying mechanisms that mediate SCI-induced immunological changes are poorly understood. This has hampered the development of immune-based therapies which could: 1) prevent or slow down further tissue damage observed in chronic SCI and 2) promote tissue regeneration. In the current work we sought to uncover novel molecular pathways in SCI-induced immune changes by performing whole-genome microarray and molecular pathway analyses.
Study design: Male subjects were recruited from an ongoing study of health and SCI patients. Subjects with motor complete chronic SCI (> 2 years post-injury) were identified based on low hip bone density. Subjects without SCI and normal hip bone density comprised the control group. Microarray analysis using Affymetrix HG-U133A GeneChip® array was performed with RNA extracted from circulating monocytes. Partek Genomic Suite (PGS) software was used to limit the 54,000 gene list to only those genes up-regulated or down-regulated by 2 fold or more with a p value < 0.05 in SCI compared to control. Pathway analyses were performed with Ingenuity Systems IPA software to identify biological pathways of interest involving differentially expressed genes. Genes of interested were then confirmed by quantitative PCR (qPCR).
Results: Six SCI subjects and five controls participated in the final analyses. A molecular pathway related to immune cell trafficking was identified as being significantly upregulated in the SCI subjects. Two genes in that network, TMEM176A and TMEM176B, were notable for the magnitude of overexpression (fold changes of +5.2 and +11.9 respectively). qPCR studies confirmed overexpression (42.4 y 84.1 fold).
Discussion: DCs have been shown to mediate recovery and/or protective autoimmunity in a variety of central nervous system (CNS) injuries and have the capacity to induce neuroprotection and neurogenesis in stroke patients. High TMEM176A and TMEM176B levels have been shown to prevent DC maturation and to inhibit DC activity in healthy populations. Here, we have demonstrated increased overexpression of both genes in SCI compared to control subjects. Thus, we conclude that the role of these two genes in inhibiting protective immune responses should be investigated, particularly as possible targets of therapies designed to promote immune system-mediated neuroprotection and recovery in SCI.

Introduction:
Spinal cord injury (SCI) causes prolonged morbidity with loss of neurologic function and initiates an excessively prolonged and destructive inflammation. Inflammatory cells rapidly invade the outer spinal cord (glia limitans) after SCI. In areas of necrosis and hemorrhage, myelin-rich phagocytizing macrophages invade causing expansion of granulomatous tissue termed arachnoiditis with marked destruction of the spinal cord. Holes or cavities form at sites of SCI and prevent regrowth of neuronal extension across the cavity of injury (COI). Serp-1 is a 55 kD glycosylated myxomavirus-derived serine protease inhibitor (serpin) with proven immune modulating activity, reducing damaging inflammation and improving outcomes after arterial injury and solid organ transplant. Serp-1 targets and inhibits both thrombotic and thrombolytic proteases controlling excess hemorrhage and also inflammatory mononuclear cell activation. When infused in saline, recombinant Serp-1 reduced early inflammatory cell invasion after balloon crush SCI in rats. Hydrogel injection at sites of spinal trauma provide a scaffold for regrowth of neurons across the cavity of injury. Intralesion hydrogel injection at sites of spine trauma has the potential to provide a scaffold for regrowth of neurons across the cavity of injury.

Methods:
We investigated local infusion of a chitosan-collagen hydrogel with gradual serpin release at sites of local forceps injury (L1) in Long Evans rats. The Serp-1 hydrogel was prepared by first binding Serp-1 to chitosan followed by lyophilization and reconstitution into a collagen I solution. Serp-1 hydrogel was tested at 10 and 100 microgram/50 μL gel doses with comparison to hydrogel alone (N=17 rats). We measured the Hind End (HE) motor and toe pinch withdrawal function, as well as urinary bladder and body weight each day. Spines were collected after euthanization at day 28.

Results:
At 3-21 days after injury the higher dose (100 μg/50μL/rat) of Serp-1 significantly improved neurologic function (HE motor P=0.0018; and toe pinch withdrawal; P=0.019) with improved weight gain. Examination of the urinary bladder demonstrated a trend toward improved function with higher dose Serp-1, while lower dose did not improve function. Histological analysis demonstrated a significant reduction in arachnoiditis in higher dose Serp-1 rats (P=0.0018). Serp-1 at higher doses preserved the architecture of small blood vessels and capillaries in the spinal cord 3-4 mm distant from the area of inflammation. However, small blood vessels in control chitosan and low dose Serp-1 had thickened wall, hypertrophied endothelium and perivascular astroglial reactions indicating widespread vascular damage and related edema. Histopathological changes correlated closely with the observed early, improved neural function.

Conclusions: Intralesional injection of Serp-1 hydrogel after SCI reduces inflammation and edema and improves neurologic function. Serpin-mediated targeting of thrombolytic protease and inflammatory proteases in a local hydrogel infusion has potential as a new therapeutic approach to reduce inflammation, preserve vessel integrity and improve neurological function after SCI.

[Background and aims]
This study aimed to explore the dynamic diffusion tensor imaging (DTI) of changes in spinal cord and brain structure after spinal cord injury (SCI). Quantitative diffusion tensor imaging can provide information about the microstructure of nerve tissue and can quantify the pathological damage of spinal cord and brain.

[Methods]
DTI was performed on dogs with injured spinal cords using a Siemens 3.0T MRI scanner at pre-contusion and at different weeks post-injury. The tissue sections were stained for immunohistochemical analysis. Also, DTI imaging were acquired in patients with SCI as well as clinical data.

[Results]
In the canine models of spinal cord contusion, the series of DTI values (FA, ADC, MD, RD) changes apparently. Immunohistological analysis of GFAP and NF revealed the pathologic changes of reactive astrocytes and axons, as well as the cavity and glial scars occurring during chronic SCI. And compared to controls, SCI patients had decreased FA and increased MD and RD in extensive brain areas. Differences were also observed between the cervical and thoracic SCI patients. And correlations between the time since injury, retained function and DTI values were revealed.

[Conclusions]
DTI is a sensitive and noninvasive imaging tool useful to assess edema, hemorrhage, cavity formation, structural damage and reconstruction of axon, and myelin in SCI. The DTI parameters after contusion vary and were affected by distance and time, and the caudal degradation appeared to be more severe than the rostral one. It seems that the apparent diffusion-coefficient value for white matter could predict the recovery of neurological function accurately after SCI. This study also suggests that multiple cerebral WM tracts are damaged in SCI patients, and WM disruption in cervical SCI is worse than thoracic injury level, especially in the posterior thalamic radiation (PTR) region.

Introduction: Cervical spinal cord lesion typically causes damage to the upper motoneuron (UMN) below the level of lesion. At the level of lesion, also the lower motoneuron (LMN) can be affected. The extent of the damage and thus the involvement of the LMN can vary and influences the function, structure and treatment options of the hand and forearm muscles as well as decision-making in nerve transfers.

Objective: The aim of the study was to measure the innervation pattern of two finger flexors and two finger extensors in tetraplegic patients and to compare the distribution of innervated, partially innervated and denervated muscles.

Methods: The M. flexor digitorum profundus (FDP) and the M. flexor pollicis longus (FPL) were tested according to standardized electrical stimulation (ES) protocol in patients with tetraplegia C2-TH1 AIS A-D. A muscle was classified as innervated if full range of motion was achieved under electrical stimulation in accordance to the British Medical Research Council Scale (MRC) for manual muscle testing. A muscle was judged partially innervated if a value of less than 3 according to MRC was achieved and as denervated if no contraction and movement occurred during ES testing. The innervation pattern data of three radial nerve innervated muscles (M. extensor digitorum communis (EDC) and M. extensor pollicis longus (EPL), M. abductor pollicis longus (APL)) from a previously published study of the same population was used for comparison. A cartography was developed on the palmar and on the dorsal aspect of the forearm. ES tests of these muscles were performed as part of the evaluation for reconstructive tetrahand surgery in in- and out patients.

Results: The data of 55 patients with a mean age of 44.4 ± 18.1 years with 3.9 ± 8.6 years after spinal cord injury were analysed. 44 forearms on the palmar and 63 forearms on the dorsal aspect were tested with ES. In the 44 ES tested FDP the distribution of innervated to partially innervated and denervated muscles was 66.0% to 22.7% to 11.4%, in the FPL 40.9% to 27.3% to 31.8%. In EDC, 66.7% were innervated, 1.6% partially innervated and 31.7% denervated. In the thumb muscles EPL/APL 69.9% showed innervation, 4.0% partial innervation and 30.2% denervation. The proportion of partially innervated muscles was higher in the flexors than in the extensors.

Conclusion: Electrical stimulation to determine the innervation pattern of hand and forearm muscles is a reliable assessment tool to detect an UMN or LMN lesion and could be recommended for use in rehabilitation. Knowledge of the innervation pattern and the number of partially innervated muscles, especially in the flexors, provides crucial information about timing and expected outcome of nerve transfer surgery for restoration of grip function.

Title:
DuraGenTM as an encapsulating material for neural stem cell delivery

Objectives:
Achieving neural regeneration after spinal cord injury (SCI) represents a significant challenge. Neural stem cell (NSC) therapy offers replacement of damaged cells and delivery of pro-regenerative factors, but >95% of cells die when transplanted to sites of neural injury. Biomaterial scaffolds provide cellular protective encapsulation to improve cell survival. However, current available scaffolds are overwhelmingly not approved for human use, presenting a major barrier to clinical translation. Surgical biomaterials offer the unique benefit of being FDA-approved for human implantation. Specifically, a neurosurgical grade material, DuraGenTM, used predominantly for human duraplasty has many attractive features of an ideal biomaterial scaffold. Here, we have investigated the use of DuraGenTM as a 3D cell encapsulation device for potential use in combinatorial, regenerative therapies.

Methods:
Primary NSCs were seeded into optimised sheets of DuraGenTM. NSC growth and fate within DuraGenTM were assessed using 3D microscopic fluorescence imaging techniques.

Results:
DuraGenTM supports the survival (ca 95% viability, 12 days) and 3D growth of NSCs. NSC phenotype, proliferative capacity and differentiation into astrocytes, neurons and oligodendrocytes were unaffected by DuraGenTM.

Conclusions:
A ‘combinatorial therapy’, consisting of NSCs protected within a DuraGenTM matrix, offers a potential clinically translatable approach for neural cell therapy.

Introduction: Time is an important consideration in the newest surgical technique to improve upper extremity function: nerve transfers. These techniques are poised to transform the management of the upper limbs for people with cervical SCI. However nerve transfers can be time sensitive due to axonal and muscle degeneration. There is a need for more information on natural recovery and function after SCI to help patient and clinician decision-making regarding this novel surgical treatment. The objective of this study was to establish the probability of spontaneous recovery of function and degree of gains in independence after cervical SCI, and to identify possible candidates who would benefit from early nerve transfer surgery.

Methods: Using the European Multi-center Study about Spinal Cord Injury (EMSCI) data set, analysis was undertaken of eligible individuals with traumatic SCI, motor level C5-C8. The EMSCI database includes rigorously and prospectively collected neurological and functional independence measurements. Recovery of motor function between 6 and 12 months after injury was ascertained. Data on feeding, bladder management and transfers (wheelchair to bed) were compared at 6 months and 12 months after injury for each neurologic level. Subgroup analyses of symmetric and asymmetric SCI, and between complete and incomplete SCI were performed. The impact of age, gender, and degree of asymmetry on functional independence was ascertained.

Results: From 6 to 12 months post-SCI, few patients recovered additional strong (MRC 4-5) function below the neurologic level. Specifically, analysis of 418 limbs showed that 4% of individuals with strong proximal cervical level function (C5 +/- C6 +/- C7 intact) and no C8 function at 6 months gained strong C8 level function (finger flexion) by 12 months. With respect to recovery of C7 (elbow extension) function, of those with intact proximal level function at 6 months (N=260 limbs), 6% gained antigravity (MRC 3/5) and 2% gained strong (MRC 4-5/5) C7 function at 12 months.

At 6 months post injury, data were available for 176 individuals with symmetric patterns of injury. At C5-level, assistance was required for feeding, bladder function and transfers. At C6-level, 35% of individuals could eat independently using assistive devices/partial assistance for cutting, 4% were independent with bladder management, and 2% could transfer independently. At C7-level, 58% could eat using assist devices/assistance for cutting, 28% had independent bladder function, and only 19% transferred independently. At C8-level, 84% could eat independently or with assistive devices/partial assistance for cutting, 52% had independent bladder management, and 36% transferred independently. There was no statistically significant change from 6 to 12 months though a trend towards gain in function was seen.

Conclusion: Overall, few patients spontaneously gained additional function from 6 to 12 months post-SCI. Individuals with C6 (active wrist extension and tenodesis-driven hand use) and C8 (some hand function) level injuries gained greater independence with feeding and bladder management tasks. Those with C8 gained greater independence with transfers than those with C7 (active elbow extension). This work supports early (within 6 months of injury) evaluation for possible peripheral nerve transfer surgery to augment upper limb function.

INTRODUCTION
Individuals who suffer from paralysis after spinal cord injury (SCI) undergo dramatic decreases in muscle mass below the level of injury and an estimated ~66% prevalence of obesity. However, when adjusting body mass index (BMI) for the loss of muscle after SCI, a combined overweight and obesity rate is as high as 70% to 75%. Obesity is a major public health concern and is associated with a plethora of cardiometabolic health complications (heart disease, stroke and type II diabetes mellitus); thus, it is understandable that people with SCI are more than twice as likely to develop these disorders.

It has been well documented that physical activity can promote a healthy body composition and decrease the risk cardiometabolic disease. This has been especially true for high intensity interval training exercise. However, SCI typically limits voluntary exercise to the arms. This is problematic because high prevalence of shoulder pain in persons with chronic SCI (60-90%), often limits the possibility of regular arm exercise. On the other hand, functional electrical stimulation (FES) cycling has proven to be a safe and effective way to exercise paralyzed leg muscles in clinical and home settings, saving the often overworked arms. Yet, there has been no invesitghation into the effects of high intensity interval training (HIIT) FES cycling. The purpose of this study was to invesitgate the body composition effects of combined HIIT-FES cycling and nutritional counseling on individuals with SCI

METHODS
Design: A injury level matched controlled trail. Setting: University exercise performance laboratory. Subjects: Ten individuals with chronic SCI (C5-T9) ASIA impairment classification (A & B) were divided into the treatment group (n=5) for 30 minutes of HIIT-FES cycling 3 times per week for 8 weeks and nutrionional counseling over the phone for 30 minutes once per week for 8 weeks and the control group (n=5) for nutritional counseling only.

RESULTS
A significant difference existed between the control and treatment group on body fat percentage (BF%) (t = -2.628, p = .030) and legs lean mass (t = 4.060, p = .004). A significant difference did not exist in weight, BMI, total fat mass, or total lean mass. For body fat percentage, participants in the treatment group decreased (M = 1.14%) while those in the control group increased (M = 2.8%). In other words, participants’ BF% who used HIIT-FES cycling and nutritional counseling reduced more during the timeframe of the study compared to those who only used nutritional counseling. Additionally, participants in the treatment group gained more lean mass in their legs (M = 1.08kg) compared to the control group (M = -1.05kg). Four out of the five participants in the treatment group lost weight while one participant had no change.
CONCLUSION
HITT-FES cycling combined with nutritional counseling can provide healthful body composition changes including decreased body fat percentage in just 8 weeks.