Azetidine-2-Carboxylic Acid-Induced Oligodendrogliopathy: Relevance to the Pathogenesis of Multiple Sclerosis.

The naturally occurring imino acid azetidine-2-carboxylic acid (Aze) is consumed by humans and can be misincorporated in place of proline in myelin basic protein (MBP) in vitro. To determine Aze effects on the mammalian CNS in vivo, adult CD1 mice were given Aze orally or intraperitoneally. Clinical signs reminiscent of MBP-mutant mice occurred with 600 mg/kg Aze exposure.

Anti-Myelin Proteolipid Protein Peptide Monoclonal Antibodies Recognize Cell Surface Proteins on Developing Neurons and Inhibit Their Differentiation.

Using a panel of monoclonal antibodies (mAbs) to myelin proteolipid protein (PLP) peptides, we found that in addition to CNS myelin, mAbs to external face but not cytoplasmic face epitopes immunostained neurons in immature human CNS tissues and in adult hippocampal dentate gyrus and olfactory bulbs, that is neural stem cell niches (NSCN). To explore the pathobiological significance of these observations, we assessed the mAb effects on neurodifferentiation in vitro. The mAbs to PLP 50-69 (IgG1κ and IgG2aκ), and 178-191 and 200-219 (both IgG1κ) immunostained live cell surfaces and inhibited neurite outgrowth of E18 rat hippocampal precursor cells and of PC12 cells, which do not express PLP.

Review of the history and current status of cell-transplant approaches for the management of neuropathic pain.

Treatment of sensory neuropathies, whether inherited or caused by trauma, the progress of diabetes, or other disease states, are among the most difficult problems in modern clinical practice. Cell therapy to release antinociceptive agents near the injured spinal cord would be the logical next step in the development of treatment modalities. But few clinical trials, especially for chronic pain, have tested the transplant of cells or a cell line to treat human disease.

Potential for Cell-Transplant Therapy with Human Neuronal Precursors to Treat Neuropathic Pain in Models of PNS and CNS Injury: Comparison of hNT2.17 and hNT2.19 Cell Lines.

Effective treatment of sensory neuropathies in peripheral neuropathies and spinal cord injury (SCI) is one of the most difficult problems in modern clinical practice. Cell therapy to release antinociceptive agents near the injured spinal cord is a logical next step in the development of treatment modalities. But few clinical trials, especially for chronic pain, have tested the potential of transplant of cells to treat chronic pain.

Subarachnoid Transplant of the Human Neuronal hNT2.19 Serotonergic Cell Line Attenuates Behavioral Hypersensitivity without Affecting Motor Dysfunction after Severe Contusive Spinal Cord Injury.

Transplant of cells which make biologic agents that can modulate the sensory and motor responses after spinal cord injury (SCI) would be useful to treat pain and paralysis. To address this need for clinically useful human cells, a unique neuronal cell line that synthesizes and secretes/releases the neurotransmitter serotonin (5HT) was isolated. Hind paw tactile allodynia and thermal hyperalgesia induced by severe contusive SCI were potently reversed after lumbar subarachnoid transplant of differentiated cells, but had no effect on open field motor scores, stride length, foot rotation, base of support, or gridwalk footfall errors associated with the SCI.

Clinical feasibility for cell therapy using human neuronal cell line to treat neuropathic behavioral hypersensitivity following spinal cord injury in rats.

Management of neuropathic pain remains problematic; however, cell therapy to treat the effects of pain on the sensory system after spinal cord injury (SCI) could be a useful approach. Since many clinical trials ultimately do not succeed, use of cell therapy will require that safety and efficacy issues be addressed early in preclinical rat studies. We used the human neuronal cell line hNT2.

The combination of human neuronal serotonergic cell implants and environmental enrichment after contusive SCI improves motor recovery over each individual strategy.

A human neuronal cell line, hNT2.19, which secretes serotonin (5-HT) after differentiation, was used as a transplant source to improve motor dysfunction following severe contusive spinal cord injury (SCI). Also, environmental enrichment (EE) was added to the interspinal transplant treatment paradigm.

Social and environmental enrichment improves sensory and motor recovery after severe contusive spinal cord injury in the rat.

Neuropathic pain and motor dysfunction are difficult problems following spinal cord injury (SCI). Social and environmental enrichment (SEE), which models much of the clinical rehabilitation environment for post-SCI persons, is the focus of the current investigation which examines the effects of multiple-housing and the addition of climbing spaces, improved bedding and crawl toys on the sensory and motor recovery following a severe contusive SCI. Efficacy was determined with sensory testing, open-field motor behavioral testing, lesion volume analysis and quantification of brain-derived neurotrophic factor (BDNF) in the lumbar spinal cord with and without SEE provided during the recovery period.

Optimizing the transplant dose of a human neuronal cell line graft to treat SCI pain in the rat.

Neuropathic pain is a prevalent and difficult problem in the setting of spinal cord injury (SCI). The use of cellular transplant therapy to treat this pain has been successful with the use of a human neuronal cell line, hNT2.17 [M.

Subarachnoid transplant of a human neuronal cell line attenuates chronic allodynia and hyperalgesia after excitotoxic spinal cord injury in the rat.

Unlabelled: The relief of neuropathic pain after spinal cord injury (SCI) remains daunting, because pharmacologic intervention works incompletely and is accompanied by multiple side effects. Transplantation of human cells that make specific biologic agents that can potentially modulate the sensory responses that are painful would be very useful to treat problems such as pain. To address this need for clinically useful human cells, the human neuronal NT2 cell line was used as a source to isolate a unique human neuronal cell line that synthesizes and secretes/releases the inhibitory neurotransmitters gamma-aminobutyric acid (GABA) and glycine.

Cell and molecular approaches to the attenuation of pain after spinal cord injury.

Recent experimental research to treat spinal cord injury (SCI) pain has greatly increased our understanding of how such chronic pain might be modulated in the human population. Neuropathic pain is caused by the structural and biochemical changes associated with the peripheral and central nervous system damage associated with nervous system trauma, often leading to an imbalance in endogenous excitatory and inhibitory spinal systems that modulate sensory processing. But current pharmacological therapies are often ineffective over time for the greater number of patients.

Monoclonal antibodies to distinct regions of human myelin proteolipid protein simultaneously recognize central nervous system myelin and neurons of many vertebrate species.

Myelin proteolipid protein (PLP), the major protein of mammalian CNS myelin, is a member of the proteolipid gene family (pgf). It is an evolutionarily conserved polytopic integral membrane protein and a potential autoantigen in multiple sclerosis (MS). To analyze antibody recognition of PLP epitopes in situ, monoclonal antibodies (mAbs) specific for different regions of human PLP (50-69, 100-123, 139-151, 178-191, 200-219, 264-276) were generated and used to immunostain CNS tissues of representative vertebrates.

Interferon-beta counteracts inflammatory mediator-induced effects on brain endothelial cell tight junction molecules-implications for multiple sclerosis.

To elucidate mechanisms of endothelial cell (EC) dysfunction in CNS inflammatory responses and beneficial effects of interferon-beta (IFN-gamma) in multiple sclerosis (MS), we analyzed effects of individual and combinations of soluble inflammatory mediators on the intracellular localization of the EC tight junction-associated molecules zonula occludens-1 and -2 (ZO-1 and ZO-2) in human brain ECs. The cytoplasm in the majority of cells in control EC cultures was clear; ZO-1 and ZO-2 were localized peripherally near sites of cell contact and associated with submembranous cytoplasmic filaments. H2O2 induced reversible time- and concentration-dependent translocation of ZO-1 and ZO-2 to a random distribution within EC cytoplasm and retraction of EC borders.

Immortalized chromaffin cells disimmortalized with Cre/lox site-directed recombination for use in cell therapy for pain after partial nerve injury.

To prepare immortalized adrenal chromaffin cells for eventual clinical use, the immortalizing oncogene must be removed. We have utilized a Cre-mediated excision of a loxP-flanked Tag sequence to test whether immortalized chromaffin cells could be disimmortalized by this method. Cultures of embryonic rat adrenal cells were immortalized with the tsA-TN retroviral vector encoding the loxP-flanked temperature-sensitive allele of SV40 large T antigen (tsA-TN) and a positive/negative neo/HSV-TK sequence for selection with either G418 or gancyclovir, respectively.

Intralesion transplantation of serotonergic precursors enhances locomotor recovery but has no effect on development of chronic central pain following hemisection injury in rats.

The effects of intralesion grafts of serotonergic precursors on locomotor recovery and development of chronic pain were assessed after chronic spinal cord hemisection injury (SCI) in rats. Serotonin- and brain-derived neurotrophic factor-secreting (RN46A-B14) and RN46A-vector-only cells were transplanted into the site of T13 lateral hemisection 10 days following injury in immunosuppressed animals, and locomotor and pain related behaviors were assessed weekly for 28 days. There were significant improvements in the degree of spontaneous locomotor recovery, but no significant difference was found in the magnitude of development of mechanical allodynia or thermal hyperalgesia in any transplant group.