Bruno Voss

Homozygous mutations in caveolin-3 cause a severe form of rippling muscle disease

Heterozygous missense mutations in the caveolin‐3 gene (CAV3) cause different muscle disorders. Most patients with CAV3 alterations present with rippling muscle disease (RMD) characterized by signs of increased muscle irritability without muscle weakness. In some patients, CAV3 mutations underlie the progressive limb‐girdle muscular dystrophy type 1C (LGMD1C). Here, we report two unrelated patients with novel homozygous mutations (L86P and A92T) in CAV3. Both presented with a more severe clinical phenotype than usually seen in RMD. Immunohistochemical and immunoblot analyses of muscle biopsies showed a strong reduction of caveolin‐3 in both homozygous RMD patients similar to the findings in heterozygous RMD. Electron microscopy studies showed a nearly complete absence of caveolae in the sarcolemma in all RMD patients analyzed. Additional plasma membrane irregularities (small plasmalemmal discontinuities, subsarcolemmal vacuoles, abnormal papillary projections) were more pronounced in homozygous than in heterozygous RMD patients. A stronger activation of nitric oxide synthase was observed in both homozygous patients compared with heterozygous RMD. Like in LGMD1C, dysferlin immunoreactivity is reduced in RMD but more pronounced in homozygous as compared with heterozygous RMD. Thus, we further extend the phenotypic variability of muscle caveolinopathies by identification of a severe form of RMD associated with homozygous CAV3 mutations. Ann Neurol 2003

Expression of tumor necrosis factor-α and transforming growth factor-β1 in cerebrospinal fluid cells in meningitis

Abstract Meningitis is an acute inflammatory disease of the pia and arachnoid and the fluid in the subarachnoid space, in which a participation of cytokines can be expected. While tumor necrosis factor-alpha (TNFα) promotes inflammatory reactions, transforming growth factor-β1 (TGFβ1) has antagonistic effects and suppresses the inflammation in the subarachnoid space. We investigated the protein concentration and mRNA expression of TNFα and TGFβ1 in cerebrospinal fluid (CSF) by ELISA and intracellularly by non-radioactive in situ hybridization in 23 patients with bacterial or viral meningitis. A higher amount of both cytokines on protein and mRNA level, especially of TNFα, could be detected in bacterial infection. While an imbalance of both cytokines with a preponderance of TNFα-compared to TGFβ1-mRNA was visible in CSF cells of patients with bacterial meningitis, a balance of TNFα- and TGFβ1-mRNA or a higher expression of TGFβ1-mRNA could be detected in viral meningitis. In the acute phase of the disease neutrophil granulocytes expressed more TNFα- and TGFβ1-mRNA than lymphocytes and monocytes/macrophages, while these cell types were dominating the cytokine synthesis during the healing phase. These data indicate that immunomodulatory mechanisms take place in the CSF compartment itself, regulated by CSF cells in different but specific ways. In addition, TGFβ1 seems to be involved in the down-regulation of the inflammatory activity and to be one factor in the cytokine network, which could contribute to a lower rate of complications and positive outcomes. Moreover this study favors the possibility to monitor the immunomodulatory mechanisms by non-radioactive in situ hybridization.

Detection of transforming growth factor beta1 mRNA in cerebrospinal fluid cells of patients with meningitis by non-radioactive in situ hybridization

Meningitis is a serious disease mostly caused by viral or bacterial infections. In complicated cases it may lead to brain damage and death. The infection and cell damage result in a cellular and immunological response. Following this, a high secretion of cytokines can be expected. Cytokines, especially tumour necrosis factor alpha (TNF-alpha) and interleukin-1 (IL-1), promote the inflammatory reactions in the subarachnoid space. Transforming growth factor beta1 (TGF-beta1) has antagonistic effects on TNF-alpha and IL-1-mediated processes. Therefore, it suppresses inflammatory reactions. To observe the expression of TGF-betal in transcellular signalling in the inflammatory processes of meningitis, we investigated TGF-betal mRNA in cells in the cerebrospinal fluid of three patients with meningitis by non-radioactive in situ hybridization. All patients fulfilled the usual clinical criteria of meningitis. In one caseNeisseria menigitidis could be identified as the pathogenic agent. In the remainder, no agent could be isolated. In all cytological preparations of the cerebrospinal fluid of these patients a high level of TGF-betal mRNA was detectable in the cell populations. It was possible to distinguish between the different cell types of the cerebrospinal fluid and to attach the mRNA expression to them. On the one hand, this makes it possible to investigate pathogenesis and defence mechanisms in bacterial and aseptic meningitis on a cellular level; on the other hand, it may open new perspectives in the control of disease development, prognosis, diagnosis and supporting therapy.

Homing of transplanted bone marrow cells in livers of Schistosoma mansoni-infected mice

Elkhafif N, Voss B, Hammam O, Yehia H, Mansy S, Akl M, Boehm S, Mahmoud S, El Bendary O, El Fandy G. Homing of transplanted bone marrow cells in livers of Schistosoma mansoni‐infected mice. APMIS 2010; 118: 277–87.

A Comparative Study of Chemically Induced DNA Damage in Isolated Nasal Mucosa Cells of Humans and Rats Assessed by the Alkaline Comet Assay

Single-cell microgel electrophoresis (comet) assay was used to study genotoxic effects in human nasal mucosa cells and rat nasal and ethmoidal mucosa cells in vitro. Human cells were obtained from tissue samples of 10 patients (3 females/7 males), who underwent surgery (conchotomy) for treatment of nasal airway obstruction. Rat nasal mucosa cells were derived from male Sprague-Dawley rats. Cells were exposed for 1 h to either N-nitrosodiethanolamine (NDELA), epichlorohydrin (EPI), 1,2-epoxybutane (EPB), ethylene dibromide (EDB), or 1,2-dibromo-3-chloropropane (DBCP). Dimethyl sulfoxide (DMSO) was used as negative control. Alkaline comet assay was performed according to a standard protocol and DNA damage was quantified as Olive tail moment using image analysis system. All test substances induced an increase in DNA damage in human and rat cells. The absolute amount of DNA damage in rat nasal mucosa cells was usually higher than in ethmoidal mucosa cells. Human nasal mucosa cells were found to be less sensitive than rat mucosa cells to the genotoxic activities of DBCP (lowest effective concentration in human cells [LEChuman]: 1.5, in rat cells [LECrat]: 0.01 mM) and NDELA (LEChuman: 25, LECrat: 12.5 mM), whereas EPB-treated cells were almost equal (LEChuman and LECrat 0.78 mM). NDELA induced a marked concomitant cytotoxicity. For EPI (LEChuman and LECrat: 0.097 mM) and EDB (LEChuman: 0.195, LECrat: 0.048 mM), pronounced interindividual differences were observed in human samples.

Mineral Fibre-Related Bronchial Lesions

The bronchopathogenic potential of crocidolite asbestos and four man-made mineral fibres have been compared. Groups of rats received, respectively, a single intratracheal instillation of UICC crocidolite asbestos, Rockwool 115-4, Carborundum CEF 100, Basaltwool-Isolyth, or Mineralwool-Isolyth dusts into the right lower lobe. At intervals, from 2 days up to 6 months after the treatment, lung histology was performed on animals from each group. Bron chial effects of crocidolite asbestos and the different man-made mineral fibres revealed more quantitative than qualitative differences. In accordance with the literature, inflammatory and regressive lesions were found to dominate the early phase of reaction. Later, adenoma-like structures developed as a result of two different pathomechanisms: (1) Bifurcational, central interception of long fibres and consecutive scarring granulomas induced polypous-papillomatous mucosal proliferations and partition of the bronchus into small, ciliary epithe lial lined lumina. (2) In the chronic phase of reaction, budding and prolifera tion of the mucosal cells resulted in many small lumina in the wall and round the bronchi, without any scar formation. The increased dividing activity in the mucosa, the abnormalities of the secretion, the metaplasia and local prolifera tion of the epithelium, basement membrane disintegration, and changes of the extracellular matrix are typical of mucosal preneoplasias. As a result of the different lesions, first of all the adenomatoid proliferations, and then focal and irreversible remodelling of the bronchial tree had occurred by the end of the experiments.

Airway responsiveness of rabbits after exposure to 2-octyl dodecanol

Cooling lubricants are used in the metal industry during drilling or turning. Vapors and aerosols of these lubricants are suspected to induce airway hyperresponsiveness (AHR) in exposed workers. In a previous study the authors demonstrated that water-soluble lubricants induce AHR after acute exposure of rabbits to concentrations near the German MAK value (10 mg/m(3)). In the present investigation the influence of a fatty alcohol as special non-water-soluble cooling lubricant was examined to determine its influence on airway responsiveness (AR). The effects of an aerosolized non-water-soluble lubricant (40, 90, and 220 mg/m(3)) on AR to acetylcholine in a rabbit model were studied. Lubricant atmosphere analysis was performed with infrared spectroscopy. Before exposure, after 2 and 4 hours of application, AR to aerosols from 0.2 and 2% acetylcholine was tested. Basal airway and cardiovascular parameters as well as blood gases did not change during exposure. Lubricant aerosol concentration of 40 and 220 mg/m(3) for 4 hours did not significantly alter AR. Inhalation of 90 mg/m(3) lubricant increased contractile response to ACH significantly. In contrast to formerly investigated water-soluble cooling lubricants, the examined non-water-soluble lubricant did not increase AR in concentrations near the MAK; however, in higher concentrations a significant (p<.05) increase was obtained.