Defining novel functions for cerebrospinal fluid in ALS pathophysiology

Despite the considerable progress made towards understanding ALS pathophysiology, several key features of ALS remain unexplained, from its aetiology to its epidemiological aspects. The glymphatic system, which has recently been recognised as a major clearance pathway for the brain, has received considerable attention in several neurological conditions, particularly Alzheimer's disease. Its significance in ALS has, however, been little addressed. This perspective article therefore aims to assess the possibility of CSF contribution in ALS by considering various lines of evidence, including the abnormal composition of ALS-CSF, its toxicity and the evidence for impaired CSF dynamics in ALS patients. We also describe a potential role for CSF circulation in determining disease spread as well as the importance of CSF dynamics in ALS neurotherapeutics. We propose that a CSF model could potentially offer additional avenues to explore currently unexplained features of ALS, ultimately leading to new treatment options for people with ALS.</p

Evaluating aerosol administration of a candidate TB vaccine, MVA85A, as a way to induce potent local cellular immune responses and avoid anti-vector immunity

There is an urgent need for a better vaccine against TB than BCG, which confers variable protection against pulmonary TB. Heterologous prime-boost regimens with viral vector vaccines are a leading strategy for TB vaccine development. MVA85A is a viral vector candidate TB vaccine designed to boost BCG. This phase I clinical trial was designed to evaluate whether alternating aerosol and intradermal routes of vaccination can improve Ag85A immunogenicity; maybe by circumventing local anti- MVA immunity. Thirty-six BCG-vaccinated healthy UK adults received two MVA85A vaccinations one month apart as heterologous (aerosol-intradermal or intradermalaerosol) or homologous prime-boost (intradermal-intradermal). Bronchoscopies with bronchoalveolar lavages (BAL) were performed 7 days after each vaccination. Delivering MVA85A by aerosol as a priming immunisation was well tolerated and highly immunogenic. Boosting an intradermal MVA85A prime with an aerosolised MVA85A vaccination led to transient respiratory and systemic adverse events which resulted in vaccinations in this group ceasing. Aerosolised MVA85A induced potent Ag85A-specific T cell responses in mucosal and systemic compartments; and suggested a potential for dose sparing with this route. The intradermal-aerosol regimen boosted Ag85A-specific cellular immune responses in systemic and lung mucosal compartments. Serum antibodies to Ag85A and MVA were only detected after intradermal vaccination. Anti-Ag85A antibodies in serum were boosted by a second intradermal vaccination. The findings of this trial are important for the development of aerosolised TB vaccines but also for new viral vector vaccines for other respiratory pathogens.</p

Optimization of a human bacille Calmette-Guerin challenge model: a tool to evaluate antimycobacterial immunity

There is an urgent need for an improved tuberculosis vaccine. The lack of a validated correlate of protection slows progress in achieving this goal. A human mycobacterial challenge model, using bacille Calmette-Guérin (BCG) as a surrogate for a Mycobacterium tuberculosis challenge, would facilitate vaccine selection for field efficacy testing. Optimization of this model is required.Healthy BCG-naive adults were assigned to receive intradermal standard-dose BCG SSI (group A), standard-dose BCG TICE (group B), high-dose BCG SSI (group C), and high-dose BCG TICE (group D). Two weeks after BCG challenge, skin biopsy of the challenge site was performed. BCG mycobacterial load was quantified by solid culture and quantitative polymerase chain reaction.BCG was well tolerated, and reactogenicity was similar between groups, regardless of strain and dose. There was significantly greater recovery of BCG from the high-dose challenge groups, compared with standard-dose challenge. BCG strain did not significantly affect BCG recovery.BCG challenge dose affects sensitivity of this model. We have selected high-dose BCG SSI to take forward in future challenge studies. Assessment of candidate tuberculosis vaccine effectiveness with this optimized model could contribute to vaccine selection for efficacy trials.NCT02088892

Optimisation of a human BCG challenge model

Tuberculosis remains a significant global disease burden with an estimated 9 million new cases and 1.5 million deaths in 2013. BCG continues to be the only licensed TB vaccine, however it is poorly efficacious against adult pulmonary TB disease and there is a desperate need for a better vaccine to provide greater and more consistent protection. Development of such a vaccine has been hampered by the lack of reliable and validated correlates of protection. A human mycobacterial challenge model, using BCG as a surrogate for Mycobacterium tuberculosis challenge would facilitate improved vaccine selection for progression into future field efficacy testing. In this study we evaluate the effect of two BCG strains at two doses to optimise this model

Inhibition of mycobacterial growth in vitro following primary but not secondary vaccination with Mycobacterium bovis BCG.

Despite the widespread use of the Mycobacterium bovis BCG vaccine, there are more than 9 million new cases of tuberculosis (TB) every year, and there is an urgent need for better TB vaccines. TB vaccine candidates are selected for evaluation based in part on the detection of an antigen-specific gamma interferon (IFN-γ) response. The measurement of mycobacterial growth in blood specimens obtained from subjects immunized with investigational TB vaccines may be a better in vitro correlate of in vivo vaccine efficacy. We performed a clinical study with 30 United Kingdom adults who were followed for 6 months to evaluate the abilities of both a whole-blood- and a novel peripheral blood mononuclear cell (PBMC)-based mycobacterial growth inhibition assay to measure a response to primary vaccination and revaccination with BCG. Using cryopreserved PBMCs, we observed a significant improvement in mycobacterial growth inhibition following primary vaccination but no improvement in growth inhibition following revaccination with BCG (P < 0.05). Mycobacterial growth inhibition following primary BCG vaccination was not correlated with purified protein derivative (PPD) antigen-specific IFN-γ enzyme-linked immunospot (ELISPOT) responses. We demonstrate that a mycobacterial growth inhibition assay can detect improved capacity to control growth following primary immunization, but not revaccination, with BCG. This is the first study to demonstrate that an in vitro growth inhibition assay can identify a difference in vaccine responses by comparing both primary and secondary BCG vaccinations, suggesting that in vitro growth inhibition assays may serve as better surrogates of clinical efficacy than the assays currently used for the assessment of candidate TB vaccines

The sex ratio in amyotrophic lateral sclerosis: A population based study.

Replicable risk factors for ALS include increasing age, family history and being male. The male: female ratio has been reported as being between 1 and 3. We tested the hypothesis that the sex ratio changes with age in a population register covering the south-east of England. The sex ratio before and after the age of 51 years was compared using a Z-test for proportions. Kendall's tau was used to assess the relationship between age group and sex ratio using incidence and prevalence data. Publicly available data from Italian and Irish population registers were compared with results. There was a significant difference in the proportion of females with ALS between those in the younger group (30.11%) and those in the older group (43.66%) (p = 0.013). The adjusted male: female ratio dropped from 2.5 in the younger group to 1.4 in the older group using prevalence data (Kendall's tau = -0.73, p = 0.039). Similar ratios were found in the Italian but not the Irish registry. We concluded that sex ratios in ALS may change with age. Over-representation of younger patients in clinic registers may explain the variation in sex ratios between studies. Menopause may also play a role

An efficient algorithm for optimization in nonlinear model predictive control of large-scale systems

Available from TIB Hannover: RR 1606(2002,11) / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekSIGLEDeutsche Forschungsgemeinschaft (DFG), Bonn (Germany)DEGerman