The definite diagnosis of acute Lyme neuroborreliosis (LNB) requires detection of an increased Borrelia burgdorferi-specific antibody index (AI). The B burgdorferi AI, however, is negative in up to ...20% of patients with early LNB and can remain elevated for years after adequate therapy; both of these factors can make the diagnosis difficult. Recent retrospective studies suggested the chemokine CXCL13 as a potential biomarker for LNB. To evaluate its diagnostic value, we conducted a prospective study.
From March 2008 to August 2009, CSF and serum samples from all patients in whom a B burgdorferi-specific AI was requested (n=692) and CSF analysis revealed CSF pleocytosis (n=192) were included in the study. Because of the low number of patients with untreated LNB, 13 additional retrospectively selected samples of patients with untreated LNB were added. CXCL13 concentrations were measured by ELISA and receiver operating characteristic curves were generated.
CSF CXCL13 was highly elevated in all patients with untreated acute LNB (mean=15,149 pg/mL) compared with that in the patients without LNB (mean=247 pg/mL). At a cutoff of 1,229 pg/mL, the sensitivity of CXCL13 was 94.1%, which is higher than the AI (85.7%). Only 7 patients (5 with a CNS lymphoma and 2 with bacterial meningitis) had a CXCL13 level above the cutoff, resulting in a specificity equal to the AI of 96.1%.
CXCL13 shows high sensitivity and specificity for acute, untreated LNB. This novel marker appears to be helpful in clinically atypical cases and, in particular, in early stages of the disease when the B burgdorferi AI is (still) negative.
Therapy with antibiotics, dexamethasone, and supportive intensive care has improved the prognosis of pneumococcal meningitis, but mortality remains high. Here, we investigated an adjunctive ...combination therapy of the non-bacteriolytic antibiotic daptomycin plus several anti-inflammatory agents to identify the currently most promising adjunctive combination therapy for pneumococcal meningitis.
C57BL/6 mice were infected by injection of pneumococci into the cisterna magna. Treatment was begun 21 h after infection, and consisted of ceftriaxone plus (a) dexamethasone, (b) dexamethasone plus daptomycin, (c) daptomycin, (d) daptomycin plus an anti-IL1 antibody, (e) daptomycin plus roscovitine, or (f) daptomycin plus an anti-C5 antibody. Animals were followed until 45 h after infection. Furthermore, adjunctive daptomycin plus anti-C5 antibodies were assessed in a long-term follow-up.
Adjunctive treatment with daptomycin and an anti-C5 antibody was superior to adjunctive dexamethasone and reduced disease symptoms (clinical score 1.1 ± 1.1 versus 5.0 ± 2.7, p < 0.0083), improved explorative activity (open field test 17.8 ± 8.2 versus 7.4 ± 4.3 crossed fields/2 minutes, p < 0.0083), and reduced hearing impairment (thresholds for click stimulus 96.1 ± 14.7 versus 114.8 ± 9.3 dB SPL, p < 0.0083) in the acute stage. Furthermore, explorative activity (14.4 ± 7.3 crossed fields/2 minutes versus 6.3 ± 7.2, p < 0.05) and cognitive function (t-maze test, exploration time previously unknown alley 72.4 ± 14.3 versus 48.7 ± 25.6%, p < 0.05) was improved at 2 weeks after infection. Treatment with daptomycin plus an anti-IL-1β antibody or roscovitine was not of significant benefit in comparison to adjunctive therapy with dexamethasone.
An adjunctive combination of the non-lytic antibiotic daptomycin plus an anti-C5 antibody was superior to standard therapy with adjunctive dexamethasone in the treatment of pneumococcal meningitis.
Using protein expression profiling, the authors identified an upregulation of the chemokine B lymphocyte chemoattractant (BLC) in the CSF of patients with neuroborreliosis but not in patients with ...noninflammatory and various other inflammatory neurologic diseases. This upregulation was confirmed by ELISA, showing increased BLC levels in every neuroborreliosis patient while being undetectable in patients with noninflammatory neurologic diseases. These results point to BLC as a putative additional diagnostic marker for neuroborreliosis.
The present study assessed the role of PARP poly(adenosine diphosphate-ribose) polymerase activation in experimental pneumococcal meningitis. Mice with a targeted disruption of the PARP1 gene were ...protected against meningitis-associated central nervous system complications including blood-brain barrier breaching and increase in intracranial pressure. This beneficial effect was paralleled by a significant reduction in meningeal inflammation, as evidenced by significantly lower cerebrospinal fluid leukocyte counts and interleukin-1β, −6, and tumor necrosis factor-α concentrations in the brain (compared with infected wild-type mice). The reduction in inflammation and central nervous system complications was associated with an improved clinical status of infected, PARP1-deficient mice. A similar protective effect was achieved by PARP inhibition using 3-aminobenzamide, the pharmacologic efficacy of which was confirmed by a marked attenuation of meningitis-induced poly(ADP)ribose formation. When the rat brain-derived endothelial cell line GP8.3 was cocultured with macrophages, exposure to pneumococci induced endothelial cell death and was paralleled by PARP activation and a reduction in the oxidized form of cellular nicotinamide adenine dinucleotide content. Treatment with 3-aminobenzamide significantly attenuated cellular nicotinamide adenine dinucleotide depletion and pneumococci-induced cytotoxicity. Thus, PARP activation seems to play a crucial role in the development of meningitis-associated central nervous system complications and pneumococci-induced endothelial injury. Inhibitors of PARP activation could provide a potential therapy of acute bacterial meningitis.
There is substantial evidence, implicating extracellular matrix (ECM) regulating enzymes in the pathogenesis of motor neuron degeneration in amyotrophic lateral sclerosis (ALS). The most important ...ECM-degrading proteases are serine proteases (plasminogen activators, PA) and matrix metalloproteinases (MMPs). Since the role of MMPs in ALS has been addressed recently, we investigated the expression of the serine protease urokinase-type plasminogen activator (uPA) and its receptor in ALS.
Employing rtPCR, zymography and immunohistochemistry we analyzed the expression of uPA and its receptor uPAR in spinal cord tissue of ALS cases and in the G93A SOD1 transgenic mouse. In the ventral horn of the spinal cord of ALS cases we found increased uPAR staining of motor neurons. In G93A mice, the expression profile of uPA and uPAR mRNA was significantly increased starting at the age of 90 days as compared to non-transgenic littermates. The uPA-dependent plasminogen activation in G93A mice at endstage increased markedly compared with controls and immunostaining of the spinal cord from G93A mice revealed increased uPAR immunostaining in neurons. To determine the functional role of uPA, we investigated the effect of intraperitoneal (i.p.) administration of the uPA inhibitor WX-340 (10 mg/kg), starting at the age of 30 days (
n
=
18). Treatment with WX-340 prolonged (
p
<
0.05) survival of the animals (135
±
2 vs. 126
±
3) as well as improving rotarod performance.
Our experiments demonstrate that uPA and its receptor are expressed in ALS patients and in an animal model of ALS. Early inhibition with a synthetic uPA inhibitor prolonged the life of the transgenic animals. These findings indicate that the urokinase-type plasminogen activator system may play a role in the complex pathogenesis of ALS.
The definitive diagnosis of acute neuroborreliosis (NB) is based upon the presence of lymphomonocytic CSF pleocytosis and intrathecal Borrelia burgdorferi (B.b.)-specific antibody production ...(expressed by an antibody index of >2). However, the latter might be absent in early stages of the disease. Now a recently discovered additional CSF marker-the cytokine CXCL13-was found to be positive in every initial CSF sample from patients with NB and therefore could be a valuable tool for early diagnosis and initiation of antibiotic therapy. We report an unusual case of NB in a patient with a history of metastatic carcinoma of the prostate and unilateral polyradiculitis. While no intrathecal B.b.-specific antibody production could be demonstrated initially, the CSF CXCL13 level was high (>500 ng/g vs <1.7 ng/g in healthy controls). During the course of the disease, the antibody index turned positive (4.8) and the patient responded to antibiotic therapy, thus confirming the diagnosis. In this case, measuring CXCL13 in the CSF would have led to earlier diagnosis and treatment of NB.
Extrusion of inorganic glass melts is demonstrated as a helpful approach for making fibreoptic preforms. Thus rods, and fine bore tubes, of good dimensional control and surface finish have been made ...of sodium borosilicate glasses and gallium lanthanum sulphide glasses. Problems of material compatibility and design of the extruder die have been addressed. One-step extrusion of core/clad preforms is also demonstrated, and optimisation of the extruder die design described to minimise taper of the core/clad ratio within the constant outside diameter preform.
Heterologous expression of Toll-like receptor (TLR)2 and CD14 in Chinese hamster ovary fibroblasts was reported to confer responsiveness to pneumococcal peptidoglycan. The present study characterized ...the role of TLR2 in the host immune response and clinical course of pneumococcal meningitis. Pneumococcal infection of mice caused a significant increase in brain TLR2 mRNA expression at both 4 and 24 h postchallenge. Mice with a targeted disruption of the TLR2 gene (TLR2-/-) showed a moderate increase in disease severity, as evidenced by an aggravation of meningitis-induced intracranial complications, a more pronounced reduction in body weight and temperature, and a deterioration of motor impairment. These symptoms were associated with significantly higher cerebellar and blood bacterial titers. Brain expression of the complement inhibitor complement receptor-related protein y was significantly higher in infected TLR2-/- than in wild-type mice, while the expression of the meningitis-relevant inflammatory mediators IL-1beta, TNF-alpha, IL-6, macrophage-inflammatory protein (MIP)-2, inducible NO synthase, and C3 was similar in both genotypes. We first ectopically expressed single candidate receptors in HEK293 cells and then applied peritoneal macrophages from mice lacking TLR2 and/or functional TLR4 for further analysis. Overexpression of TLR2 and TLR4/MD-2 conferred activation of NF-kappaB in response to pneumococcal exposure. However, pneumococci-induced TNF-alpha release from peritoneal macrophages of wild-type and TLR2/functional TLR4/double-deficient mice did not differ. Thus, while TLR2 plays a significant role in vivo, yet undefined pattern recognition receptors contribute to the recognition of and initiation of the host immune defense toward Streptococcus pneumoniae infection.
Myeloid differentiation factor 88 (MyD88) is an essential intracellular signal transducer in Toll‐like receptor (TLR) and interleukin (IL)‐1 receptor family member‐mediated cell activation. In order ...to characterize the role of MyD88 in pneumococcal meningitis we used gene‐targeted mice lacking functional MyD88 expression. At 24 h after intracisternal infection, MyD88‐ deficient mice displayed a markedly diminished inflammatory host response in the CNS, as evidenced by reduced CSF pleocytosis and expression of cytokines, chemokines and complement factors. The reduced CNS inflammation was paralleled by a marked reduction in the prognostic relevant CNS complications, such as brain oedema formation. Nevertheless, MyD88 deficiency was associated with a worsening of disease which seemed to be attributable to severe bacteraemia. This notion was supported by the unexpected observation that infected MyD88‐deficient mice displayed enhanced mRNA expression of inflammatory mediators such as the proinflammatory cytokine tumour necrosis factor α (TNF‐α) and the CXC chemokine macrophage inflammatory protein (MIP‐2) in the lung and consequently increased cell influx in the bronchoalveolar lavage fluid, compared with infected wild‐type mice. Thus, the present study demonstrated for the first time an important role of MyD88 in immune activation to bacterial pathogens within the CNS. The role played by MyD88 in mounting an immune response to Streptococcus pneumoniae, however, seems to be dependent on the anatomical compartment involved.
Endogenous molecules released from disrupted cells and extracellular matrix degradation products activate Toll-like receptors (TLRs) and, thus, might contribute to immune activation after tissue ...injury. Here, we show that aseptic, cold-induced cortical injury triggered an acute immune response that involves increased production of multiple cytokines/chemokines accompanied by neutrophil recruitment to the lesion site. We observed selective reductions in injury-induced cytokine/chemokine expression as well as in neutrophil accumulation in mice lacking the common TLR signaling adaptor MyD88 compared with wild-type mice. Notably, attenuation of the immune response was paralleled by a reduction in lesion size. Neutrophil depletion of wild-type mice and transplantation of MyD88-deficient bone marrow into lethally irradiated wild-type recipients had no substantial impact on injury-induced expression of cytokines/chemokines and on lesion development. In contrast to MyD88 deficiency, double deficiency of TLR2 and TLR4—despite the two receptors being activated by specific endogenous molecules associated to danger and signal through MyD88—altered neither immune response nor extent of tissue lesion size on injury. Our data indicate modulation of the neuroinflammatory response and lesion development after aseptic cortical injury through MyD88-dependent but TLR2/4-independent signaling by central nervous system resident nonmyeloid cells.
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