[Stem cell transplantation for multiple sclerosis. Hamburg experiences and state of international research]. / Stammzelltransplantation bei Multipler Sklerose. Hamburger Erfahrungen und internationaler Forschungsstand.

BACKGROUND: Autologous hematopoietic stem cell transplantation (aHSCT) is still not the standard treatment for highly inflammatory multiple sclerosis (MS). Even though randomized controlled trials are lacking, predictors for treatment response have been established. Since 2007, ten patients have received aHSCT in Hamburg. OBJECTIVE: To present observational data from patients treated in Hamburg and a review of the literature. METHODS: Descriptive statistics were used for evaluating the course of the expanded disability status scale (EDSS) as a measure for clinical outcome, magnetic resonance imaging (MRI) and neuropsychology. New gadolinium and T2-MRI uptake lesions per scan were compared. In addition, a systematic review of the currently available literature was performed. RESULTS: The Hamburg series can be divided in two groups, one group including four patients with chronic progressive MS with low inflammatory activity (median EDSS = 6.25, 0.5 relapses per year, no gadolinium-enhancing lesions) and the other group including six patients with mild to moderate disability, relapses and inflammatory activity (median EDSS = 4.25, 1 relapse per year, 2 gadolinium-enhancing lesions). The median follow-up was 2.4 years. While the first group did not seem to benefit from aHSCT, an improvement in five out of six patients was observed in the second group. New T2 lesions occurred within the first 6 months but gadolinium-enhancing lesions were not observed (p < 0.05). A systematic literature search identified a higher efficacy of aHSCT in younger, less disabled MS patients with inflammatory activity, similar to the findings from Hamburg. CONCLUSION: Cohort reports describe aHSCT as a safe and efficient treatment option in highly inflammatory MS. Based on these data aHSCT seems to be a reasonable option in selected patients with highly inflammatory MS but a randomized controlled trial is warranted.

[Autoimmune synaptic encephalopathies]. / Autoimmune synaptische Enzephalopathien.

Antibody-associated limbic encephalitis was usually seen as a paraneoplastic syndrome where the antibodies would target intracellular proteins. However, recent reports challenged this idea and described antibodies that target synaptic proteins expressed on the cell surface. These antibodies are not necessarily linked to tumors and should be regarded as a distinct entity of different autoimmune diseases. They are of direct clinical relevance since their binding to their target antigen is likely the cause of the clinical symptoms and, therefore, immune treatment often results in a beneficial outcome. Tests which differentiate these antibodies are now available in specialized laboratories.

Linewidth reduction in a large-smile laser diode array.

We present theory and simulations for a spectral narrowing scheme for laser diode arrays (LDAs) that employs optical feedback from a diffraction grating. We calculate the effect of the so-called smile of the LDA and show that it is possible to reduce the effect by using a cylindrical lens set at an angle to the beam. The scheme is implemented on a 19-element LDA with smile of 7.6 microm and yields frequency narrowing from a free-running width of 2 to 0.15 nm. The experimental results are in good agreement with the theory.

The innate immune response in the central nervous system and its role in glioma immune surveillance.

The innate immune system encompasses natural killer (NK) cells, macrophages and granulocytes, the complement system and antimicrobial peptides. Recognition pathways of the innate immune system include microbial non-self recognition, missing-self recognition and induced- self recognition. The central nervous system (CNS) participates in responses of the innate immune system. However, immune inhibitory and anti-inflammatory mechanisms physiologically outbalance and counteract immune activity and thereby limit immune-mediated tissue damage in the brain. Human gliomas appear to take advantage of this immunosuppressive milieu. Moreover, glioma cells themselves interfere with anti-tumor immune responses by expressing immune inhibitory cell surface molecules, such as HLA-G, or by releasing soluble immunosuppressants such as transforming growth factor (TGF)-beta. Yet, although glioma cells exhibit all cellular features of malignancy, these tumors very rarely metastasize outside the brain, raising the possibility of immune-mediated control of these cells outside, but not inside, the brain. Accordingly, activating the innate immune system by forcing glioma cells to express danger signals such as NKG2D ligands is a promising strategy of immunotherapy for these tumors.

Release of endogenous anti-inflammatory complement regulators FHL-1 and factor H protects synovial fibroblasts during rheumatoid arthritis.

Rheumatoid arthritis is a chronic inflammatory disease of unknown aetiology predominantly affecting cells and tissues of synovial joints. Here we show that the two important complement regulators FHL-1 and factor H play a protective anti-inflammatory role in rheumatoid arthritis. Expression analyses at the mRNA- and protein level show in vitro expression and secretion of both regulators by synovial fibroblasts derived from patients with rheumatoid arthritis. Similarly the two regulators are synthesized in vivo in diseased synovial tissue, and in particular synovial lining cells express high levels of FHL-1. The anti-inflammatory role of these regulators in rheumatoid arthritis is highlighted by their induction with IFN-gamma and dexamethasone, whilst the pro-inflammatory cytokine TNF-alpha had no effect. Transient transfection experiments with various FHL-1/factor H promoter-luciferase reporter constructs into cells of distinct origin show independent cell and tissue specific promoter regulated transcription of these two regulators. The inducible expression, specifically of FHL-1 has physiological consequences. By binding directly to surfaces the released proteins protect cells from inflammatory damage and complement-mediated cell lysis. This study shows a novel protective and anti-inflammatory role of the two important complement regulators FHL-1 and factor H in rheumatoid arthritis and suggests a disease controlling role of the two proteins.

Influence of TachoComb in comparison to local hemostyptic agents on epidural fibrosis in a rat laminectomy model.

This animal experimental study was designed to examine the effects of TachoComb, a fixed combination of collagen with tissue adhesive, as an interposition membrane on the development of spinal epidural fibrosis in comparison to other hemostyptic materials. In 10 Wistar rats, four laminectomies were performed at lumbar and sacral vertebrae. Alternately, a piece of TachoComb, Spongostan, or Tabotamp was placed into each laminectomy site. One laminectomy site served as an empty control (n = 10). 8 weeks later, the animals were sacrificed, and the spinal column including surrounding muscle tissue was removed en bloc from each rat and fixed in formaldehyde. After decalcification and staining the specimens were graded by a neuropathologist in a blindfold test for severity of epidural fibrosis as "light-moderate" or "marked". Epidural scarring of variable density was seen in all laminectomy sites. Light epidural fibrosis, without any adhesion to dura, as only noted in cases after application of TachoComb (n = 4/10) and Spongostan (n = 1/10). All other slices showed marked epidural fibrosis with dura adherence regardless of the implanted material. Statistical analysis revealed significantly lower epidural fibrosis after application of TachoComb compared to all other groups (p < 0.05). In this series, TachoComb is more effective in reducing the epidural fibrosis than Spongostan, and Tabotamp. However, complete prevention of scar tissue formation was not achieved.

Amyotrophic lateral sclerosis: evidence for intact hepatocyte growth factor/met signalling axis.

Hepatocyte growth factor (HGF) is a secreted cytokine which is expressed in the central nervous system (CNS) together with its specific receptor MET. Since HGF exerts strong neurotrophic activity including motoneurons, we have further analysed whether the HGF/MET axis is defective in patients with amyotrophic lateral sclerosis (ALS). Intrathecal HGF-secretion was measured in cerebrospinal fluid (CSF) from patients with amyotrophic lateral sclerosis and in controls without neurological diseases using a specific sandwich immunoassay (ELISA). MET-expression was analysed by immunohistology in spinal cord cross-sections of ALS patients and unaffected controls. The HGF concentrations in CSF were moderately but significantly increased in ALS patients compared to healthy controls (580 pg/ml vs 348 pg/ml). MET-protein was detectable in spinal cord motoneurons of patients with ALS as well as unaffected controls. The data demonstrate that ALS does not show a lack of the trophic signalling axis, HGF/MET, suggesting that the signalling system itself is not affected. The moderate increase in HGF-secretion may represent a compensatory effect.

Subacute encephalopathy with seizures in chronic alcoholism (SESA syndrome).

Report of a case of SESA syndrome: a rare CNS complication of chronic alcoholism, known since 1981 and characterized by epileptic seizures, multiple and reversible neurological deficits, as well as PLEDs in the EEG. The MRI showed enhanced occipital signals in the T2-weighted sequence, which resolved together with the clinical findings.

Effects of electrical stimulation of the Gasserian ganglion on regional cerebral blood flow after induced subarachnoid hemorrhage in pigs evaluated by 99mTc-HMPAO-SPECT.

It could be demonstrated that cervical spinal cord stimulation increases cerebral blood flow. The effects of electrical stimulation of the trigeminal ganglion in the acute phase of SAH in pigs were investigated. The experiments were carried out on 11 domestic pigs divided in two groups (group I: SAH [n = 5]; group II: SAH and trigeminal stimulation [n = 6]). In all animals a native SPECT was performed. The Gasserian ganglion was exposed for inserting the stimulation electrode. SAH was induced by injecting 10 ml autologous blood through a catheter placed in the suprasellar cistern. 30 minutes after SAH-induction electrical stimulation was started for two hours in group II (2.8-4.5 V, 50 Hz, 300 microseconds). 99mTc-HMPAO (400-540 MBq) was injected intravenously 110 minutes later. In group I 99mTc-HMPAO was applied after the same time interval. 80 minutes later SPECT was performed. Data were processed to calculate the uptake of radioactivity (%/kg tissue weight). The mean values were calculated for the different groups: native animal examination (%/kg tissue weight): 0.6343; group I: 0.468; group II: 0.6533. Comparing the mean values a highly significant difference between group I and group II (p < 0.01) and between native examination and group I (p < 0.01) could be found. No statistical significance could be detected on comparing the left/right-ratio in any ROI. The electrical stimulation of the Gasserian ganglion leads to a significantly increased uptake of 99mTc-HMPAO after induced SAH. Maybe the stimulation of the Gasserian ganglion constitutes a new therapeutic modality treating disturbed rCBF after SAH.

Different regulation of factor H and FHL-1/reconectin by inflammatory mediators and expression of the two proteins in rheumatoid arthritis (RA).

Factor H and the FHL-1/reconectin protein are two human plasma proteins that act as important regulators of the alternative complement pathway. Each protein is encoded by a unique transcript, but both mRNAs are derived from the factor H gene by means of alternative processing. In order to address potential functional differences between the two proteins we analysed their expression in hepatic and non-hepatic cells and studied their regulation by inflammatory mediators. We demonstrate that factor H and FHL-1/reconectin transcripts which are regulated by the same gene promoter and are initiated at the same transcription start site are differently expressed. Expression of the molecules is induced and regulated by the inflammatory mediators interferon-gamma (IFN-gamma) and the anti-inflammatory glucocorticoid dexamethasone. Both factor H and FHL-1/reconectin are expressed and secreted by synovial fibroblasts and are present in synovial fluid derived from patients suffering from rheumatoid or reactive arthritis. The local synthesis in synovial fibroblasts and their induction by IFN-gamma and dexamethasone, but not by tumour necrosis factor-alpha, suggests for each of the two complement regulators a protective role in RA.

Clonal expansions of CD8(+) T cells dominate the T cell infiltrate in active multiple sclerosis lesions as shown by micromanipulation and single cell polymerase chain reaction.

Clonal composition and T cell receptor (TCR) repertoire of CD4(+) and CD8(+) T cells infiltrating actively demyelinating multiple sclerosis (MS) lesions were determined with unprecedented resolution at the level of single cells. Individual CD4(+) or CD8(+) T cells were isolated from frozen sections of lesional tissue by micromanipulation and subjected to single target amplification of TCR-beta gene rearrangements. This strategy allows the assignment of a TCR variable region (V region) sequence to the particular T cell from which it was amplified. Sequence analysis revealed that in both cases investigated, the majority of CD8(+) T cells belonged to few clones. One of these clones accounted for 35% of CD8(+) T cells in case 1. V region sequence comparison revealed signs of selection for common peptide specificities for some of the CD8(+) T cells in case 1. In both cases, the CD4(+) T cell population was more heterogeneous. Most CD4(+) and CD8(+) clones were represented in perivascular infiltrates as well as among parenchymal T cells. In case 2, two of the CD8(+) clones identified in brain tissue were also detected in peripheral blood. Investigation of the antigenic specificities of expanded clones may help to elucidate their functional properties.

Exceptional resistance of human H2 glioblastoma cells to complement-mediated killing by expression and utilization of factor H and factor H-like protein 1.

Of over 20 nucleated cell lines we have examined to date, human H2 glioblastoma cells have turned out to be the most resistant to complement-mediated cytolysis in vitro. H2 cells expressed strongly the membrane attack complex inhibitor protectin (CD59), moderately CD46 (membrane cofactor protein) and CD55 (decay-accelerating factor), but no CD35 (complement receptor 1). When treated with a polyclonal anti-H2 Ab, anti-CD59 mAb, and normal human serum, only 5% of H2 cells became killed. Under the same conditions, 70% of endothelial-like EA.hy 926 cells and 40% of U251 control glioma cells were killed. A combined neutralization of CD46, CD55, and CD59 increased H2 lysis only minimally, demonstrating that these complement regulators are not enough to account for the resistance of H2 cells. After treatment with Abs and serum, less C5b-9 was deposited on H2 than on U251 and EA.hy 926 cell lines. A reason for the exceptional resistance of H2 cells was revealed when RT-PCR and protein biochemical methods showed that the H2 cells, unlike the other cell lines tested, actively produced the soluble complement inhibitors factor H and factor H-like protein 1. H2 cells were also capable of binding human factor H from the fluid phase to their cell surface and promoted the cleavage of C3b to its inactive form iC3b more efficiently than U251 and EA.hy 926 cells. In accordance, anti-factor H mAbs enhanced killing of H2 glioblastoma cells. Taken together, our results show that production and binding of factor H and factor H-like protein 1 is a novel mechanism that these malignant cells utilize to escape complement-mediated killing.

Factor H and disease: a complement regulator affects vital body functions.

Factor H is a multidomain and multifunctional protein. As a complement regulator factor H determines the fate of newly formed C3b and controls formation and stability of C3 convertases both in the fluid phase and on cell surfaces. In addition, this plasma protein displays functions outside complement control as it has been suggested to act as an adhesion protein, to be a ligand for the cellular integrin receptor CR3 (CD11b/CD18) and to display chemotactic activity. Genetic and pathophysiological analyses describe a role for factor H in vital body functions. Depletion or the absence of factor H due to genetic reasons leads to unrestricted C3 consumption. A reduced amount of factor H in plasma or mutations within the factor H gene may lead to glomerulonephritis (type II MPGN) or hemolytic uremic syndrome (HUS). Certain pathogenic organisms have been shown to evade complement attack by binding factor H from the host. Such specific factor H binding components have been demonstrated on the surface of microbes, e.g., Streptococcus pyogenes and Neisseria gonorrhoeae. Here, we summarize the current knowledge how abnormalities in function of the central complement regulator factor H are associated with human diseases.

Positron emission tomography in a case of intracranial hemangiopericytoma.

Due to the low prevalence of hemangiopericytomas (HPCs), data on the biophysiological characteristics of this tumor are rare. Positron emission tomography (PET) demonstrated a sixfold increased uptake of [11C]methionine and hyperperfusion in the HPC, whereas glucose utilization was decreased in this area. This low glucose utilization is in contrast to the high [11C]methionine uptake and the malignancy of these tumors. The characteristics of HPCs in PET described herein for the first time offer additional diagnostic criteria and may help especially to differentiate these tumors from meningiomas.