Immunology of BCG vaccination in mice : implications for tuberculosis vaccination and for the use of BCG as a recombinant vaccine vector

The effect of vaccination dose on the immune response of mice to Mycobacterium bovis Bacille Calmette-Guerin (BCG) was examined. To assess T helper cell-type 1 (Th1) and -type 2 (Th2) responses, a very sensitive ELISPOT assay was developed. Using this assay, the numbers of BCG-specific interferon ɣ- and interleukin 4-producing spleen cells were used as indicators of the Th1 and Th2 responses, respectively. IgG1 and IgG2a serum antibody titers were also assessed. Mice were immunized with different doses of BCG, and their immune response to BCG antigen was determined at various times after vaccination. Low dose immunized mice developed predominantly Th1 responses and little antibody, while those given higher numbers of bacilli generated a mixed Th1/Th2 response and had significant antibody titers. Furthermore, mice given the lower doses of BCG developed an immune imprint that enabled them to resist development of a Th2 response on subsequent challenge with a higher dose of BCG, which generates a Th2 response in previously unexposed mice. The immune response of mice immunized with recombinant BCG (rBCG) expressing 'Escherichia coli' β-galactosidase was also characterized. Th1 cells predominated in the immune response to BCG antigen as well as to the expressed β-galactosidase antigen in low dose vaccinated mice. Moreover, the Th1 response to both antigens was stable after high dose challenge of low dose vaccinated animals indicating that immune imprinting had been established both to BCG and to the recombinant β-galactosidase antigen. The results indicate that the immune state that develops in mice upon vaccination with BCG depends on the initial dose of antigen administered, with low amounts of antigen leading to Th1 immunity, and relatively high amounts of antigen leading to Th2 immune responses. 'Mycobacterium tuberculosis ' is only controlled effectively by a cell-mediated immune response. Immunization with a relatively low dose of BCG, rather than the current standard dose, may provide greater immune protection against 'M. tuberculosis'. Moreover, low dose vaccination with rBCG expressing proteins of leishmania or HIV promises to be an effective means of vaccination against diseases caused by these pathogens, which can only be contained by a Th1 response

Development of Th1 Imprints to rBCG Expressing a Foreign Protein: Implications for Vaccination against HIV-1 and Diverse Influenza Strains

We demonstrate here that immunizing naïve mice with low numbers of recombinant Bacille Calmette-Guérin (rBCG) expressing β-galactosidase (β-gal) generates predominant Th1 responses to both BCG and β-gal whereas infection with high numbers generates a mixed Th1/Th2 response to both BCG and β-gal. Furthermore, the Th1 response to both BCG and β-gal is stable when mice, pre-exposed to low numbers of rBCG, are challenged four months later with high numbers of rBCG. Thus the Th1/Th2 phenotypes of the immune responses to β-gal and to BCG are “coherently” regulated. Such rBCG vectors, encoding antigens of pathogens preferentially susceptible to cell-mediated attack, may be useful in vaccinating against such pathogens. We discuss vaccination strategies employing rBCG vectors that are designed to provide protection against diverse influenza strains or numerous variants of HIV-1 and consider what further experiments are essential to explore the possibility of realizing such strategies

A low-voltage CMOS multiplier for RF applications

This work is part of a project funded under the Fourth Italian-Maltese Financial Protocol.A low-voltage analog multiplier operating at 1.2 V is presented. The multiplier core consists of four MOS transistors operating in the saturation region. The circuit exploits the quadratic relation between current and voltage of the MOS transistor in saturation. The circuit was designed using standard 0.6 /spl mu/m CMOS technology. Simulation results indicate an IP3 of 4.9 dBm and a spur free dynamic range of 45 dB.peer-reviewe

Microscopic diffusion properties of fixed breast tissue: Preliminary findings

Purpose: To investigate the microscopic diffusion properties of formalin-fixed breast tissue

Incidence and outcome of in-hospital cardiac arrest in the United Kingdom National Cardiac Arrest Audit

Objective To report the incidence, characteristics and outcome of adult in-hospital cardiac arrest in the United Kingdom (UK) National Cardiac Arrest Audit database. Methods A prospectively defined analysis of the UK National Cardiac Arrest Audit (NCAA) database. 144 acute hospitals contributed data relating to 22,628 patients aged 16 years or over receiving chest compressions and/or defibrillation and attended by a hospital-based resuscitation team in response to a 2222 call. The main outcome measures were incidence of adult in-hospital cardiac arrest and survival to hospital discharge. Results The overall incidence of adult in-hospital cardiac arrest was 1.6 per 1000 hospital admissions with a median across hospitals of 1.5 (interquartile range 1.2–2.2). Incidence varied seasonally, peaking in winter. Overall unadjusted survival to hospital discharge was 18.4%. The presenting rhythm was shockable (ventricular fibrillation or pulseless ventricular tachycardia) in 16.9% and non-shockable (asystole or pulseless electrical activity) in 72.3%; rates of survival to hospital discharge associated with these rhythms were 49.0% and 10.5%, respectively, but varied substantially across hospitals. Conclusions These first results from the NCAA database describing the current incidence and outcome of adult in-hospital cardiac arrest in UK hospitals will serve as a benchmark from which to assess the future impact of changes in service delivery, organisation and treatment for in-hospital cardiac arrest

Development of Th1 Imprints to rBCG Expressing a Foreign Protein: Implications for Vaccination against HIV-1 and Diverse Influenza Strains

We demonstrate here that immunizing naïve mice with low numbers of recombinant Bacille Calmette-Guérin (rBCG) expressing β-galactosidase (β-gal) generates predominant Th1 responses to both BCG and β-gal whereas infection with high numbers generates a mixed Th1/Th2 response to both BCG and β-gal. Furthermore, the Th1 response to both BCG and β-gal is stable when mice, pre-exposed to low numbers of rBCG, are challenged four months later with high numbers of rBCG. Thus the Th1/Th2 phenotypes of the immune responses to β-gal and to BCG are "coherently" regulated. Such rBCG vectors, encoding antigens of pathogens preferentially susceptible to cell-mediated attack, may be useful in vaccinating against such pathogens. We discuss vaccination strategies employing rBCG vectors that are designed to provide protection against diverse influenza strains or numerous variants of HIV-1 and consider what further experiments are essential to explore the possibility of realizing such strategies

Zoledronic Acid Preserves Bone Structure and Increases Survival but Does Not Limit Tumour Incidence in a Prostate Cancer Bone Metastasis Model

Background The bisphosphonate, zoledronic acid (ZOL), can inhibit osteoclasts leading to decreased osteoclastogenesis and osteoclast activity in bone. Here, we used a mixed osteolytic/osteoblastic murine model of bone-metastatic prostate cancer, RM1(BM), to determine how inhibiting osteolysis with ZOL affects the ability of these cells to establish metastases in bone, the integrity of the tumour-bearing bones and the survival of the tumour-bearing mice. Methods The model involves intracardiac injection for arterial dissemination of the RM1(BM) cells in C57BL/6 mice. ZOL treatment was given via subcutaneous injections on days 0, 4, 8 and 12, at 20 and 100 µg/kg doses. Bone integrity was assessed by micro-computed tomography and histology with comparison to untreated mice. The osteoclast and osteoblast activity was determined by measuring serum tartrate-resistant acid phosphatase 5b (TRAP 5b) and osteocalcin, respectively. Mice were euthanased according to predetermined criteria and survival was assessed using Kaplan Meier plots. Findings Micro-CT and histological analysis showed that treatment of mice with ZOL from the day of intracardiac injection of RM1(BM) cells inhibited tumour-induced bone lysis, maintained bone volume and reduced the calcification of tumour-induced endochondral osteoid material. ZOL treatment also led to a decreased serum osteocalcin and TRAP 5b levels. Additionally, treated mice showed increased survival compared to vehicle treated controls. However, ZOL treatment did not inhibit the cells ability to metastasise to bone as the number of bone-metastases was similar in both treated and untreated mice. Conclusions ZOL treatment provided significant benefits for maintaining the integrity of tumour-bearing bones and increased the survival of tumour bearing mice, though it did not prevent establishment of bone-metastases in this model. From the mechanistic view, these observations confirm that tumour-induced bone lysis is not a requirement for establishment of these bone tumours

The Making of the NEAM Tsunami Hazard Model 2018 (NEAMTHM18)

The NEAM Tsunami Hazard Model 2018 (NEAMTHM18) is a probabilistic hazard model for tsunamis generated by earthquakes. It covers the coastlines of the North-eastern Atlantic, the Mediterranean, and connected seas (NEAM). NEAMTHM18 was designed as a three-phase project. The first two phases were dedicated to the model development and hazard calculations, following a formalized decision-making process based on a multiple-expert protocol. The third phase was dedicated to documentation and dissemination. The hazard assessment workflow was structured in Steps and Levels. There are four Steps: Step-1) probabilistic earthquake model; Step-2) tsunami generation and modeling in deep water; Step-3) shoaling and inundation; Step-4) hazard aggregation and uncertainty quantification. Each Step includes a different number of Levels. Level-0 always describes the input data; the other Levels describe the intermediate results needed to proceed from one Step to another. Alternative datasets and models were considered in the implementation. The epistemic hazard uncertainty was quantified through an ensemble modeling technique accounting for alternative models’ weights and yielding a distribution of hazard curves represented by the mean and various percentiles. Hazard curves were calculated at 2,343 Points of Interest (POI) distributed at an average spacing of ∼20 km. Precalculated probability maps for five maximum inundation heights (MIH) and hazard intensity maps for five average return periods (ARP) were produced from hazard curves. In the entire NEAM Region, MIHs of several meters are rare but not impossible. Considering a 2% probability of exceedance in 50 years (ARP≈2,475 years), the POIs with MIH >5 m are fewer than 1% and are all in the Mediterranean on Libya, Egypt, Cyprus, and Greece coasts. In the North-East Atlantic, POIs with MIH >3 m are on the coasts of Mauritania and Gulf of Cadiz. Overall, 30% of the POIs have MIH >1 m. NEAMTHM18 results and documentation are available through the TSUMAPS-NEAM project website (http://www.tsumaps-neam.eu/), featuring an interactive web mapper. Although the NEAMTHM18 cannot substitute in-depth analyses at local scales, it represents the first action to start local and more detailed hazard and risk assessments and contributes to designing evacuation maps for tsunami early warning.publishedVersio

The Making of the NEAM Tsunami Hazard Model 2018 (NEAMTHM18)

ABSTRACT: The NEAM Tsunami Hazard Model 2018 (NEAMTHM18) is a probabilistic hazard model for tsunamis generated by earthquakes. It covers the coastlines of the North-eastern Atlantic, the Mediterranean, and connected seas (NEAM). NEAMTHM18 was designed as a three-phase project. The first two phases were dedicated to the model development and hazard calculations, following a formalized decision-making process based on a multiple-expert protocol. The third phase was dedicated to documentation and dissemination. The hazard assessment workflow was structured in Steps and Levels. There are four Steps: Step-1) probabilistic earthquake model; Step-2) tsunami generation and modeling in deep water; Step-3) shoaling and inundation; Step-4) hazard aggregation and uncertainty quantification. Each Step includes a different number of Levels. Level-0 always describes the input data; the other Levels describe the intermediate results needed to proceed from one Step to another. Alternative datasets and models were considered in the implementation. The epistemic hazard uncertainty was quantified through an ensemble modeling technique accounting for alternative models' weights and yielding a distribution of hazard curves represented by the mean and various percentiles. Hazard curves were calculated at 2,343 Points of Interest (POI) distributed at an average spacing of ∼20 km. Precalculated probability maps for five maximum inundation heights (MIH) and hazard intensity maps for five average return periods (ARP) were produced from hazard curves. In the entire NEAM Region, MIHs of several meters are rare but not impossible. Considering a 2% probability of exceedance in 50 years (ARP≈2,475 years), the POIs with MIH >5 m are fewer than 1% and are all in the Mediterranean on Libya, Egypt, Cyprus, and Greece coasts. In the North-East Atlantic, POIs with MIH >3 m are on the coasts of Mauritania and Gulf of Cadiz. Overall, 30% of the POIs have MIH >1 m. NEAMTHM18 results and documentation are available through the TSUMAPS-NEAM project website (http://www.tsumaps-neam.eu/), featuring an interactive web mapper. Although the NEAMTHM18 cannot substitute in-depth analyses at local scales, it represents the first action to start local and more detailed hazard and risk assessments and contributes to designing evacuation maps for tsunami early warning

Erratum to: Methods for evaluating medical tests and biomarkers

[This corrects the article DOI: 10.1186/s41512-016-0001-y.]