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Recent studies have suggested the potential of innovative serologic tests for accurate and rapid detection of bovine tuberculosis (bTB). Dual Path Platform (DPP) technology has been used to develop rapid animal-side antibody tests for Mycobacterium bovis infection in a range of livestock and wildlife host species. The present study evaluated diagnostic performance of DPP BovidTB IgM/IgG assay designed for differential detection of bovine IgM and IgG antibodies against two chimeric antigens, DID38 and TBf2, respectively, using 662 well-characterized serum samples from M. bovis-infected and bTB-free cattle collected in the United States, Great Britain, France, and South Africa. Test sensitivity and specificity ranged from 71% to 100% and from 95% to 100%, respectively, depending on the country, with overall accuracy of 83%. No significant risk of cross-reactivity with serum samples from cattle infected with most relevant species of mycobacteria other than M. bovis was found. The DPP BovidTB IgM/IgG assay may be suitable for use in multi-test algorithms to improve current strategies for bTB surveillance.

The present study highlights the transboundary nature of tuberculosis (TB) in alpacas and the failure of current antemortem testing protocols to identify TB-free alpaca herds and individuals for exportation. The tuberculin skin test (TST) failed to identify Mycobacterium bovis-infected animals prior to movement from the United Kingdom (UK) to Poland. This study describes the use of four serological assays [Enferplex Camelid TB, dual-path platform (DPP) VetTB and BovidTB assays, and multi-antigen print immunoassays (MAPIAs)] to detect TB in an alpaca herd with negative TST results. The breeding in Poland purchased alpacas for several years from the UK with the last group arriving in May 2018. In July 2018, two sick alpacas from the centre were hospitalized in a veterinary clinic and both died of TB a few weeks later. In November 2018, 20 alpacas remaining in this M. bovis-affected herd were euthanized and samples were collected. The study population included 20 M. bovis-infected and 20 uninfected alpacas, but only 15 infected animals were tested by all serology tests. The DPP VetTB and DPP BovidTB assays detected antibodies in 14 of the 20 infected alpacas, with results confirmed by MAPIA, and in none (MAPIA and DPP BovidTB) or one (DPP VetTB) of the 20 uninfected animals. None of the infected alpacas tested positive using the Enferplex assay. In addition, the group included three orphans and two cria-dam pairs, which provided an opportunity to analyse immune aspects of cria-mother relationships in this herd. The results suggest high susceptibility of this host species to M. bovis infection and rapid progression to disease. The serological tests used in this study offer useful tools for the detection of M. bovis infection in TST and Enferplex test non-reactive alpacas. These tests should be further evaluated for implementation into TB management and control strategies for camelid species.

Bovine tuberculosis (bTB) control programs can be improved by combined use of tests for humoral and cell-mediated immune responses targeting multiple biomarkers of Mycobacterium bovis. To further the diagnostic benefits of this approach, we used Dual Path Platform (DPP) technology to test sera from cattle with naturally acquired bTB in the United States (US) and Spain for the presence of M. bovis antigen, IgM and/or IgG antibodies to MPB70/MPB83 fusion antigen in conjunction with tuberculin skin tests (TST) or interferon-gamma release assays (IGRA). When TST was complemented with detection of IgM and IgG antibodies, the diagnostic sensitivity increased from 85.4% to 95.1% in the US and from 64.2% to 81.5% in Spain. Likewise, adding the DPP assays enhanced IGRA diagnostic sensitivity from 82.7% to 93.8% in Spain. Detection of circulating M. bovis antigen showed added value when used in combination with the DPP antibody assays but it was limited when analyzed in the context of TST or IGRA results. Present findings support the benefits of a multi-test approach for the ante-mortem diagnosis of bTB in cattle., This work was supported by the Small Business Innovation Research Program of the USDA National Institute of Food and Agriculture (Award No. 2016-33610-25688).

Bovine tuberculosis (bTB) control programs can be improved by implementation of advanced ante-mortem testing algorithms. Serodiagnostic methods using traditional blood or blood-derived specimens may benefit from the use of less invasive alternative biological fluids, provided those mirror systemic antibody responses. In the present study, we used Dual Path Platform (DPP) and Multiantigen Print Immunoassay (MAPIA) to compare antibody levels in ten sample types including whole blood (fresh and hemolyzed), plasma (fresh and leftover from Bovigam testing), serum, saliva, broncho-alveolar lavage, urine, diaphragm extract, and bile collected from cattle aerosol-infected with Mycobacterium bovis. High correlation (r = 0.97-0.99) in measurements of IgG antibodies to MPB70/MPB83 fusion antigen by DPP assay was found between all blood-derived specimens, supporting matrix equivalency. Broncho-alveolar lavage and diaphragm extract yielded positive results in all the infected animals tested, showing high correlation with matching serum data (r = 0.94 and r = 0.95, respectively) and suggesting their potential use in antibody assays. Characterized by MAPIA, the antigen reactivity patterns obtained with paired sera and alternative specimens were nearly identical, with slight differences in intensity. Antibodies were also found by DPP assay in saliva, urine, and bile from some of the infected animals, but the titers were relatively low, thus reducing the diagnostic value of such specimens. The proposed approach was evaluated in a pilot field study on warthogs diagnosed with M. bovis infection. Relative levels of antibody in tissue fluid obtained from lymph nodes or lungs were consistent with those detected in sera and detectable in all infected warthogs. The findings support the diagnostic utility of non-traditional biological fluids and tissue samples when used as alternative test specimens in serologic assays for bTB.

Mycobacterium caprae, a member of the Mycobacterium tuberculosis complex, infects humans and animals causing lesions and disease like that of Mycobacterium bovis. The aim of this study was to evaluate antibody responses in European Bison (EB, Bison bonasus; a vulnerable species) naturally infected with M. caprae using dual path platform (DPP) BovidTB test and multi-antigen print immunoassay (MAPIA). Study cohorts consisted of naturally M. caprae-infected EB (n = 4), M. caprae-exposed but uninfected (n = 3), EB infected with non-tuberculous mycobacteria or other respiratory pathogens (n = 3), and negative controls (n = 19). M. caprae-infected EB were seropositive by both DPP and MAPIA; 3/4 were seropositive by DPP; and 4/4 were seropositive by MAPIA. One M. caprae-infected animal that developed generalized disease with most advanced gross lesions in the group produced the most robust antibody response. All 25 EB with no culture-confirmed M. caprae infection, including three animals exposed to M. caprae and three other animals infected with non-tuberculous pathogens, were seronegative on both tests. Antibody responses to M. caprae infection included IgM antibodies against MPB70/MPB83 and IgG antibodies to both MPB70/MPB83 and CFP10/ESAT-6. This study demonstrates the potential for use of serological assays in the ante-mortem diagnosis of M. caprae infection in EB.

Recent studies have demonstrated potential for serologic assays to improve surveillance and control programs for bovine tuberculosis. Due to the animal-to-animal variation of the individual antibody repertoires observed in bovine tuberculosis, it has been suggested that serodiagnostic sensitivity can be maximized by use of multi-antigen cocktails or genetically engineered polyproteins expressing immunodominant B-cell epitopes. In the present study, we designed three novel multiepitope polyproteins named BID109, TB1f, and TB2f, with each construct representing a unique combination of four full-length peptides of Mycobacterium bovis predominantly recognized in bovine tuberculosis. Functional performance of the fusion antigens was evaluated using multi-antigen print immunoassay (MAPIA) and Dual Path Platform (DPP) technology with panels of monoclonal and polyclonal antibodies generated against individual proteins included in the fusion constructs as well as with serum samples from M. bovis-infected and non-infected cattle, American bison, and domestic pigs. It was shown that epitopes of each individual protein were expressed in the fusion antigens and accessible for efficient binding by the respective antibodies. The three fusion antigens demonstrated stronger immunoreactivity in MAPIA than that of single protein antigens. Evaluation of the fusion antigens in DPP assay using serum samples from 125 M. bovis-infected and 57 non-infected cattle showed the best accuracy (∼84 %) for TB2f antigen composed of MPB70, MPB83, CFP10, and Rv2650c proteins. Thus, the study results suggest a potential for the multiepitope polyproteins to improve diagnostic sensitivity of serologic assays for bovine tuberculosis.

Domestic pigs and wild suids are susceptible to Mycobacterium bovis (M. bovis) infection and may even serve as reservoir hosts in some situations. Therefore, detection of infected animals is important for understanding their role in the epidemiology of the disease as well as for management and control of bovine tuberculosis. Infected suids develop strong humoral responses, making serological screening a feasible approach to disease surveillance. However, to optimize sensitivity of the antibody assays, it is necessary to identify and incorporate immunodominant antigens recognized by the target species. The objective of this study was to characterize the antigen recognition by three suid species in a commercially available serological test, DPP VetTB Assay. Serum samples from naturally M. bovis-infected domestic pigs, wild boar and common warthogs were tested. MPB83 protein appeared to be the immunodominant antigen recognized by antibodies in all three species. Overall test sensitivity was increased in wild suids when seroreactivity to CFP10/ESAT-6 antigen was included. Infected animals with visible lesions showed more robust antibody responses than those without gross lesions. The high sensitivity and specificity of the DPP VetTB Assay demonstrated in the present study supports the utility of antibody tests employing these antigens in serological screening of the suid species for M. bovis infection., Financial support (MAM, EOR) was provided by the South African Medical Research Council, NRF South African Research Chair Initiative (SARChI, grant 86949) and the American Association of Zoological Medicine Wild Animal Health Fund (#7-2016).

Supersymmetry is a promising framework in which to explore extensions of the standard model. If candidates for supersymmetric particles are found, precision measurements of their properties will then be of paramount importance. The prospects for such measurements and their implications are the subject of this thesis. If charginos are produced at the LEP II collider, they are likely to be one of the few available supersymmetric signals for many years. The author considers the possibility of determining fundamental supersymmetry parameters in such a scenario. The study is complicated by the dependence of observables on a large number of these parameters. He proposes a straightforward procedure for disentangling these dependences and demonstrate its effectiveness by presenting a number of case studies at representative points in parameter space. In addition to determining the properties of supersymmetric particles, precision measurements may also be used to establish that newly-discovered particles are, in fact, supersymmetric. Supersymmetry predicts quantitative relations among the couplings and masses of superparticles. The author discusses tests of such relations at a future e{sup +}e{sup {minus}} linear collider, using measurements that exploit the availability of polarizable beams. Stringent tests of supersymmetry from chargino production are demonstrated in two representative cases, and fermion and neutralino processes are also discussed.

125 Background: GLS-010 is a novel fully human anti-PD-1 mAb. Phase Ia exhibited good result of tolerance and 240mg fixed dose was selected. Phase Ib is to explore efficacy and biomarkers in different types of advanced cancer. Here we report the preliminary result in Chinese gastrointestinal (GI) tumor patients (pts) from the phase Ib. Methods: All pts enrolled received GLS-010 240mg every 2 weeks. Tumor response was assessed by RECIST 1.1 every 8 weeks. Adverse events (AEs) were graded by NCI CTCAE v4.03. Several biomarkers were evaluated, including PD-L1 by IHC, tissue tumor mutation burden (tTMB) by whole exome sequencing (WES) from FFPE tissue, blood TMB (bTMB) by the multi-gene panel based next-generation sequencing (NGS) from blood ctDNA. Results: Until September 2018, 23 pts (including 10 gastric cancer or GC, 10 esophagus cancer or EC, and 3 biliary tract cancer or BTC) were enrolled in the phase 1b. The median dosing number was 4 (range: 1~16). The most common treatment related AEs included haemoglobin decreased (16/23, G1-2), leukopenia (6/23, G1-2), fever (4/23, G1), blood bilirubin increased (4/23, G1-3), ALT increased (3/23, G1), etc. Treatment–related grade 3-5 AEs include 1 multiple organ dysfunction syndrome, 1 interstitial lung disease and 1 blood bilirubin increased. 21 pts received response evaluation. Four patients achieved partial response (PR), including 1 GC (1/9), 2 EC (2/10), and 1 BTC (1/2). 2 subjects had stable disease (SD) at Week 8, and were still in treatment. No apparent correlation was observed between treatment response and PD-L1 expression. However, both tTMB and bTMB data obtained from 18 patients support positive correlation to tumor response. The tTMB level of 3 PR pts with valid data is significantly higher than that of 9 PD pts (P = 0.036). The bTMB level of 4 PR pts with valid data is significantly higher than that of 10 PD pts (P = 0.049). Conclusions: GLS-010 showed promising efficacy and acceptable safety in Chinese patients. For Chinese GI tumor TMB may be a useful biomarker to predict the treatment response to PD-1 inhibitor. Comparing to tTMB, bTMB may be of more future value due to its applicability in clinical practice.

Ebolavirus Reston was detected in samples taken from pigs on two farms in the northern Philippines in mid-2008. This was the first known case of any of the filoviruses being detected in pigs anywhere in the world. Previously, filoviruses have only been isolated from humans and non-human primates, although serological evidence indicates that bats may also be infected with these viruses. Serological evidence of infection was also detected in six of 147 in-contact people tested as part of the investigation into this outbreak.

The tensile behavior of bimodal nanocrystalline Al-7.5Mg alloys was investigated using experiments and two-dimensional axisymmetric elastic-plastic finite element method (FEM). Cryomilled nanocrystalline powders blended with 15% and 30% unmilled coarse-grained powders were consolidated by hot isostatic pressing followed by extrusion to produce bulk bimodal nanocrystalline Al-7.5Mg alloys, which were comprised of nanocrystalline grains separated by coarse-grain regions. The calculated stress-strain curves have acceptable agreement with experimental curves of the bimodal structures. The bimodal Al-7.5Mg alloys show reasonable ductility while retaining enhanced strength compared to conventional alloys and nanocrystalline metals.