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Artículo científico -- Universidad de Costa Rica. Instituto de Investigaciones en Salud, 2001. Este documento es privado debido a limitaciones de derechos de autor. Autosomal recessive Charcot-Marie-Tooth disease (CMT) represents a heterogeneous group of disorders affecting the peripheral nervous system. The axonal form of the disease is designated as "CMT type 2" (CMT2), and one locus (1q21.2-q21.3) has been reported for the autosomal recessive form. Here we report the results of a genomewide search in an inbred Costa Rican family (CR-1) affected with autosomal recessive CMT2. By analyzing three branches of the family we detected linkage to the 19q13.3 region, and subsequent homozygosity mapping defined shared haplotypes between markers D195902 and D19S907 in a 5.5-cM range. A maximum two-point LOD score of 9.08 was obtained for marker 019S867, at a recombination fraction of .00, which strongly supports linkage to this locus. The epithelial membrane protein 3 gene, encoding a PMP22 homologous protein and located on 19q13.3, was ruled out as being responsible for this form of CMT. The age at onset of chronic symmetric sensory-motor polyneuropathy was 28-42 years (mean 33.8 years); the electrophysiological data clearly reflect an axonal degenerative process. The phenotype and locus are different from those of demyelinating CMT4F, recently mapped to 19q13.1-13.3; hence, the disease affecting the Costa Rican family constitutes an axonal, autosomal recessive CMT subtype (ARCMT2B). Universidad de Costa Rica. Instituto de Investigaciones en Salud UCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias de la Salud::Instituto de Investigaciones en Salud (INISA)

Segmental muscle enlargement occurs in a variety of neurogenic conditions. We present a patient with calf hypertrophy, likely produced by continuous neuromuscular irritability and compensatory type 1 and type 2 muscle fiber hypertrophy. The underlying lesion of the SI nerve root was caused by scarring, which could be demonstrated by Cadolinum enhanced, fat saturated magnetic resonance imaging. Thus, the application of this technique is recommended in otherwise etiologically unclear cases of neurogenic muscular lesions in order to detect chronic nerve root pathology. [Neurol Res 2000; 22: 469-472]

Chronic venous insufficiency (CVI) of the lower legs may cause tissue damage, but involvement of peripheral nerves is uncertain. We examined 30 patients with CVI and 20 healthy controls using motor and sensory nerve conduction studies, vibration testing and thermotesting, quantitative sudomotor axon-reflex test, and laser Doppler flowmetry. Subjects with possible confounding factors for peripheral neuropathies were excluded. Prolongation of distal motor latency of the peroneal nerve (median, 5.4 versus 4.5 ms; P = 0.02), increased limits for warm (9.60 degrees C versus 5.20 degrees C; P = 0.016) and cold detection (3.45 degrees C versus 1.55 degrees C; P = 0.016) and reduced vibration sense (2.8925 versus 1.1075; P < 0.008) were found. The results demonstrate a disturbance of A-alpha fibers, A-beta fibers, A-delta fibers, and thermoafferent-C fibers, possibly induced by ischemia due to venous microangiopathy and increased endoneurial pressure. Analogous to neuropathic ulcers in diabetes, the CVI-associated neuropathy may also be a cofactor in the development of venous ulcers.

Die haufigste Ursache der Polyneuropathien (PNP) ist mit ca. 35% der Diabetes, ca. 22% der Falle sind ungeklarter Atiologie, ca. 11% alkoholinduziert, zusammen etwa 2 Drittel aller Falle. Unter den weiteren Ursachen der PNP finden sind Vaskulitiden in ca. 4%. Pathogenetisch resultiert als Folge von entzundlichen Infiltraten der Gefaswande, Stenosierungen der Vasa nervorum oder Einblutungen schlieslich die ischamische Lasion von Nervenfasern, die zu einer axonalen Degeneration fuhrt. Die folgende Ubersicht geht zunachst auf die Klassifikation der Vaskulitiden ein, wobei festgestellt werden muss, dass die hier aus der Sicht des Neurologen verwendete Klassifikation sich von der heutzutage ublicherweise in der Inneren Medizin bevorzugten Einteilung der Vaskulitiden entsprechend der Chapel-Hill-Consensus-Conference (nach dem Gefastyp) unterscheidet. Sodann werden wesentliche Gesichtspunkte zur Epidemiologie, Pathophysiologie, Pathomorphologie und Diagnostik beschrieben und systematisch die Nosologie der verschiedenen Formen der Vaskulitiden unter besonderer Berucksichtigung neurologischer Storungen referiert. In tabellarischer Form werden bewahrte, neue und experimentelle Therapieoptionen dargestellt. Fur die tagliche Praxis sollte festgehalten werden, dass neurologische Symptome im Sinn einer PNP immer auch an eine Vaskulitisinduzierte Ursache denken lassen sollten.

Vasculitic neuropathy shows cluster of differentiation (CD)4+ and CD8+ perivascular infiltrates. CD8+ cells kill the target by different ways. Some mechanisms require the release of granzymes and T-cell restricted intracellular antigen (TIA-1) which induce cell death by apoptosis. A nonsecretory ligand-mediated mechanism has been proposed for apoptosis and requires the interaction of Fas and Fas-ligand. We studied apoptosis by immunohistochemistry and terminal deoxynucleotidyl transferase-mediated nick end labeling (TUNEL) in nerve biopsy specimens in 19 cases of vasculitic neuropathy and 8 controls. In vasculitic neuropathy, perivascular mononuclear cells expressed TIA-1, granzyme A, and granzyme B. Regarding the ligand-mediated mechanism, we observed Fas+ and Fas-ligand+ mononuclear cells in an epineurial-perivascular distribution. Cells undergoing apoptosis, as demonstrated by TUNEL, represented mononuclear cells. In vasculitic neuropathy, apoptosis by both a secretory and a nonsecretory mechanism is suspected. However, apoptosis seems to be restricted to inflammatory mononuclear cells, suggesting that it may play a critical role in recovery from vasculitic neuropathy.

Multiple system atrophy represents an enigmatic, clinico-pathologically defined neurodegenerative disease. According to findings of the last three decades, the historically derived, previously used terms olivopontocerebellar atrophy, striatonigral degeneration, and Shy-Drager-syndrome should be avoided in clinical use because of both the clinical and morphological overlap between these syndromes. Complex neurodegenerative syndromes other than multiple system atrophy according to recently developed criteria, should rather be referred to as multiple system degenerations.

Hepatitis C virus (HCV) infection is often associated with abnormal immunological responses. We describe four patients with vasculitic neurological signs and symptoms following HCV infection. A 56-year-old woman with HCV infection developed peripheral neuropathy characterized by asymmetric distal painful hypesthesia, dysesthesia and moderate motor weakness of the lower limbs. Serological examinations revealed cryoglobulinemia and low levels of complement C4. A biopsy of the sural nerve revealed vasculitic neuropathy. HCV infection associated immunomediated vasculitis was diagnosed. While steroid therapy was ineffective, treatment with interferon-alpha improved the neuropathy considerably without, however, eliminating HCV infection. A 62-year-old man with HCV infection developed peripheral sensory neuropathy. Complement C3 was slightly diminished. Nerve biopsy revealed vasculitic neuropathy. A 71-year-old woman developed chronic symmetric sensomotor polyneuropathy. HCV hepatitis followed blood transfusions. Cryoglobulins tested positive, consistent with type II cryoglobulinemia. Complements C3 and C4 were diminished. Inflammatory infiltrates in the sural nerve biopsy specimen led to the diagnosis of chronic vasculitic disorder. A 55-year-old woman with HCV infection developed vasculitis of the skin, connective tissue, visceral organs, and kidney, leading to hemodialysis. Neurologically she developed severe apathy and drowsiness, myoclonic jerks, exaggerated deep tendon reflexes, and positive pyramidal signs. Magnetic resonance imaging of the brain showed diffuse increased signal abnormalities involving supra- and infratentorial white matter suggesting cerebral vasculitis. Cryoglobulins were positive, complements C3 and C4 slightly diminished (54 mg/dl, 4.3 mg/dl). Supportive therapy resulted in neurological improvement. Treatment with interferon-alpha was discontinued because of agranulocytosis. In patients with peripheral neuropathy or signs of leucencephalopathy, a hepatitis C associated vasculitis should be considered in the differential diagnosis.

Bartonella henselae, the causative agent of cat scratch disease and bacillary angiomatosis, is associated with an expanding spectrum of diseases. Here, we report on a 40-year-old patient suffering from chronic recurrent painful ulcers of the toes, distal axonal sensomotor polyneuropathy and Raynaud's phenomenon. Biopsy of the sural nerve demonstrated an axonal neuropathy with a neurogenic muscular atrophy. Treatment with high dose corticosteroids had no beneficial effect. A biopsy taken from a recurring ulcer 7 years after the beginning of the disease revealed superficial ulcerated hyperkeratosis with subepithelial proliferation of small vessels compatible with a diagnosis of verruca peruana, however, without detection of microorganism. Serologic analysis revealed an elevated IFT titer of 1:1,024 against B. henselae. Treatment with erythromycin induced healing of the ulcer, remission of the vasculitis and the polyneuropathy, and a decline of the IFT titer. This case illustrates that B. henselae infection should be considered in patients with vasculitis and polyneuropathic syndromes.

A multicenter test was conducted to investigate the effectiveness of the selective serotonin agonist sumatriptan in patients with the computerized headache diagnosis of migraine. A computer program was used for diagnostic evaluation of patients attending a general practice because of headache. The results of the analysis were taken as a direct decision on therapy. If the patients satisfied the criteria for migraine, they were given subcutaneous sumatriptan for treating three migraine attacks. The patients were able to use the study medication under outpatient conditions. The therapeutic efficacy of the medicine was recorded in a headache diary. A total of 91 patients were included in the study at 22 practices in Germany. An average of four patients per practice were recruited. In the first migraine attack treated, headache improvement was experienced by 77.7% of the patients treated. In the second and third attacks an improvement was experienced by 93.5% and 89.8%, respectively. The results show that by optimizing diagnostic reliability with the aid of the computer program a high response rate can be achieved under practice conditions using the selective serotonin agonist sumatriptan. Since the computer program described permits a specific diagnosis, it improves the prospects of effective headache therapy in the individual patient. Thus treatment based on this approach can reduce inputs of time and money in migraine therapy.

The insulin like growth factors (IGFs) are mitogenic peptides that can stimulate cell division and differentiation. In experimental studies it has been shown that there is local-production of IGFs and their mRNA in regenerating muscle. The effect of IGF-I and -II is mediated by a cell surface, membrane bound receptor (IGF-I-R). In addition, IGF-II has its own distinct type 2 receptor. But the role of IGF-II binding to the type 2 receptor is unclear, and it is now widely believed that the growth-promoting activities of IGF-II are also mediated via the IGF-I-R. So far, there is some knowledge about the regulation and effects of IGFs in muscle regeneration in vitro and in animal models in vivo. However, cell lines and in vitro experiments with myogenic precursors differ in some respects from human regenerating muscle in vivo. Thus, we performed our immunohistochemical study to investigate the potential role of IGF-II and IGF-I-R in regenerating human skeletal muscle in situ. To investigate the state of regeneration, neural cell adhesion molecule (N-CAM) and cytoskeletal protein vimentin serial sections were also performed. Light-microscopic evaluation showed that muscle fiber regeneration in inflammatory and dystrophic myopathy corresponds closely to IGF-II and IGF-I-R immunoreactivity in muscle fibers. The coexpression of IGF-II and IGF-I-R in regenerating muscle fibers corroborates the assumption that in human skeletal muscle there is a trophic pathway concerning the synthesis and autocrine action of IGF-II via the IGF-I-R. In conclusion, in human skeletal muscle, in vivo, muscle fiber derived IGF-II probably is biologically active on the cell type of origin and may play an autocrine role in muscle regeneration via the IGF-I-R.

Immunoproteasome is a protease abundant in immune cells and also present, albeit at lower concentrations, in cells outside the immune system. Recent evidence supports a novel role for the immunoproteasome in the cellular stress response potentially through regulation of NFκB signaling, which is the primary response to multiple stressors. The current study tests whether the Classical or Alternative Pathways are regulated by immunoproteasome following chronic TNFα exposure in cultured retinal pigment epithelial cells isolated from wild-type mice and mice deficient in one (LMP2, L2) or two (LMP7 and MECL-1, L7M1) immunoproteasome subunits. Assays were performed to assess the expression of NFκB responsive genes, the content and activity of NFκB transcription factors (p65, p50, p52, cRel, RelB), and expression and content of regulatory proteins (IκBα, A20, RPS3). Major findings include distinct differences in expression of NFκB responsive genes in both KO cells. The mechanism responsible for the altered gene expression could not be established for L7M1 since no major differences in NFκB transcription factor content or activation were observed. However, L2 cells exhibited substantially higher content and diminished activation of NFκB transcription factors associated with the Alternative Pathway and delayed termination of the Classical Pathway. These results provide strong experimental evidence supporting a role for immunoproteasome in modulating NFκB signaling.

Recent studies have revealed roles for immunoproteasome in regulating cell processes essential for maintaining homeostasis and in responding to stress and injury. The current study investigates how the absence of immunoproteasome affects the corneal epithelium under normal and stressed conditions by comparing corneas from wildtype (WT) mice and those deficient in two immunoproteasome catalytic subunits (lmp7(-/-)/mecl-1(-/-), L7M1). Immunoproteasome expression was confirmed in WT epithelial cells and in cells of the immune system that were present in the cornea. More apoptotic cells were found in both corneal explant cultures and uninjured corneas of L7M1 compared to WT mice. Following mechanical debridement, L7M1 corneas displayed delayed wound healing, including delayed re-epithelialization and re-establishment of the epithelial barrier, as well as altered inflammatory cytokine production compared to WT mice. These results suggest that immunoproteasome plays an important role in corneal homeostasis and wound healing.

Bei Reizung von Afferenzen des N. trigeminus wird die Willkuraktivitat der Kaumuskulatur typischerweise in 2 aufeinanderfolgenden Phasen (ES1 und ES2) gehemmt. Die erste Hemmphase wird fruhe exterozeptive Suppressionsphase (ES1), die zweite Hemmphase spate exterozeptive Suppressionsphase (ES2) genannt. Die zwischen den beiden Suppressionsperioden gelegene Phase wird als Fazilitationsperiode (FP) bezeichnet. In der Regel ist dieses Suppressionsverhalten bei exterozeptiver Reizung bei Gesunden regelmasig auslosbar. Zwar kann der Reflex auch mit nicht schmerzhaften Reizen ausgelost werden, das Antwortverhalten ist jedoch bei Einsatz von schmerzhaften Reizen maximal. Aufgrund dieses Zusammenhangs zwischen Reizintensitat, Schmerzwahrnehmung und Reflexantwort wird der Reflex als antinozizeptive Reaktion angesehen. Chronische Schmerzerkrankungen wie der chronische Kopfschmerz vom Spannungstyp und die Migrane ohne Aura gehen mit Veranderungen im normalen Ableitbild der ES einher. Ebenso last sich die Auspragung der ES durch unterschiedliche, in der Schmerztherapie angewandte Substanzen wie z. B. Serotoninagonisten-oder antagonisten, Acetylsalicylsaure oder Naloxon beeinflussen. In dieser Ubersicht werden die verschiedenen Einflusgrosen auf die ES-Reflexantwort systematisch aufgezeigt. Darauf aufbauend wird die diagnostische Bedeutung dieser Veranderungen fur pathophysiologische Vorgange in der Schmerzverarbeitung und bei Schmerzerkrankungen dargelegt.

The rationale for using essential oils to alleviate headache is based on several assumptions. Especially for peppermint oil certain analgesic mechanisms were recently described. Local application of peppermint oil generates a long-lasting cooling effect on the skin, caused by a steric alteration of the calcium channels of the cold-receptors. Further it was shown that peppermint oil inhibits non-competively 5-hydroxytryptamin (Serotonine) and substance P induced smooth muscle contraction in animal-models. It is also known that peppermint oil induces a significant increase of the skin blood flow of the forehead after local application, measured by laser doppler. Assuming that a clinical relevant analgesic action exists, this ought to be observable in experimental algesimetric human tests. Therefore the effects of peppermint oil and eucalyptus oil preparations on neurophysiological, psychological and experimental algesimetric parameters were investigated in 32 healthy subjects in a double-blind, placebo-controlled, randomized cross-over design. Four different test preparations were used: preparation 1 (LI1701) consisted of 10 g peppermint oil and 5 g eucalyptus oil plus ethanol 90% to 100 g; preparation 2 (LI1702) of 10 g peppermint oil and traces of eucalyptus oil plus ethanol 90% to 100g; preparation 3 (LI1703) of traces of peppermint oil and 5 g eucalyptus oil plus ethanol 90% to 100 g; and preparation 4 (placebo) of traces of peppermint oil and traces of eucalyptus oil plus ethanol 90% to 100 g. The test preparations were applied to large areas of the forehead and temples using a small sponge. The treatment effect of the preparations was evaluated by comparing baseline and treatment measurements. The combination of peppermint oil, eucalyptus oil and ethanol can increase cognitive performance while having a muscle-relaxing and mentally relaxing effect, but has little influence on pain sensitivity. A significant analgesic effect with a reduction in sensitivity to headache is however produced by the combination of peppermint oil and ethanol. The essential plant oil preparations can thus be shown by laboratory tests to exert significant effects on mechanisms associated with the pathophysiology of clinical headache syndromes. Further, to investigate the efficacy of essential oil preparations compared to usual analgesics (paracetamol or acetylsalicylicacid) a double blind, placebo controlled, randomized study should be performed.

We report on a patient with an interstitial myositis in type II polyendocrine autoimmune disease (Schmidt's syndrome) showing an immunohistochemical demonstrated perifascicular expression of Leu 19 indicating perifascicular denervation, which could not be detected with classical histological methods. In neurogenic muscular atrophy, idiopathic polymyositis and normal muscle we could not find such an exclusive perifascicular expression of the Leu 19 antigen. We conclude that perifascicular denervation is a characteristic feature in IM and thus might have diagnostic value. Furthermore the interstitial myositis is characterized by a complement-mediated angiopathy (vascular deposition of the membranolytic attack complex C5b-9). This pattern is comparable to well-known changes in dermatomyositis. Interstitial myositis and dermatomyositis are evidently pathogenetically similar according to myopathological criteria, but show phenotypic differences. Additional in interstitial myositis and idiopathic polymyositis inflammatory infiltrates surrounding Leu 19 expressing myocytes are regarded as the cause of disseminated intrafascicular muscle fibre denervation.

The growth-associated protein B-50, also termed GAP-43, is a membrane-bound phosphoprotein that is expressed in neurons. It is particularly abundant during periods of axonal outgrowth in development and regeneration of the central and peripheral nervous system. In this paper we study the expression of B-50 in inflammatory and dystrophic myopathies. To investigate the state of regeneration, N-CAM and vimentin serial sections were performed, because N-CAM and cytoskeletal protein vimentin are excellent markers for regenerating muscle. Light-microscopic evaluation showed that muscle fiber regeneration in myopathies corresponds closely to B-50 immunoreactivity in satellite cells, myoblasts, myotubes and small regenerating myocytes in cytoplasmatic distribution. In normal muscle and in biopsies of neurogenic muscular atrophy, however, no light-microscopically demonstrable B-50 staining was found. B-50 in muscles apparently plays a role in the growth morphology of regenerating myocytes, and the phosphoprotein B-50 can no longer be regarded as a neuron-specific molecule.

While pathogenic CD4 T cells are well known mediators of autoimmune uveoretinitis, CD8 T cells can also be uveitogenic. Since preliminary studies indicated that C57BL/6 mice were minimally susceptible to autoimmune uveoretinitis induction by CD8 T cells, the basis of the retinal disease resistance was sought. Mice that express β-galactosidase (βgal) on a retina-specific promoter (arrβgal mice) were backcrossed to mice expressing green fluorescent protein (GFP) and diphtheria toxin (DTx) receptor (DTR) under control of the Foxp3 promoter (Foxp3-DTR/GFP mice), and to T cell receptor transgenic mice that produce βgal-specific CD8 T cells (BG1 mice). These mice were used to explore the role of regulatory T cells in the resistance to retinal autoimmune disease. Experiments with T cells from double transgenic BG1 × Foxp3-DTR/GFP mice transferred into Foxp3-DTR/GFP × arrβgal mice confirmed that the retina was well protected from attempts to induce disease by adoptive transfer of activated BG1 T cells. The successful induction of retinal disease following unilateral intraocular administration of DTx to deplete regulatory T cells showed that the protective activity was dependent on local, toxin-sensitive regulatory T cells; the opposite, untreated eye remained disease-free. Although there were very few Foxp3(+) regulatory T cells in the parenchyma of quiescent retina, and they did not accumulate in retina, their depletion by local toxin administration led to disease susceptibility. We propose that these regulatory T cells modulate the pathogenic activity of βgal-specific CD8 T cells in the retinas of arrβgal mice on a local basis, allowing immuno regulation to be responsive to local conditions.

A fresh inoculum of human adenovirus type 12 (Ad12) was obtained from the American Type Culture Collection and passaged once on human embryonic kidney cells, and Ad12 DNA was prepared from the first-passage yield to avoid higher passages which might have generated host-virus DNA recombinants. The 18 PstI fragments of Ad12 DNA were cloned into the pBluescript KS vector, and the entire nucleotide sequence of both strands from all 18 fragments was determined by using successive oligodeoxyribonucleotide primers. Ad12 DNA extends over 34,125 nucleotide pairs, and its molecular weight is calculated to be about 22 x 10(6). The nucleotide sequence of Ad12 DNA was subjected to computer analyses that determined possible open reading of frames on the two strands, the leader sequences, the position of the virus-associated RNA coding region, possible TATA, and polyadenylation signals. The distribution of the Ad12 open reading frames was similar to that in the previously sequenced Ad2 DNA, but there were also distinct differences. Ad12 DNA has an inverted terminal redundancy of 161 nucleotides, compared with 102 nucleotides in Ad2 DNA. There were stretches of sequence identity between Ad2 and Ad12 DNAs at both termini; the overall sequence similarity between the two viral genomes ranged between 59% (polypeptide IX) and 77% (in the E2 region), with high homology also in the sequences for the adenovirus DNA polymerase.

OBJECTIVE Annexin-1 is a calcium-binding protein with anti-inflammatory properties, which has previously been described in MS plaque tissue. We investigated the feasibility and specificity of annexin-1-immuncytochemistry of CSF cells to test its potential as a surrogate marker for MS. MATERIALS AND METHODS CSF-specimens of 49 MS cases with different courses and 94 control cases were immunocytochemically studied with a monoclonal antibody to annexin-1. RESULTS The highest level of cytoplasmic immunoreaction was seen in the most acute inflammatory disorders, such as bacterial meningitis and neuroborreliosis. CIS-, RR-MS-, and viral meningoencephalitis cases came next. The lowest annexin-1 expression was observed in neurosyphilis and SP-MS. In PP-MS and non-inflammatory control cases, annexin-1 expression was entirely lacking. CONCLUSION Immunocytochemical staining of CSF cells with an antibody to annexin-1 is feasible. This may be helpful in further study of its role in the pathophysiology of inflammatory CNS diseases. The expression pattern seems to rather reflect the acuteness of the inflammatory process than specifying a certain underlying pathology. Although differences were observed between diverse disease groups, because of considerable overlap, a certain diagnosis of an individual case cannot be achieved. Thus, at present, we cannot recommend annexin-1 as a reliable surrogate marker of MS.

The presence and activity of dendritic cells (DC) in retina is controversial, as these cells are difficult to identify in retina due to limited markers and sparse numbers. Transgenic mice that express green fluorescent protein (GFP) on the CD11c promoter to label DC allowed the visualization and quantification of retinal DC. Two retina injury models, the optic nerve crush (ONC) and light injury, were used to study their injury response. Many GFP(+) DC were tightly associated with retinal ganglion cell nerve fibers following ONC, while very few microglia (GFP(-)CD11b(+) cells) were found in close contact. The GFP(+) cells were greatly elevated in the outer plexiform layer following photic injury. All of the GFP(+) DC were CD11b(+), suggesting a myeloid origin. In addition, the GFP(+) DC upregulated expression of MHC class II after injury, while the GFP(-)CD11b(+) microglia did not. This study shows that DC were found in the retina and that they rapidly responded to neural injuries. We propose that they are a previously overlooked population, distinct from microglia, and may be important in the injury response.

Virus-specific CD8+ T cells (TCD8+) are initially triggered by peptide-MHC Class I complexes on the surface of professional antigen presenting cells (pAPC). Peptide-MHC complexes are produced by two spatially distinct pathways during virus infection. Endogenous antigens synthesized within virus-infected pAPC are presented via the direct-presentation pathway. Many viruses have developed strategies to subvert direct presentation. When direct presentation is blocked, the cross-presentation pathway, in which antigen is transferred from virus-infected cells to uninfected pAPC, is thought to compensate and allow the generation of effector TCD8+. Direct presentation of vaccinia virus (VACV) antigens driven by late promoters does not occur, as an abortive infection of pAPC prevents production of these late antigens. This lack of direct presentation results in a greatly diminished or ablated TCD8+ response to late antigens. We demonstrate that late poxvirus antigens do not enter the cross-presentation pathway, even when identical antigens driven by early promoters access this pathway efficiently. The mechanism mediating this novel means of viral modulation of antigen presentation involves the sequestration of late antigens within virus factories. Early antigens and cellular antigens are cross-presented from virus-infected cells, as are late antigens that are targeted to compartments outside of the virus factories. This virus-mediated blockade specifically targets the cross-presentation pathway, since late antigen that is not cross-presented efficiently enters the MHC Class II presentation pathway. These data are the first to describe an evasion mechanism employed by pathogens to prevent entry into the cross-presentation pathway. In the absence of direct presentation, this evasion mechanism leads to a complete ablation of the TCD8+ response and a potential replicative advantage for the virus. Such mechanisms of viral modulation of antigen presentation must also be taken into account during the rational design of antiviral vaccines., Author Summary Understanding the pathways by which protective immunity is mediated against viral pathogens is essential to allow the design of effective vaccines. No effective vaccine has been designed to activate killer cells of the immune system expressing CD8, although CD8+ T cells are the most effective cells at modulating anti-viral immunity. We have studied the process that activates the CD8+ T cell to better understand how the cells are triggered so future vaccines might readily activate these cells. CD8+ T cells are activated following recognition of small peptides derived from a virus that binds to a cell surface MHC molecule. Many viruses have evolved to prevent the presentation of these peptide-MHC complexes to CD8+ T cells. However, the immune system avoids these viral “evasion” mechanisms by allowing virus-derived peptides to be generated from viral proteins that are taken up by uninfected cells, a process termed “cross presentation”. We have shown that a poxvirus can specifically prevent the presentation of its proteins by uninfected cells, the first demonstration of evasion of cross presentation. This knowledge is vital in the use of certain viral vectors during vaccine design and adds to the numerous ways in which viruses can evade the immune system.

Ziel: Neuromuskulare Erkrankungen (NME) stellen eine erhebliche Belastung fur die Betroffenen und ihren Angehorigen, aber auch fur das Sozialsystem dar. Im deutschsprachigen Raum stehen bislang keine gesundheitsokonomischen Evaluationen dieser Erkrankungsgruppe zur Verfugung. Ziel dieser multizentrischen Studie war die Erhebung der direkten und indirekten Krankheitskosten verschiedener NME in Deutschland. Methoden und Patienten: Eingeschossen wurden 76 Patienten mit den Diagnosen amyotrophe Lateralsklerose (ALS, n=26), Myasthenia gravis (MSG, n=35) oder fazioskapulohumerale Muskeldystrophie (FSHD, n=18). Die Rekrutierung erfolgte in den neurologischen Ambulanzen der Philipps-Universitat Marburg, Universitat Munster, Universitat Bonn, Universitat Nurnberg, Universitat Magdeburg, und neurologischen Kliniken in Darmstadt und Wiesbaden. Die Kostendaten wurden als „bottom-up“ Ansatz mittels einer Patientenbefragung erhoben. Die Kostenbetrachtung wurde aus gesellschaftlicher Perspektive vorgenommen. Es wurden die Preise des Untersuchungsjahres (2003) berucksichtigt. Die direkten Kosten bestanden aus Ausgaben der Kostentrager (Gesetzliche Krankenversicherung und Pflegeversicherung) und Eigenleistungen der Patienten. Die indirekten Kosten entstanden durch Produktivitatsverlust der Patienten und ihrer Angehorigen wurden mit dem Humankapitalansatz ermittelt. Da Kostendaten schief verteilt sind, wurde eine Bootstrap-Analyse durchgefuhrt. Ergebnisse: Die gesamte Jahreskosten der NME aus der gesellschaftlichen Perspektive betrugen EUR 32560±44270 pro Patient. Die jahrlichen Krankheitskosten bei Patienten mit ALS (EUR 54940±57190) waren signifikant hoher als bei Patienten mit FSH (EUR 18040±20780, p

The immunoproteasome is upregulated by disease, oxidative stress, and inflammatory cytokines, suggesting an expanded role for the immunoproteasome in stress signaling that goes beyond its canonical role in generating peptides for antigen presentation. The signaling pathways that are regulated by the immunoproteasome remain elusive. However, previous studies suggest a role for the immunoproteasome in the regulation of PTEN and NF-κB signaling. One well-known pathway upstream of NF-κB and downstream of PTEN is the Akt signaling pathway, which is responsible for mediating cellular survival and is modulated after optic nerve crush (ONC). This study investigated the role of retinal immunoproteasome after injury induced by ONC, focusing on the Akt cell survival pathway. Retinas or retinal pigment epithelial (RPE) cells from wild type (WT) and knockout (KO) mice lacking either one (LMP2) or two (LMP7 and MECL-1) catalytic subunits of the immunoproteasome were utilized in this study. We show that mRNA and protein levels of the immunoproteasome subunits are significantly upregulated in WT retinas following ONC. Mice lacking the immunoproteasome subunits show either a delayed or dampened apoptotic response as well as altered Akt signaling, compared to WT mice after ONC. Treatment of the RPE cells with insulin growth factor-1 (IGF-1) to stimulate Akt signaling confirmed that the immunoproteasome modulates this pathway, and most likely modulates parallel pathways as well. This study links the inducible expression of the immunoproteasome following retinal injury to Akt signaling, which is important in many disease pathways.

PURPOSE. Retinal pigmented epithelial (RPE) cells maintain the blood–retinal barrier, sustain retinal photoreceptor cell health and function, and may play a role in ocular immune privilege. If RPE immunomodulatory activities were antigen specific, their expression would require antigen presentation. In a study of antigen processing and major histocompatibility complex (MHC) class I–restricted presentation by RPE cells, the cells’ sensitivity to the activity of cytotoxic T lymphocytes (CTLs) was determined. METHODS. RPE was cultured, with and without proinflammatory cytokines and antigen, followed by the addition of -galactosidase (-gal)–specific CTLs. Cytotoxic activity was measured by the CTL-dependent activation of caspase-3 in the RPE. Sensitivity to the CTLs was used to evaluate the activity of pathways of antigen processing and presentation using an antigen (-gal) that was either applied to or expressed in RPE. RESULTS. RPE cells were sensitive targets for activated CTLmediated killing in vitro only if prepulsed with cognate peptide, or if -gal-expressing RPE was pretreated to induce upregulation of immunoproteasome. Activated CTLs induced apoptosis in RPE within 3 hours of coculture with antigenpositive RPE monolayers. Application of CTLs in a resting state to antigen-positive RPE led to their activation in the absence of exogenous antigen-presenting cells (APCs). This antigen-dependent activation and killing required 24 hours of co-incubation of RPE with resting CD8 T cells specific for -gal. Although RPE cells are highly phagocytic, functional evidence for processing that allowed phagocytosed antigens to load into class I MHC was not detected. RPE was minimally sensitive to bystander killing by activated CTLs. CONCLUSIONS. Although there are many reports of T-cell inhibition by RPE, we found that CTLs efficiently killed RPE cells by induction of apoptosis in an antigen-dependent manner. The survival of RPE in the face of extensive CTL destruction of adjacent photoreceptor cells in vivo appears to be based on their insensitivity to injury via bystander mechanisms. (Invest Ophthalmol Vis Sci. 2006;47:5385–5394) DOI:10.1167/ iovs.06-0636

La mutación p.thr124Met en la proteína mielina cero (MPZ) causa la enfermedad de Charcot-Marie-Tooth tipo 2J, una neuropatía periférica con síntomas adicionales como alteraciones pupilares y sordera. Se ha observado en varias familias alrededor del mundo, originarias de Alemania, Bélgica, Japón, Italia y Norteamérica, entre otras. Aquí reportamos a pacientes centroamericanos provenientes de Costa Rica que acarrean esta mutación. Se realizaron análisis clínico, electrofisiológico y molecular de pacientes y controles, incluyendo secuenciación del gen y de marcadores ligados a éste. Estos pacientes comparten casi por completo el haplotipo con dos pacientes belgas no emparentados. Como resultado del análisis de los haplotipos, basado en diez marcadores (siete SNPs, dos microsatélites y un elemento poli-A intrónico), se sugiere que se ha dado un efecto fundador en la migración de este alelo.

Binding of ligands to the receptor for advanced glycation end products (RAGE) results in activation of the transcription factor nuclear factor kappa B (NF-(kappa)B) and subsequent expression of NF-(kappa)B-regulated cytokines. This has been shown to be a relevant pathomechanism in diabetic polyneuropathies (PNP). To determine whether this pathway may contribute to the pathogenesis of PNP due to impaired glucose tolerance (IGT) we performed a pilot study to demonstrate the presence of the RAGE ligand N (epsilon)-(Carboxymethyl)lysine (CML), the receptor itself and N-(kappa)B in sural nerve biopsies of 4 patients with IGT-related PNP. Biopsies of either 4 patients with diabetic PNP and with Charcot-Marie-Tooth disease (CMT) I and II served as positive and negative controls, respectively. In IGT-related PNP and diabetic PNP, CML, RAGE, and NF-(kappa)B was found in the perineurium, epineurial vessels and in part in endoneurial vessels. CMT patients showed, if any, only weak staining for one or the other antigen. These data suggest that activation of the RAGE pathway may be one of the first steps in the pathogenesis of PNP even before chronic hyperglycemia occurs.

Recently we showed that donor-specific tolerance to MHC-matched islet allografts in diabetic NOD mice could be induced by simultaneous islet and bone marrow transplantation. Mononuclear cell infiltration surrounding the islets was also found in tolerated grafts. In this study, we compared gene expression in the tolerated and rejected islet grafts by using Affymetrix Murine U74A oligonucleotide arrays. To confirm the results of microarray analysis, we performed real-time PCR and RNase protection assay on selected genes. Of over 12,000 genes studied, 57 genes were expressed at consistently higher levels in tolerated islet grafts, and 524 genes in rejected islet grafts. Genes from a variety of functional clusters were found to be different between rejected and tolerated grafts. In the rejected islet grafts, a number of T-cell surface markers and of cytotoxicity-related genes were highly expressed. Also in the rejected grafts, a number of cytokines and chemokines and their receptors were highly expressed. The differential expression of selected genes found by microarray analysis was also confirmed by real-time PCR and RNase protection assay. Our results indicated that gene microarray analysis can help us to detect gene expression differences representative of the biologic mechanisms of tolerance and rejection.

Clinically, amyotrophic lateral sclerosis (ALS) usually presents as a pure motor system disorder, whereas oculomotor and sphincter muscle control of the anus and the bladder appear to be spared. Previously, a lacking expression of calcium binding proteins (CBPs) was demonstrated in vulnerable motor neurons in contrast to spared neuronal populations, e.g., the motor neurons of the cranial nerve III (NO) and the Onufrowicz nucleus (ON), suggesting a potential role of CBPs in the selective motoneuronal vulnerability in ALS. The annexins comprise a multigene family of CBPs, constituting a significant amount of total cellular protein and presumably involved in calcium-homeostasis and intracellular calcium-regulated pathways. We immunohistochemically investigated the expression patterns of annexins A1, A2, A4, A5, A6, and A7 in spinal cord and midbrain tissues from 24 ALS patients and 5 age-matched controls to test the hypothesis that annexins also contribute to the selective vulnerability in ALS. There was no difference in the expression patterns of ALS cases and normal controls. Annexin A1 was expressed in ependymal cells and motor neurons. Annexin A2 could be detected in ependymal and endothelial cells and motor neurons. Annexins A4 and A5 were found in both ependymal and glial cells, whereas annexin A6 was strongly expressed in motor neurons. Annexin A7 was totally absent from central nervous system tissue. A contribution of annexins to the selective vulnerability in ALS could not be derived from our results.

Glial cell cytoplasmic inclusions were identified in a case of spinocerebellar ataxia type 2. These have not been reported before. The inclusions were found in low frequency in the dentate nucleus, cerebellar white matter, pontine transverse fibres, and the inferior olivary nucleus. They were of variable size and shape and expressed ubiquitin, thus resembling glial cytoplasmic inclusions in multiple system atrophy. However, their immunohistochemical profile was different as they did not show immunoreactivity for either tau protein or alpha-synuclein. There was no evidence of expanded polyglutamine tracts in these inclusions, which also failed to label with silver stains. As in many other neurodegenerative diseases, in spinocerebellar ataxia type 2 there may be pathogenic contributions of glial cells other than the common astrogliotic response to neuronal damage.

Charcot-Marie-Tooth disease (CMT) comprises a heterogeneous group of hereditary motor and sensory peripheral neuropathies. The autosomal recessive axonal form of CMT (ARCMT2) is rare. Eight patients of a large consanguineous family of Spanish ancestry in Costa Rica were diagnosed with ARCMT2B; previous genetic studies of this family revealed linkage to chromosome 19q13.3. The clinical and electrophysiological features of these patients are reported. All patients presented with a symmetric motor and sensory neuropathy, which was more pronounced in the lower limbs. Further, distal muscle wasting and impaired deep tendon reflexes were found. Age at onset was between 26 and 42 years, and the disease duration ranged from 2 to 19 years. Electrophysiological studies revealed a primary axonal degenerative process. The clinical characteristics of this family differed in several aspects from previously reported families with ARCMT2.

Polyneuropathies are common disorders of the peripheral nervous system. Early diagnosis and therapy enables to stop the progression of the polyneuropathy and to ameliorate polyneuropathic symptoms in most cases. Clinical examination is sufficient to diagnose polyneuropathy. However, to reveal the etiology of a polyneuropathy additional diagnostic procedures are necessary. The general practitioner should recognize the signs and symptoms of a polyneuropathy and start necessary investigations. If the etiology of the polyneuropathy is revealed specific therapy can be started. Furthermore, polyneuropathic symptoms can be ameliorated independently of the underlying cause.

Objectives : There is evidence of impaired cardiovascular autonomic control and reduced baroreflex sensitivity in patients with amyotrophic lateral sclerosis (ALS). A compromised baroreflex–chemoreflex interaction might result in inadequate responses to chemoreflex activation with progressive hypercapnia and hypoxia and contribute to early fatalities. This study was performed to assess cardiovascular and ventilatory responses to hypercapnic and hypoxic stimulation in ALS patients with impaired baroreflex function. Patients and methods : In 15 ALS patients with previously demonstrated baroreflex dysfunction and in 15 age-matched controls, we compared electrocardiographic RR-interval (RRI), systolic blood pressure (SBP) and minute ventilation (VE) during normal ventilation and during selective progressive hypoxia and hypercapnia. Results : Ventilatory and RRI responses to hypoxic and hypercapnic stimulation as well as SBP responses to hypercapnia did not differ between patients and controls. In contrast, hypoxia induced a significant SBP increase in patients only. Conclusions : The normal ventilatory and RRI responses to chemoreflex activation suggest intact afferent chemoreflex function. The hypertensive response to hypoxia might be due to a compromised interaction with the baroreflex. Avoiding hypoxic episodes might reduce the risk of cardiovascular crisis in ALS patients.

Objectives: Amyotrophic lateral sclerosis (ALS) is a fatal disease with unique demands on patients and carers. Patients and methods: The total burden of care and burden components in 37 ALS carers were measured using validated questionnaires. Furthermore, influencing factors (functional impairment of the patient, additional carers, participation in support groups) were assessed. Results: The mean total burden of care for ALS was low compared with dementia, mixed neuropsychiatric and internal diseases, but was correlated with functional impairment ( P = 0.003). The main burden components were 'personal and social restrictionsfland ’physical and emotional problems‘. Problem behaviour of the patients was low in general, but was higher in carers participating in support groups ( P = 0.002). Carers supported by additional carers had higher strain. Conclusion: The low burden of ALS carers may be caused by the low incidence of problem behaviour in ALS patients. However, if problem behaviour exists, carers participate more often in support groups, indicating the need for assistance. The burden of care increases with the functional impairment. Support for the carers has to start sooner.

Vasculitic neuropathies are immune mediated diseases of the peripheral nervous system, in which inflammation of the blood vessels causes damage to the nerves. We distinguish neuropathies associated with primary and secondary systemic vasculitis, with rheumatic diseases, with malignant disorders, drug-induced vasculitis and the non-systemic vasculitic neuropathies (NSVN). The typical clinical picture consists in an asymmetric or multifocal, painful sensorimotor neuropathy with an acute, subacute or chronic course and acute relapses. Neurophysiology reveals an active, asymmetric, axonal sensorimotor neuropathy. The disorders usually respond to immunosuppressive treatment. A diagnosis of definite vasculitis can be made with evidence of vasculitis in a biopsy specimen. The absence of positive morphological evidence, however, does not exclude the diagnosis. There is no single laboratory test that can prove or exclude vasculitis, in NSVN even an elaborate panel of blood tests can show normal findings. Systemic vasculitis has an incidence of 4/100,000 per year and, untreated, has a poor prognosis, which is greatly improved by the use of immunosuppressive treatment. The prognosis of NSVN is generally better, although many patients need long term immunosuppression. Current treatment recommendations for vasculitic neuropathies are presented.

artículo -- Universidad de Costa Rica. Instituto de Investigaciones en Salud, 2003 Abstract. Charcot-Marie-Tooth disease type IB (CMT 1B) is caused by mutations in the gene coding for peripheral myelin protein zero (MPZ, P0) that plays a fundamental role in adhesion and compaction of peripheral myelin. Here we report a Costa Rican family with a hereditary peripheral neuropathy due to a novel Tyr145Ser MPZ mutation. Four family members were heterozygously affected; two siblings of two heterozygous carriers were homozygous for this mutation. On neurological examination the heterozygous parents and their homozygous children both showed distal sensory deficits. The mother and the siblings displayed impaired deep tendon reflexes and mild sensory ataxia. The homozygous individuals were more severely affected with an earlier age of onset, distal motor weakness, and pupillary abnormalities. Electrophysiological studies revealed both signs of demyelination and axonal nerve degeneration. The sural nerve biopsy of one sibling showed thinly myelinated nerve fibers, onion bulb formation, and clusters of regenerating fibers. On electron microscopy axonal degeneration and decompaction of inner myelin layers were found. This Costa Rican family shows phenotypic variability depending on the homozygous or heterozygous state of the Tyr145Ser mutation carriers. info:eu-repo/grantAgreement/Universidad de Costa Rica/Instituto de Investigaciones Psicológicas //// UCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias de la Salud::Instituto de Investigaciones en Salud (INISA)

This study describes the distribution and identity of annexin-1 positive cells in the central nervous system in patients with multiple sclerosis (MS). Glucocorticoid-inducible, anti-inflammatory properties have been ascribed to annexin-1, a member of a family of calcium-binding proteins that are referred to collectively as annexins. We have found annexin-1 to be spatially associated with active MS lesions and demonstrated a stage-dependent expression of annexin-1 in MS plaques. All of the most important pathogenetically involved cells of MS lesions showed a strong annexin-1 reactivity. Both correlation analysis and double staining procedures suggested annexin-1 expression in macrophages and perivascular lymphocytes, where a cytoplasmic reactivity was displayed, whereas in activated, gemistocytic astrocytes it was also concentrated close to the plasma membrane. Although the exact roles of annexin-1 in this setting are still to be determined, a possible contribution to anti-inflammatory processes might be suggested.

Background. Human type 1 diabetes is associated with defects in the hematopoietic stem cells. Simultaneous donor islet and bone marrow transplantation may be an ideal therapeutic approach for inducing tolerance to islet allogeneic antigens and restoring self-tolerance to islet autoimmune antigens. Methods. Using a nonobese diabetic (NOD) mouse model of human type 1 diabetes, we investigated whether tolerance to MHC-matched allogeneic islet grafts from male nonobese diabetes-resistant (NOR) donors can be induced in female NOD recipients by simultaneous islet and bone marrow transplantation under fludarabine phosphate-based nonmyeloablative and irradiation-free conditioning therapy. Donor-specific chimerism in the peripheral blood of tolerant mice (n=7) was measured by semiquantitative polymerase chain reaction for a male-specific marker (SRY). Results. Donor-specific tolerance to NOR islet grafts was induced in all diabetic NOD mice after simultaneous islet and bone marrow transplantation and treated with fludarabine phosphate, cyclophosphamide, anti-mouse lymphocyte serum, and rapamycin. At 100 days and 200 days after transplantation, the average percentage of male NOR marker in DNA derived from the peripheral blood of NOD recipients that had long-term islet graft survival was over 10%. Conclusion. Our data suggest that this approach may induce donor-specific tolerance in clinical islet transplantation and living-related donor solid organ transplantation.

Hematopoietic macrochimerism, established by bone marrow transplantation, can be used as an approach for treating autoimmune disease and inducing transplant tolerance. In this study, we investigated whether a stable, high level of fully MHC-mismatched hematopoietic macrochimerism can be induced by using irradiation-free protocols, and whether rapamycin and T cell costimulatory blockades (anti-CD40L monoclonal antibody (mAb) and CTLA4Ig) as post-transplant treatment promote bone marrow engraftment. Donor-specific blood transfusion (DST), anti-lymphocyte serum (ALS), busulfan, and cyclophosphamide were given pretransplantation. Balb/c (H-2(d)) bone marrow cells, at a dose of 4 x 10(7), were infused into each C57BL/6 mouse (H-2(b)). Rapamycin, anti-CD40L mAb, and CTLA4Ig were then administered, either alone or in combination. Without ALS or busulfan and cyclophosphamide, macrochimerism can only rarely be induced. Donor-specific transfusion (DST) enhances induction of hematopoietic macrochimerism. Rapamycin, anti-CD40L mAb and CTLA4Ig, alone or in combination, induce a stable and high level of hematopoietic macrochimerism. In the chimeric mice, donor-derived cells were detected in all lymphohematopoietic tissues and donor-specific tolerance was induced in vitro. We conclude that a stable and high level of fully MHC-mismatched hematopoietic macrochimerism can be induced in mice after transplanting a single modest dose of bone marrow cells without irradiation. Rapamycin and T cell costimulatory blockade as post-transplant treatment promote bone marrow engraftment.

This is the case of a 41 year old man, suffering general weakness and elevated liver enzymes, sensitive to a treatment with riboflavin and coenzyme Q 10 . Tandem mass spectroscopy and molecular analysis reveal a multiple acyl-CoA-dehydrogenase deficiency (MADD) with two novel heterozygote missense mutations of the EFTDH gene.

In some patients with amyotrophic lateral sclerosis (ALS), T2-weighted and proton-density-weighted magnetic resonance imaging (MRI) shows hyperintense or hypointense signals at the corticospinal tract. Fluid-attenuated inversion recovery (FLAIR) sequences increase the sensitivity of MRI to detect cortical and subcortical tissue changes. In 31 ALS patients and 33 controls, we studied the frequency and the extent of signal abnormalities in FLAIR images compared to T2-, T1- and proton-density-weighted images. Hyperintense signals at the corticospinal tract were significantly more frequent in FLAIR images than in all other tested sequences. In FLAIR images of ALS patients only, distinct hyperintense signals at the subcortical precentral gyrus (five patients), the centrum semiovale (eight patients), the crus cerebri (nine patients) and the pons (four patients) as well as mild hyperintense signals in the medulla oblongata (three patients) were seen. More frequently, but not exclusively in ALS patients, FLAIR images showed mild hyperintense signals at the subcortical precentral gyrus (15 patients vs. 1 control). Quantitative analysis confirmed the significant difference between ALS patients and controls at the subcortical precentral gyrus in FLAIR images. In T1-weighted images, the corticospinal tract at the capsula interna was hypointense in significantly more controls than ALS patients. Also this difference was confirmed in the quantitative analysis. Similar to previous results, MR image alterations did correlate poorly to clinical data of upper motor neuron affliction.MR images of the head, including FLAIR images, provide additional information regarding corticospinal tract involvement in ALS patients. Because of an overlap with physiological findings, they have to be interpreted cautiously, with the exception of hyperintense signals at the subcortical precentral gyrus.