Joseph D. Ciacci

Amelioration of motor/sensory dysfunction and spasticity in a rat model of acute lumbar spinal cord injury by human neural stem cell transplantation

IntroductionIntraspinal grafting of human neural stem cells represents a promising approach to promote recovery of function after spinal trauma. Such a treatment may serve to: I) provide trophic support to improve survival of host neurons; II) improve the structural integrity of the spinal parenchyma by reducing syringomyelia and scarring in trauma-injured regions; and III) provide neuronal populations to potentially form relays with host axons, segmental interneurons, and/or α-motoneurons. Here we characterized the effect of intraspinal grafting of clinical grade human fetal spinal cord-derived neural stem cells (HSSC) on the recovery of neurological function in a rat model of acute lumbar (L3) compression injury.MethodsThree-month-old female Sprague–Dawley rats received L3 spinal compression injury. Three days post-injury, animals were randomized and received intraspinal injections of either HSSC, media-only, or no injections. All animals were immunosuppressed with tacrolimus, mycophenolate mofetil, and methylprednisolone acetate from the day of cell grafting and survived for eight weeks. Motor and sensory dysfunction were periodically assessed using open field locomotion scoring, thermal/tactile pain/escape thresholds and myogenic motor evoked potentials. The presence of spasticity was measured by gastrocnemius muscle resistance and electromyography response during computer-controlled ankle rotation. At the end-point, gait (CatWalk), ladder climbing, and single frame analyses were also assessed. Syrinx size, spinal cord dimensions, and extent of scarring were measured by magnetic resonance imaging. Differentiation and integration of grafted cells in the host tissue were validated with immunofluorescence staining using human-specific antibodies.ResultsIntraspinal grafting of HSSC led to a progressive and significant improvement in lower extremity paw placement, amelioration of spasticity, and normalization in thermal and tactile pain/escape thresholds at eight weeks post-grafting. No significant differences were detected in other CatWalk parameters, motor evoked potentials, open field locomotor (Basso, Beattie, and Bresnahan locomotion score (BBB)) score or ladder climbing test. Magnetic resonance imaging volume reconstruction and immunofluorescence analysis of grafted cell survival showed near complete injury-cavity-filling by grafted cells and development of putative GABA-ergic synapses between grafted and host neurons.ConclusionsPeri-acute intraspinal grafting of HSSC can represent an effective therapy which ameliorates motor and sensory deficits after traumatic spinal cord injury.

Single-Isocenter Frameless Intensity-Modulated Stereotactic Radiosurgery for Simultaneous Treatment of Multiple Brain Metastases: Clinical Experience

PURPOSE To describe our clinical experience using a unique single-isocenter technique for frameless intensity-modulated stereotactic radiosurgery (IM-SRS) to treat multiple brain metastases. METHODS AND MATERIALS Twenty-six patients with a median of 5 metastases (range, 2-13) underwent optically guided frameless IM-SRS using a single, centrally located isocenter. Median prescription dose was 18 Gy (range, 14-25). Follow-up magnetic resonance imaging (MRI) and clinical examination occurred every 2-4 months. RESULTS Median follow-up for all patients was 3.3 months (range, 0.2-21.3), with 20 of 26 patients (77%) followed up until their death. For the remaining 6 patients alive at the time of analysis, median follow-up was 14.6 months (range, 9.3-18.0). Total treatment time ranged from 9.0 to 38.9 minutes (median, 21.0). Actuarial 6- and 12-month overall survivals were 50% (95% confidence interval [C.I.], 31-70%) and 38% (95% C.I., 19-56%), respectively. Actuarial 6- and 12-month local control (LC) rates were 97% (95% C.I., 93-100%) and 83% (95% C.I., 71-96%), respectively. Tumors <or=1.5 cm had a better 6-month LC than those >1.5 cm (98% vs. 90%, p = 0.008). New intracranial metastatic disease occurring outside of the treatment volume was observed in 7 patients. Grade >or=3 toxicity occurred in 2 patients (8%). CONCLUSION Frameless IM-SRS using a single-isocenter approach for treating multiple intracranial metastases can produce clinical outcomes that compare favorably with those of conventional SRS in a much shorter treatment time (<40 minutes). Given its faster treatment time, this technique is appealing to both patients and personnel in busy clinics.

Chronic Spinal Compression Model in Minipigs: A Systematic Behavioral, Qualitative, and Quantitative Neuropathological Study

The goal of the present study was to develop a porcine spinal cord injury (SCI) model, and to describe the neurological outcome and characterize the corresponding quantitative and qualitative histological changes at 4-9 months after injury. Adult Gottingen-Minnesota minipigs were anesthetized and placed in a spine immobilization frame. The exposed T12 spinal segment was compressed in a dorso-ventral direction using a 5-mm-diameter circular bar with a progressively increasing peak force (1.5, 2.0, or 2.5 kg) at a velocity of 3 cm/sec. During recovery, motor and sensory function were periodically monitored. After survival, the animals were perfusion fixed and the extent of local SCI was analyzed by (1) post-mortem MRI analysis of dissected spinal cords, (2) qualitative and quantitative analysis of axonal survival at the epicenter of injury, and (3) defining the presence of local inflammatory changes, astrocytosis, and schwannosis. Following 2.5-kg spinal cord compression the animals demonstrated a near complete loss of motor and sensory function with no recovery over the next 4-9 months. Those that underwent spinal cord compression with 2 kg force developed an incomplete injury with progressive partial neurological recovery characterized by a restricted ability to stand and walk. Animals injured with a spinal compression force of 1.5 kg showed near normal ambulation 10 days after injury. In fully paralyzed animals (2.5 kg), MRI analysis demonstrated a loss of spinal white matter integrity and extensive septal cavitations. A significant correlation between the magnitude of loss of small and medium-sized myelinated axons in the ventral funiculus and neurological deficits was identified. These data, demonstrating stable neurological deficits in severely injured animals, similarities of spinal pathology to humans, and relatively good post-injury tolerance of this strain of minipigs to spinal trauma, suggest that this model can successfully be used to study therapeutic interventions targeting both acute and chronic stages of SCI.

Pig models of neurodegenerative disorders: Utilization in cell replacement-based preclinical safety and efficacy studies.

An important component for successful translation of cell replacement‐based therapies into clinical practice is the utilization of large animal models to conduct efficacy and/or safety cell dosing studies. Over the past few decades, several large animal models (dog, cat, nonhuman primate) were developed and employed in cell replacement studies; however, none of these models appears to provide a readily available platform to conduct effective and large‐scale preclinical studies. In recent years, numerous pig models of neurodegenerative disorders were developed using both a transgenic approach as well as invasive surgical techniques. The pig model (naïve noninjured animals) was recently used successfully to define the safety and optimal dosing of human spinal stem cells after grafting into the central nervous system (CNS) in immunosuppressed animals. The data from these studies were used in the design of a human clinical protocol used in amyotrophic lateral sclerosis (ALS) patients in a Phase I clinical trial. In addition, a highly inbred (complete major histocompatibility complex [MHC] match) strain of miniature pigs is available which permits the design of comparable MHC combinations between the donor cells and the graft recipient as used in human patients. Jointly, these studies show that the pig model can represent an effective large animal model to be used in preclinical cell replacement modeling. This review summarizes the available pig models of neurodegenerative disorders and the use of some of these models in cell replacement studies. The challenges and potential future directions in more effective use of the pig neurodegenerative models are also discussed. J. Comp. Neurol. 522:2784–2801, 2014.

Survival and differentiation of human embryonic stem cell-derived neural precursors grafted spinally in spinal ischemia-injured rats or in naive immunosuppressed minipigs: a qualitative and quantitative study.

In previous studies, we have demonstrated that spinal grafting of human or rat fetal spinal neural precursors leads to amelioration of spasticity and improvement in ambulatory function in rats with spinal ischemic injury. In the current study, we characterize the survival and maturation of three different human embryonic stem (ES) cell line-derived neural precursors (hNPCs) once grafted into ischemia-injured lumbar spinal cord in rats or in naive immunosuppressed minipigs. Proliferating HUES-2, HUES-7, or HUES-9 colonies were induced to form embryoid bodies. During the nestin-positive stage, the rosettes were removed and CD184+/CD271-/CD44-/CD24+ population of ES-hNPCs FAC-sorted and expanded. Male Sprague–Dawley rats with spinal ischemic injury or naive immunosuppressed Gottingen–Minnesota minipigs received 10 bilateral injections of ES-NPCs into the L2–L5 gray matter. After cell grafting, animals survived for 2 weeks to 4.5 months, and the presence of grafted cells was confirmed after staining spinal cord sections with a combination of human-specific (hNUMA, HO14, hNSE, hSYN) or nonspecific (DCX, MAP2, CHAT, GFAP, APC) antibodies. In the majority of grafted animals, hNUMA-positive grafted cells were identified. At 2–4 weeks after grafting, double-labeled hNUMA/ DCX-immunoreactive neurons were seen with extensive DCX+ processes. At survival intervals of 4–8 weeks, hNSE+ neurons and expression of hSYN was identified. Some hSYN-positive terminals formed putative synapses with the host neurons. Quantitative analysis of hNUMA+ cells at 2 months after grafting showed comparable cell survival for all three cell lines. In the presence of low-level immunosuppression, no grafted cell survival was seen at 4.5 months after grafting. Spinal grafting of proliferating pluripotent HUES-7 cells led to consistent teratoma formation at 2–6 weeks after cell transplantation. These data show that ES-derived, FAC-sorted NPCs can represent an effective source of human NPCs to be used in CNS cell replacement therapies.

Gene- and Cell-Based Approaches for Neurodegenerative Disease

Neurodegenerative diseases comprise an important group ofchronic diseases that increase in incidence with rising age. In particular, the two most common neurodegenerative diseases are Alzheimers disease and Parkinsons disease, both of which will be discussed below. A third, Huntingtons disease, occurs infrequently, but has been studied intensely. Each of these diseases shares characteristics which are also generalizeable to other neurodegenerative diseases: accumulation ofproteinaceous substances that leads inexorably to selective neuronal death and decline in neural function. Treatments for these diseases have historically focused on symptomatic relief, but recent advances in molecular research have identified more specific targets. Additionally, stem cell therapy, immunotherapy and trophic-factor delivery provide avenues for neuronal protection that may alter the natural progression of these devastating illnesses. Upcoming clinical trials will evaluate treatment strategies and provide hope that translational research will decrease the onset of debilitating disability associated with neurodegenerative disease.

Pituitary Tumor Apoplexy in Adolescents

OBJECTIVE The aim of this study was to determine whether there are differences in pituitary apoplexy and subclinical apoplexy secondary to adenoma hemorrhage in the adolescent population with regard to symptomatology, neuroimaging features, pathology, and outcomes compared with adults. METHODS A retrospective series of 9 consecutive patients with a diagnosis of pituitary hemorrhage who were surgically treated at Radys Childrens Hospital San Diego, between 2008 and 2013 were evaluated for clinical, endocrine, neuroradiographic, and pathologic features in association with clinical outcomes. RESULTS Nine patients (6 girls, age 14-21 years) presented to our institution with headache (9/9), nausea (3/9), dizziness (4/9), and visual disturbances (6/9) in the setting of a sellar hemorrhagic tumor on magnetic resonance imaging (MRI). Three patients presented with apoplexy and 6 with subclinical apoplexy. Duration of symptoms ranged from 3 days to 1 year. MRI revealed hemorrhage (9/9), rim enhancement (6/9), sphenoid sinus mucosal thickening (2/9), mass effect on the optic chiasm (8/9), and sellar remodeling (9/9). The percentage of hemorrhage preoperatively observed on MRI ranged from 50% to greater than 95%. On presentation, hyperprolactinemia was recorded in 7 patients, 6 of whom had galactorrhea and/or amenorrhea. Open transsphenoidal decompression was performed in 8/9 patients; 7 of 9 were diagnosed with prolactinoma. Biopsy specimens revealed 10%-90% hemorrhage and no infarction in any of the cases. All patients treated showed improvement of symptoms after surgery (average follow-up, 28.2 months). Postoperative complications included transient diabetes insipidus (n = 5), persistent cerebrospinal fluid rhinorrhea (n = 3), and meningitis (n = 1). Five patients had long-term endocrine sequelae of hyperprolactinemia requiring ongoing medical treatment. CONCLUSIONS Pituitary hemorrhage resulting in apoplexy or subclinical apoplexy in adolescents may represent a distinct entity with a more indolent symptomatology and more favorable neurologic and endocrine outcome compared with adults that is worthy of further validation in a multi-institutional cohort.

Stem Cells in the Treatment of Stroke

Stroke is an often devastating insult resulting in neurological deficit lasting greater than 24 hours. In the United States, stroke is the third leading cause of death. In those who do not succumb, any outcome from total recovery over a period of weeks to months to persistent profound neurological deficits is possible. Present treatment centers on the decision to administer tissue plasminogen activator, subsequent medical stabilization and early intervention with rehabilitation and risk factor management. The advent of stem cell therapy presents an exciting new frontier for research in stroke treatment, with the potential to cause a paradigm shift from symptomatic control and secondary prevention to reconstitution of neural networks and prevention of neuronal cell death after neurologic injury.

172 A Phase I, Open-Label, Single-Site, Safety Study of Human Spinal Cord-Derived Neural Stem Cell Transplantation for the Treatment of Chronic Spinal Cord Injury.

INTRODUCTION Spinal cord injury (SCI) resulting in paraplegia or quadriplegia is a significant burden in the world. It is estimated that there are approximately 250 000 people living with SCI in the United States alone. Our study offered the direct implantation of human-derived stem cells into the spinal cord of subjects who have chronic SCI. The primary objective of the study is to determine the safety and toxicity of human spinal stem cell transplantation for the treatment of paralysis. The secondary objectives of the study are to evaluate (1) graft survival in the transplant site, (2) effectiveness of transient immunosuppression as determined by absence of donor-specific HLA antibodies, and (3) potential therapeutic role of implantation on motor and sensory function in SCI. METHODS This is a phase I, open-label, single-site, study of human spinal cord-derived neural stem cell (HSSC) transplantation for the treatment of chronic SCI. Four subjects with chronic SCI with ASIA A SCI who met eligibility criteria were enrolled. All subjects received spinal cord injections of HSSC. The treatment consisted of removal of spinal instrumentation followed by direct injections into spinal parenchyma. Six HSSC injections were administered in each subject. Each injection consisted of 2 × 10 cells in 10 µL. RESULTS Four subjects have been implanted to date. All subjects tolerated the procedure well and there have been no major adverse events to date. Prospective data has been collected including ISNCSCI scores, ASIA level, functional and pain surveys, SCIM scores, Sensory and Motor Evoked potentials, EMG, and MRI including a novel sequence of MR spinal diffusion tensor imaging (DTI). These metrics are continuing to be collected and evaluated. CONCLUSION We can conclude that (1) HSSC transplanted into the injury site of a spinal cord in chronic spinal cord injury patients can be done safely. (2) The HSSC graft has been shown to have no major adverse events to date.

Potent spinal parenchymal AAV9-mediated gene delivery by subpial injection in adult rats and pigs

Effective in vivo use of adeno-associated virus (AAV)-based vectors to achieve gene-specific silencing or upregulation in the central nervous system has been limited by the inability to provide more than limited deep parenchymal expression in adult animals using delivery routes with the most clinical relevance (intravenous or intrathecal). Here, we demonstrate that the spinal pia membrane represents the primary barrier limiting effective AAV9 penetration into the spinal parenchyma after intrathecal AAV9 delivery. We develop a novel subpial AAV9 delivery technique and AAV9-dextran formulation. We use these in adult rats and pigs to show (i) potent spinal parenchymal transgene expression in white and gray matter including neurons, glial and endothelial cells after single bolus subpial AAV9 delivery; (ii) delivery to almost all apparent descending motor axons throughout the length of the spinal cord after cervical or thoracic subpial AAV9 injection; (iii) potent retrograde transgene expression in brain motor centers (motor cortex and brain stem); and (iv) the relative safety of this approach by defining normal neurological function for up to 6 months after AAV9 delivery. Thus, subpial delivery of AAV9 enables gene-based therapies with a wide range of potential experimental and clinical utilizations in adult animals and human patients.