Characterisation of scFv A7 reactivity and development of a novel bispecific antibody for targeted therapies in Rheumatoid Arthritis.

PhDDespite the success of current biological agents, achievement of broader efficacy and improved safety profile remains an unmet need in rheumatoid arthritis therapy. Neovasculogenesis plays a vital role in the progression and perpetuation of rheumatoid arthritis and significant evidence has demonstrated molecular heterogeneity within the endothelium (MVE) of different tissues. The heterogeneity of the synovial MVE can be exploited for the development of organ-specific therapeutic and diagnostic reagents. A novel recombinant antibody fragment, scFv A7, with specificity for human arthritic synovium, was isolated in our laboratory following in vivo phage display. The aim of the project described in this thesis is to characterise the antibody reactivity and develop a novel tissue specific therapeutic. The scFv A7 antibody proved to specifically target the microvasculature of human arthritic synovium with no detectable reactivity in a comprehensive range of normal tissues. Furthermore, the detected reactivity was not a common feature of chronic inflammatory conditions. Hence, the A7 antibody represents a unique and versatile tool with great potential for the development of diagnostic and/or therapeutic agents. The unique properties of A7 were combined with the anti-TNF Adalimumab, forming a bispecific antibody with neutralising activity and synovial homing properties. The new construct was able to retain the synovial specificity and showed comparable TNF binding kinetics and biological activity to the parent Adalimumab antibody in vitro. In conclusion, these results demonstrate that scFv A7 reactivity is specific to the microvasculature of human arthritic synovium, suggesting that the target molecule may have potential as a biomarker in arthritis and applications as an immunotherapeutic target. The bispecific antibody format developed showed unaltered TNF blocking capacity and synovial specificity that may allow reduction in the dosage and/or administration frequency, with the ultimate goal to reduce the systemic exposure, achieve a better therapeutic index and decreasing health care costs

Profit Shifting Frictions and the Geography of Multinational Activity

We develop a quantitative general equilibrium model of multinational activity embedding corporate taxation and profit shifting. In addition to trade and investment frictions, our model shows that profit-shifting frictions shape the geography of multinational production. Key to our model is the distinction between the corporate tax elasticity of real activity and profit shifting. The quantification of our model requires estimates of shifted profits flows. We provide a new, model-consistent methodology to calibrate bilateral profit-shifting frictions based on accounting identities. We simulate various tax reforms aimed at curbing tax-dodging practices of multinationals and their impact on a range of outcomes, including tax revenues and production. Our results show that the effects of the international relocation of firms across countries are of comparable magnitude as the direct gains in taxable income

A new self-expanding aortic stent valve with annular fixation: in vitro haemodynamic assessment

Objective: Balloon-expandable stent valves require flow reduction during implantation (rapid pacing). The present study was designed to compare a self-expanding stent valve with annular fixation versus a balloon-expandable stent valve. Methods: Implantation of a new self-expanding stent valve with annular fixation (Symetis®, Lausanne, Switzerland) was assessed versus balloon-expandable stent valve, in a modified Dynatek Dalta® pulse duplicator (sealed port access to the ventricle for transapical route simulation), interfaced with a computer for digital readout, carrying a 25 mm porcine aortic valve. The cardiovascular simulator was programmed to mimic an elderly woman with aortic stenosis: 120/85 mmHg aortic pressure, 60 strokes/min (66.5 ml), 35% systole (2.8 l/min). Results: A total of 450 cardiac cycles was analysed. Stepwise expansion of the self-expanding stent valve with annular fixation (balloon-expandable stent valve) resulted in systolic ventricular increase from 120 to 121 mmHg (126 to 830 ± 76 mmHg)*, and left ventricular outflow obstruction with mean transvalvular gradient of 11 ± 1.5 mmHg (366 ± 202 mmHg)*, systolic aortic pressure dropped distal to the valve from 121 to 64.5 ± 2 mmHg (123 to 55 ± 30 mmHg) N.S., and output collapsed to 1.9 ± 0.06 l/min (0.71 ± 0.37 l/min* (before complete obstruction)). No valve migration occurred in either group. (* = p < 0.05). Conclusions: Implantation of this new self-expanding stent valve with annular fixation has little impact on haemodynamics and has the potential for working heart implantation in vivo. Flow reduction (rapid pacing) is not necessar

Gravitational wave background from Population III black hole formation

We study the generation of a stochastic gravitational wave (GW) background produced from a population of core-collapse supernovae, which form black holes in scenarios of structure formation. We obtain, for example, that the formation of a population (Population III) of black holes, in cold dark matter scenarios, could generate a stochastic GW background with a maximum amplitude of $h_{\rm BG} \simeq 10^{-24}$ and corresponding closure energy density of $\Omega_{\rm{GW}}\sim 10^{-7}$, in the frequency band $\nu_{\rm{obs}} \simeq 30-470 {\rm Hz}$ (assuming a maximum efficiency of generation of GWs, namely, $\epsilon_{\rm GW_{\rm max}} = 7\times 10^{-4}$) for stars forming at redshifts $z\simeq 30-10.$ We show that it will be possible in the future to detect this isotropic GW background by correlating signals of a pair of `advanced' LIGO observatories (LIGO III) at a signal-to-noise ratio of $\simeq 40$. We discuss what astrophysical information could be obtained from a positive (or even a negative) detection of such a GW background generated in scenarios such as those studied here. One of them is the possibility of obtaining the initial and final redshifts of the emission period from the observed spectrum of GWs.Comment: 10 pages (mn2e Latex), 3 eps figures, MNRAS (in press

Ancient mitochondrial and modern whole genomes unravel massive genetic diversity loss during near extinction of Alpine ibex

Population bottlenecks can have dramatic consequences for the health and long-term survival of a species. Understanding of historic population size and standing genetic variation prior to a contraction allows estimating the impact of a bottleneck on the species' genetic diversity. Although historic population sizes can be modelled based on extant genomics, uncertainty is high for the last 10–20 millenia. Hence, integrating ancient genomes provides a powerful complement to retrace the evolution of genetic diversity through population fluctuations. Here, we recover 15 high-quality mitogenomes of the once nearly extinct Alpine ibex spanning 8601 BP to 1919 CE and combine these with 60 published modern whole genomes. Coalescent demography simulations based on modern whole genomes indicate population fluctuations coinciding with the last major glaciation period. Using our ancient and historic mitogenomes, we investigate the more recent demographic history of the species and show that mitochondrial haplotype diversity was reduced to a fifth of the prebottleneck diversity with several highly differentiated mitochondrial lineages having coexisted historically. The main collapse of mitochondrial diversity coincides with elevated human population growth during the last 1–2 kya. After recovery, one lineage was spread and nearly fixed across the Alps due to recolonization efforts. Our study highlights that a combined approach integrating genomic data of ancient, historic and extant populations unravels major long-term population fluctuations from the emergence of a species through its near extinction up to the recent past

A Highly-Conserved Residue of the HIV-1-gp120 Inner Domain is Important for ADCC Responses Mediated by Anti-Cluster A Antibodies

Previous studies have shown that sera from HIV-1-infected individuals contain antibodies able to mediate antibody-dependent cellular cytotoxicity (ADCC). These antibodies preferentially recognize envelope glycoprotein (Env) epitopes induced upon CD4 binding. Here, we show that a highly conserved tryptophan at position 69 of the gp120 inner domain is important for ADCC mediated by anti-cluster A antibodies and sera from HIV-1-infected individuals

Impact of osteopathic manipulative treatment on range of motion of the pelvis during the one-sided tilt test: a pilot study

International audienc

Exploration of T cell immune responses by expression of a dominant-negative SHP1 and SHP2

SHP1 and SHP2 are SH2 domain-containing proteins which have inhibitory phosphatase activity when recruited to phosphorylated ITIMs and ITSMs on inhibitory immune receptors. Consequently, SHP1 and SHP2 are key proteins in the transmission of inhibitory signals within T cells, constituting an important point of convergence for diverse inhibitory receptors. Therefore, SHP1 and SHP2 inhibition may represent a strategy for preventing immunosuppression of T cells mediated by cancers hence improving immunotherapies directed against these malignancies. Both SHP1 and SHP2 contain dual SH2 domains responsible for localization to the endodomain of inhibitory receptors and a protein tyrosine phosphatase domain which dephosphorylates and thus inhibits key mediators of T cell activation. We explored the interaction of the isolated SH2 domains of SHP1 and SHP2 to inhibitory motifs from PD1 and identified strong binding of both SH2 domains from SHP2 and more moderate binding in the case of SHP1. We next explored whether a truncated form of SHP1/2 comprising only of SH2 domains (dSHP1/2) could act in a dominant negative fashion by preventing docking of the wild type proteins. When co-expressed with CARs we found that dSHP2 but not dSHP1 could alleviate immunosuppression mediated by PD1. We next explored the capacity of dSHP2 to bind with other inhibitory receptors and observed several potential interactions. In vivo we observed that the expression of PDL1 on tumor cells impaired the ability of CAR T cells to mediate tumor rejection and this effect was partially reversed by the co-expression of dSHP2 albeit at the cost of reduced CAR T cell proliferation. Modulation of SHP1 and SHP2 activity in engineered T cells through the expression of these truncated variants may enhance T cell activity and hence efficacy in the context of cancer immunotherapy

Tuning ultrafast electron thermalization pathways in a van der Waals heterostructure

Ultrafast electron thermalization - the process leading to Auger recombination, carrier multiplication via impact ionization and hot carrier luminescence - occurs when optically excited electrons in a material undergo rapid electron-electron scattering to redistribute excess energy and reach electronic thermal equilibrium. Due to extremely short time and length scales, the measurement and manipulation of electron thermalization in nanoscale devices remains challenging even with the most advanced ultrafast laser techniques. Here, we overcome this challenge by leveraging the atomic thinness of two-dimensional van der Waals (vdW) materials in order to introduce a highly tunable electron transfer pathway that directly competes with electron thermalization. We realize this scheme in a graphene-boron nitride-graphene (G-BN-G) vdW heterostructure, through which optically excited carriers are transported from one graphene layer to the other. By applying an interlayer bias voltage or varying the excitation photon energy, interlayer carrier transport can be controlled to occur faster or slower than the intralayer scattering events, thus effectively tuning the electron thermalization pathways in graphene. Our findings, which demonstrate a novel means to probe and directly modulate electron energy transport in nanoscale materials, represent an important step toward designing and implementing novel optoelectronic and energy-harvesting devices with tailored microscopic properties.Comment: Accepted to Nature Physic

Preventing misidentification of 25I-NBOH as 2C-I on routine GC-MS analyses

25I-NBOH is a novel psychoactive substance (NPS) recently reported to have been found on blotter paper samples seized on the streets of Brazil, and used as a replacement for the NBOMes now scheduled in many countries. The presence of this NPS on the street market may go undetected, because the most widely and routinely utilised analytical technique for drug sample analyses is gas chromatography-mass spectrometry (GC-MS), which can misidentify 25I-NBOH (and indeed the other members of the NBOH series), because of its degradation into 2C-I (and corresponding 2C for the other members of the series) within the injector, unless a derivatization procedure is employed, which is often non-standard. While direct detection of 25I-NBOH under routine GC-MS conditions is still achieved, a slight adjustment in the standard GC-MS method, including shortening of the solvent delay window, was found to enable the detection of an additional peak due to 25I-NBOH degradation. Consequently, the presence of this secondary early chromatographic peak allowed for the distinction between 25I-NBOH and 2C-I using routine GC-MS without resorting to derivatization (or other analytical processes), thus preventing misidentification of 25I-NBOH as 2C-I. © 2017 Japanese Association of Forensic Toxicology and Springer Japa