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α-Synuclein (αS) is a presynaptic protein that binds to cell membranes and is linked to Parkinson’s disease (PD). Binding of αS to membranes is a likely first step in the molecular pathophysiology of PD. The αS molecule can adopt multiple conformations, being largely disordered in water, adopting a β-sheet conformation when present in amyloid fibrils, and forming a dynamic multiplicity of α-helical conformations when bound to lipid bilayers and related membrane-mimetic surfaces. Multiscale molecular dynamics simulations in conjunction with nuclear magnetic resonance (NMR) and cross-linking mass spectrometry (XLMS) measurements are used to explore the interactions of αS with an anionic lipid bilayer. The simulations and NMR measurements together reveal a break in the helical structure of the central non-amyloid-β component (NAC) region of αS in the vicinity of residues 65–70, which may facilitate subsequent oligomer formation. Coarse-grained simulations of αS starting from the structure of αS when bound to a detergent micelle reveal the overall pattern of protein contacts to anionic lipid bilayers, while subsequent all-atom simulations provide details of conformational changes upon membrane binding. In particular, simulations and NMR data for liposome-bound αS indicate incipient β-strand formation in the NAC region, which is supported by intramolecular contacts seen via XLMS and simulations. Markov state models based on the all-atom simulations suggest a mechanism of conformational change of membrane-bound αS via a dynamic helix break in the region of residue 65 in the NAC region. The emergent dynamic model of membrane-interacting αS advances our understanding of the mechanism of PD, potentially aiding the design of novel therapeutic approaches.

Peptide vaccines have many potential advantages over conventional ones including low cost, lack of need for cold-chain storage, safety and specificity. However, it is well known that approximately 90% of B-cell epitopes (BCEs) are discontinuous in nature making it difficult to mimic them for creating vaccines. In this study, the degree of discontinuity in B-cell epitopes and their conformational nature is examined. The discontinuity of B-cell epitopes is analyzed by defining ‘regions’ (consisting of at least three antibody-contacting residues each separated by ≤3 residues) and small fragments (antibody-contacting residues that do not satisfy the requirements for a region). Secondly, an algorithm has been developed that classifies each region's shape as straight, curved or folded on the basis that straight and folded regions are more likely to retain their native conformation as isolated peptides. We have investigated the structures of 488 B-cell epitopes from which 1282 regions and 1018 fragments have been identified. 90% of epitopes have five or fewer regions and five or fewer fragments with 14% containing only one region and 4% being truly linear (i.e. having one region and no fragments). Of the 1282 regions, 508 are straight in shape, 626 are curved and 148 are folded.

Summary: We describe therapeutic monoclonal antibodies isolated from human volunteers vaccinated with recombinant adenovirus expressing Ebola virus glycoprotein (EBOV GP) and boosted with modified vaccinia virus Ankara. Among 82 antibodies isolated from peripheral blood B cells, almost half neutralized GP pseudotyped influenza virus. The antibody response was diverse in gene usage and epitope recognition. Although close to germline in sequence, neutralizing antibodies with binding affinities in the nano- to pico-molar range, similar to “affinity matured” antibodies from convalescent donors, were found. They recognized the mucin-like domain, glycan cap, receptor binding region, and the base of the glycoprotein. A cross-reactive cocktail of four antibodies, targeting the latter three non-overlapping epitopes, given on day 3 of EBOV infection, completely protected guinea pigs. This study highlights the value of experimental vaccine trials as a rich source of therapeutic human monoclonal antibodies. : Most antibodies used for Ebola virus treatment originate from convalescent donors or highly immunized animals. Rijal et al. find that monoclonal antibodies isolated early after vaccination from humans can be powerfully therapeutic, despite the relative immaturity of their sequences. Vaccine trials therefore can provide a valuable source of therapeutic antibodies. Keywords: Ebola virus, human monoclonal antibodies, immunotherapy, therapeutic antibodies, guinea pig model, Ebola virus glycoprotein epitopes, E-S-FLU virus, antibody binding kinetics, affinity maturation

Two decades after their discovery, stapled peptide methodologies have evolved to a point where they can be used with confidence to generate therapeutic leads. Research groups across the world are testing innovative methodologies for their design, with dozens of publications released every month. A number of stapled peptide drug candidates have recently entered clinical trials. In this review, we provide an overview of successful methods for their construction, highlight trends in the deposited crystal structures of stapled peptide complexed to their targets and discuss properties that contribute towards improved pharmacological profiles.

Interleukin (IL)-17A is a key driver of inflammation and the principal target of anti-IL-17 therapeutic monoclonal antibodies. IL-17A, and its structurally similar family member IL-17F, have been shown to be functionally dysregulated in certain human immune-mediated inflammatory diseases such as psoriasis, psoriatic arthritis, and axial spondyloarthritis. Given the overlapping biology of these two cytokines, we postulated that dual neutralization of IL-17A and IL-17F may provide a greater depth of clinical response in IL-17-mediated diseases than IL-17A inhibition alone. We identified 496.g1, a humanized antibody with strong affinity for IL-17A but poor affinity for IL-17F. Affinity maturation of 496.g1 to 496.g3 greatly enhanced the affinity of the Fab fragment for IL-17F while retaining strong binding to IL-17A. As an IgG1, the affinity for IL-17A and IL-17F was 3.2 pM and 23 pM, respectively. Comparison of 496.g3 IgG1 with the commercially available anti-IL-17A monoclonal antibodies ixekizumab and secukinumab, by surface plasmon resonance and in a human in vitro IL-17A functional assay, showed that 496.g3 and ixekizumab display equivalent affinity for IL-17A, and that both antibodies are markedly more potent than secukinumab. In contrast to ixekizumab and secukinumab, 496.g3 exhibited the unique feature of also being able to neutralize the biological activity of IL-17F. Therefore, antibody 496.g3 was selected for clinical development for its ability to neutralize the biologic function of both IL-17A and IL-17F and was renamed bimekizumab (formerly UCB4940). Early clinical data in patients with psoriasis, in those with psoriatic arthritis, and from the Phase 2 studies in psoriasis, psoriatic arthritis, and ankylosing spondylitis, are encouraging and support the targeted approach of dual neutralization of IL-17A and IL-17F. Taken together, these findings provide the rationale for the continued clinical evaluation of bimekizumab in patients with immune-mediated inflammatory diseases.

In Alzheimer’s disease (AD) and other tauopathies, the cytosolic protein Tau misfolds and forms intracellular aggregates which accumulate within the brain leading to neurodegeneration. Clinical progression is tightly linked to the progressive spread of Tau pathology throughout the brain, and several lines of evidence suggest that Tau aggregates or “seeds” may propagate pathology by spreading from cell to cell in a “prion like” manner. Accordingly, blocking the spread of extracellular seeds with an antibody could be a viable therapeutic approach. However, as the structure of Tau seeds is unknown, it is only possible to rationally design therapeutic Tau antibodies by making a priori assumptions. To avoid this, we developed a robust and quantitative cell based assay and employed an unbiased screening approach to identify the antibody with the highest activity against human Tau seeds. The selected antibody (D), directed to the mid-region of Tau (amino acids 235–250), potently blocked the seeding of human AD Tau and was also fully efficacious against seeds from progressive supranuclear palsy. When we compared this antibody with previously described reference antibodies, we were surprised to find that none of these antibodies showed comparable efficacy against human pathological seeds. Our data highlight the difficulty of predicting antibody accessible epitopes on pathological Tau seeds and question the potential efficacy of some of the Tau antibodies that are currently in clinical development. Electronic supplementary material The online version of this article (10.1007/s00401-018-1911-2) contains supplementary material, which is available to authorized users.

We generated an anti-albumin antibody, CA645, to link its Fv domain to an antigen-binding fragment (Fab), thereby extending the serum half-life of the Fab. CA645 was demonstrated to bind human, cynomolgus, and mouse serum albumin with similar affinity (1–7 nM), and to bind human serum albumin (HSA) when it is in complex with common known ligands. Importantly for half-life extension, CA645 binds HSA with similar affinity within the physiologically relevant range of pH 5.0 – pH 7.4, and does not have a deleterious effect on the binding of HSA to neonatal Fc receptor (FcRn). A crystal structure of humanized CA645 Fab in complex with HSA was solved and showed that CA645 Fab binds to domain II of HSA. Superimposition with the crystal structure of FcRn bound to HSA confirmed that CA645 does not block HSA binding to FcRn. In mice, the serum half-life of humanized CA645 Fab is 84.2 h. This is a significant extension in comparison with < 1 h for a non-HSA binding CA645 Fab variant. The Fab-HSA structure was used to design a series of mutants with reduced affinity to investigate the correlation between the affinity for albumin and serum half-life. Reduction in the affinity for MSA by 144-fold from 2.2 nM to 316 nM had no effect on serum half-life. Strikingly, despite a reduction in affinity to 62 µM, an extension in serum half-life of 26.4 h was still obtained. CA645 Fab and the CA645 Fab-HSA complex have been deposited in the Protein Data Bank (PDB) with accession codes, 5FUZ and 5FUO, respectively.

Modified peptides, such as stapled peptides, which replicate the structure of α-helical protein segments, represent a potential therapeutic advance. However, the 3D solution structure of these stapled peptides is rarely explored beyond the acquisition of circular dichroism (CD) data to quantify bulk peptide helicity; the detailed backbone structure, which underlies this, is typically undefined. Diastereomeric stapled peptides based on helical sections of three proteins (αSyn, Cks1 and CK1α) were generated; their overall helicity was quantified by CD; and the most helical peptide from each series was selected for structural analysis. Solution-phase models for the optimised peptides were generated using NMR-derived restraints and a modified CHARMM22 force field. Comparing these models with PDB structures allowed deviation between the stapled peptides and critical helical regions to be evaluated. These studies demonstrate that CD alone is not sufficient to assess the structural fidelity of a stapled peptide.

Protein:protein interactions are fundamental in living organism homeostasis. Here we introduce VHH6, a junctional epitope antibody capable of specifically recognizing a neo-epitope when two proteins interact, albeit transiently, to form a complex. Orthogonal biophysical techniques have been used to prove the “junctional epitope” nature of VHH6, a camelid single domain antibody recognizing the IL-6–gp80 complex but not the individual components alone. X-ray crystallography, HDX-MS and SPR analysis confirmed that the CDR regions of VHH6 interact simultaneously with IL-6 and gp80, locking the two proteins together. At the cellular level, VHH6 was able to alter the response of endothelial cells to exogenous IL-6, promoting a sustained STAT3 phosphorylation signal, an accumulation of IL-6 in vesicles and an overall pro-inflammatory phenotype supported further by transcriptomic analysis. Junctional epitope antibodies, like VHH6, not only offer new opportunities in screening and structure-aided drug discovery, but could also be exploited as therapeutics to modulate complex protein:protein interactions.

Interleukin-6 (IL-6) is a critical regulator of the immune system and has been widely implicated in autoimmune disease. Here, we describe the discovery and characterization of olokizumab, a humanized antibody to IL-6. Data from structural biology, cell biology and primate pharmacology demonstrate the therapeutic potential of targeting IL-6 at “Site 3”, blocking the interaction with the signaling co-receptor gp130.

Camel antibodies have been widely investigated, but work has focused upon the unique heavy chain antibodies found across camelid species. These are homodimers, devoid of light chains and the first constant heavy chain domain. Camelid species also display conventional hetero-tetrameric antibodies with identical pairs of heavy and light chains; in Camelus dromedarius these constitute 25% of circulating antibodies. Few investigations have been made on this subset of antibodies and complete conventional camel IgG sequences have not been reported.Here we study the sequence diversity of functional variable and constant regions observed in 57 conventional heavy, 18 kappa and 35 lambda light chains of C. dromedarius and Camelus bactrianus. We detail sequences of the full kappa and lambda light chain, variable and CH1 region for IgG1a and IgG1b and the CH2 and CH3 region for IgG1a. The majority (60%) of IgG1 variable region sequences aligned with the human IgHV3 family (clan III) and had leader sequences beginning with MELG whereas the remaining sequences aligned with the IgHV4 (clan II) and had leader sequences beginning with MRLL. Distinct differences in CDR length were observed between the two; where CDR1 was typically 5 and 7 residues and CDR2 at 17 and 16 residues, respectively. CDR3 length of IgHV4 (range 11 to 20) was closer to that typical of VHH antibodies than that of IgHV3 (range 3 to 18 residues). Designed oligonucleotide primers have enabled identification of paired heavy and light chains of conventional camel antibodies from individual B cell clones.

Structural antibody database (SAbDab; http://opig.stats.ox.ac.uk/webapps/sabdab) is an online resource containing all the publicly available antibody structures annotated and presented in a consistent fashion. The data are annotated with several properties including experimental information, gene details, correct heavy and light chain pairings, antigen details and, where available, antibody-antigen binding affinity. The user can select structures, according to these attributes as well as structural properties such as complementarity determining region loop conformation and variable domain orientation. Individual structures, datasets and the complete database can be downloaded.

Therapeutic and diagnostic applications of monoclonal antibodies often require careful selection of binders that recognize specific epitopes on the target molecule to exert a desired modulation of biological function. Here we present a proof-of-concept application for the rational design of an epitope-specific antibody binding with the target protein Keap1, by grafting pre-defined structural interaction patterns from the native binding partner protein, Nrf2, onto geometrically matched positions of a set of antibody scaffolds. The designed antibodies bind to Keap1 and block the Keap1-Nrf2 interaction in an epitope-specific way. One resulting antibody is further optimised to achieve low-nanomolar binding affinity by in silico redesign of the CDRH3 sequences. An X-ray co-crystal structure of one resulting design reveals that the actual binding orientation and interface with Keap1 is very close to the design model, despite an unexpected CDRH3 tilt and VH/VL interface deviation, which indicates that the modelling precision may be improved by taking into account simultaneous CDR loops conformation and VH/VL orientation optimisation upon antibody sequence change. Our study confirms that, given a pre-existing crystal structure of the target protein-protein interaction, hotspots grafting with CDR loop swapping is an attractive route to the rational design of an antibody targeting a pre-selected epitope.

A number of secreted cytokines, such as interleukin-6 (IL-6), are attractive targets for the treatment of inflammatory diseases. We have determined the solution structure of mouse IL-6 to assess the functional significance of apparent differences in the receptor interaction sites (IL-6Rα and gp130) suggested by the fairly low degree of sequence similarity with human IL-6. Structure-based sequence alignment of mouse IL-6 and human IL-6 revealed surprising differences in the conservation of the two distinct gp130 binding sites (IIa and IIIa), which suggests a primacy for site III-mediated interactions in driving initial assembly of the IL-6/IL-6Rα/gp130 ternary complex. This is further supported by a series of direct binding experiments, which clearly demonstrate a high affinity IL-6/IL-6Rα-gp130 interaction via site III but only weak binding via site II. Collectively, our findings suggest a pathway for the evolution of the hexameric, IL-6/IL-6Rα/gp130 signaling complex and strategies for therapeutic targeting. We propose that the signaling complex originally involved specific interactions between IL-6 and IL-6Rα (site I) and between the D1 domain of gp130 and IL-6/IL-6Rα (site III), with the later inclusion of interactions between the D2 and D3 domains of gp130 and IL-6/IL-6Rα (site II) through serendipity. It seems likely that IL-6 signaling benefited from the evolution of a multipurpose, nonspecific protein interaction surface on gp130, now known as the cytokine binding homology region (site II contact surface), which fortuitously contributes to stabilization of the IL-6/IL-6Rα/gp130 signaling complex.

Refugees seeking to settle in a country other than their own are a fact of life in our global society today. A counsellor faced with supporting a client who is a refugee may be more effective by approaching this work from a point of view that is as inclusive and holistic as possible. This paper presents an approach to counselling refugee clients based on the Integral Theory and Psychology of Ken Wilber and associates, focusing on at least four basic dimensions of human experience. The four dimensions are the subjective and the objective of the individual and the collective, or the ‘I‘, ‘It‘, ‘We‘ and ‘Its‘ realms of reality, as they arise in the client's life. The counsellor is charged with assisting the refugee client to attain healthier functioning in every one of these four dimensions, while giving equal value to each and not privileging any one of them without good reason. It should be noted that, while Integral Theory is in itself not a new therapy, it allows the counsellor to situate anything that a...

Motivation: Antibodies are currently the most important class of biopharmaceuticals. Development of such antibody-based drugs depends on costly and time-consuming screening campaigns. Computational techniques such as antibody–antigen docking hold the potential to facilitate the screening process by rapidly providing a list of initial poses that approximate the native complex. Results: We have developed a new method to identify the epitope region on the antigen, given the structures of the antibody and the antigen—EpiPred. The method combines conformational matching of the antibody–antigen structures and a specific antibody–antigen score. We have tested the method on both a large non-redundant set of antibody–antigen complexes and on homology models of the antibodies and/or the unbound antigen structure. On a non-redundant test set, our epitope prediction method achieves 44% recall at 14% precision against 23% recall at 14% precision for a background random distribution. We use our epitope predictions to rescore the global docking results of two rigid-body docking algorithms: ZDOCK and ClusPro. In both cases including our epitope, prediction increases the number of near-native poses found among the top decoys. Availability and implementation: Our software is available from http://www.stats.ox.ac.uk/research/proteins/resources. Contact: deane@stats.ox.ac.uk Supplementary information: Supplementary Data are available at Bioinformatics online.

Antibodies are a class of proteins indispensable for the vertebrate immune system. The general architecture of all antibodies is very similar, but they contain a hypervariable region which allows millions of antibody variants to exist, each of which can bind to different molecules. This binding malleability means that antibodies are an increasingly important category of biopharmaceuticals and biomarkers. We present Antibody i-Patch, a method that annotates the most likely antibody residues to be in contact with the antigen. We show that our predictions correlate with energetic importance and thus we argue that they may be useful in guiding mutations in the artificial affinity maturation process. Using our predictions as constraints for a rigid-body docking algorithm, we are able to obtain high-quality results in minutes. Our annotation method and re-scoring system for docking achieve their predictive power by using antibody-specific statistics. Antibody i-Patch is available from http://www.stats.ox.ac.uk/research/proteins/resources.

The concept of GRASS (Geographic Resources Analysis Support System) as an open system has created a favourable environment for integration of process based modelling and GIS. To support this integration a new generation of tools is being developed in the following areas: (a) interpolation from multidimensional scattered point data, (b) analysis of surfaces and hypersurfaces, (c) modelling of spatial processes and, (d) 3D dynamic visualization. Examples of two applications are given-spatial and temporal modelling of erosion and deposition, and multivariate interpolation and visualization of nitrogen concentrations in the Chesapeake Bay.

A gene transfer vector has been developed utilising anionic liposomes as a carrier of plasmid DNA (pEGlacZ, 7.6 kb) to transfect CD3+ T lymphocytes (Jurkat cells). The plasmid DNA that contained the Escherichia coli beta-galactosidase reporter gene was condensed using poly-l-lysine of molecular mass 20,700 (PLK99) to form a polyplex which was interacted with several anionic liposome formulations to form lipopolyplexes. The liposome formulations where based on dioleoylphosphatidylethanolamine (DOPE) in combination with cholesterol and dioleoylphosphatidylcholine (DOPC) and oleic acid, or dimyristoylphosphatidylethanolamine (DMPE). For targeting to the Jurkat cells distearoylphosphatidylethanolamine (DSPE) linked to poly (ethylene glycol) molecular mass 2,000 and coupled to anti-CD3 antibody was incorporated. The polyplexes and lipopolyplexes were characterised in terms of size, zeta potential, agarose gel electrophoresis and electron microscopy and the permeability of the lipopolyplexes to liposome-encapsulated glucose was determined. The polyplexes consisted of a mixed population of rod-like structures (53-160 nm long and 23-31 nm diameter) and spheres (18-30 nm diameter). The lipopolyplexes retained a permeability barrier although were more permeable to glucose than their component liposomes. The poly-l-lysine condensing agent was still susceptible to pronase digestion suggesting that the polyplex was associated with the outer surface of the liposome. The lipopolyplexes with lipid composition DOPE/cholesterol/OA/DSPE-PEG2000 anti-CD3+ PLK99-plasmid DNA had significant gene transfer activity, as monitored by beta-galactosidase expression, that depended on the charge ratio of the component polyplex and the lipid/DNA weight ratio. The anti-CD3 antibody, the liposomal lipid and pH sensitivity were essential for transfection activity.

A Chief Programmer Team is a concept coupling functionally specialized programming organization with the use of software engineering techniques, such as structured programming and top-down development, to produce effective software systems of high quality. The idea originated with Harlan D. Mills, who in 1968 was concerned about the inefficiencies apparent in large-scale software development. He believed that a structured, multi-disciplinary organization using standardized methods and tools could develop systems of higher quality and achieve improved productivity.

We have quantified the effects of the regiochemical distribution of positive charges along the polyamine moiety in lipopolyamines for DNA molecular recognition. High affinity binding leads to charge neutralisation, DNA condensation and ultimately to lipofection. Binding affinities for calf thymus DNA were determined using an ethidium bromide displacement assay and condensation was detected by changes in turbidity using light scattering. The in vitro transfection competence of cholesterol polyamine carbamates was measured in CHO cells. In the design of DNA condensing and transfecting agents for non-viral gene therapy, the interrelationship of ammonium ions, not just their number, must be considered.

A comparison was made between the murine anti-MUC1 antibody BC2 (which reacts with the peptide epitope APDTR) and the "humanised" antibody hCTMO1 from CellTech, which reacts with the MUC1 epitope RPAP. Preliminary studies demonstrated that hCTMO1 was a "good" antibody whereas BC2 was not. Various parameters were determined and conclusions reached. (a) Affinity: the affinity of hCTMO1 was 2.60 x 10(7) M(-1) and that of BC2 was 1.36 x 10(7) M(-1); we did not consider these numbers to be substantially different, although hCTMO1 was clearly of higher affinity than BC2. (b) On/off rate at 4 degrees C: both antibodies bound effectively to the MUC-1 transfectant MOR5-CF2; the association rate for hCTMO1 was 3.8 times that of BC2 and the dissociation rate for BC2 was twice as fast as that of hCTMO1. (c) On/off rates at 37 degrees C: at 37 degrees C the association rate for hCTMO1 was greater than that of BC2. (d) Internalization: hCTMO1 was also more efficient at internalising bound antibody; 70% of bound hCTMO1 was internalised, whilst 6% of bound BC2 was internalised. From these studies it was clear that, while hCTMO1 was of similar affinity to BC2, the faster uptake and internalisation and lower off rate indicated that it was likely to be a superior antibody; this was proven in vivo. (e) Localisation: hCTMO1 bound much better in vivo than BC2 (68% compared to 28%). (f) Therapeutic experiments: BC2-idarubicin conjugates were essentially ineffective in eradicating tumours in mice whereas hCTMO1-idarubicin had a dramatic effect on breast cancer tumour cells growing in mice. We conclude that the simple measurements on/off rates and internalisation at 37 degrees C are the most important parameters to use to determine antibody effectiveness, prior to embarking on clinical studies.

Background Certolizumab pegol (CZP) is a PEGylated, Fc-free anti-TNF that lacks the Fc portion found in monoclonal antibodies. Infliximab (IFX) and adalimumab (ADA) are both antibodies, while etanercept (ETA) is a receptor fusion protein, and all three of these anti-TNFs have an IgG1 Fc. In mothers treated with CZP, it has been reported that lower levels of CZP, compared to ADA or IFX, are transferred to the neonate.[1][1] It has been suggested this transfer differential may be due to the one-way active transport of antibodies across the placenta thought to be mediated by the neonatal Fc receptor (FcRn). However, anti-TNF binding to FcRn, and FcRn-mediated transcytosis across a cell layer, have not been studied. Objectives To quantify binding of the anti-TNFs CZP, IFX, ADA and ETA to FcRn and to measure FcRn-mediated transcytosis of these agents across a cell layer. Methods A Biacore™ assay was used to determine the binding of CZP, ADA and IFX to human FcRn. Anti-TNFs were passed over an FcRn-coated chip for 5 minutes at a range of concentrations from 21-670nM to determine the on-binding rate; a buffer at pH 6.0 was used to allow optimum binding. The off-rate was followed for a further 5 minutes by running buffer alone over the chip. MDCK II cells transfected with human FcRn were used to measure FcRn-mediated transcytosis across a cell layer using a pH 5.9 buffer on the apical side and pH 7.2 on the basolateral side. The anti-TNFs and the control antibody (P146), which possessed a Fc modified to prevent binding to FcRn, were biotinylated to allow visualization. The amount of each anti-TNF transcytosed across the cell layer over 4 hours was measured by MSD assay. Results IFX (132nM) and ADA (225nM) had relatively high binding affinity to FcRn while the binding affinity of ETA to FcRn was approximately 5 to 10-fold lower (1500nM), similar to previously reported results.2 In contrast, CZP did not bind to the FcRn with any measurable affinity. The levels of transcytosis seen with IFX and ADA were 249.6ng/mL and 159.5ng/mL, respectively (mean of 3 experiments), over 4 hours. Transcytosis of ETA (81.3ng/mL) was lower than that of ADA and IFX. In contrast, the level of CZP transcytosis was significantly lower, at 3.2ng/mL, than that observed with the other anti-TNFs tested. The control antibody P146 also showed a low level of transfer at 5.9ng/mL. Since neither the control antibody nor CZP bind to FcRn, the levels detected are probably due to a low level of non-specific leakage across the cell layer. Conclusions This is the first report to quantify the binding of anti-TNFs to FcRn and their FcRn-mediated transcytosis across a cell layer. CZP does not have an Fc and thus did not bind to FcRn. Moreover, no FcRn-mediated CZP transcytosis was detected. In contrast, ADA and IFX had a relatively high binding affinity to FcRn and were actively transcytosed across the cell layer. ETA showed lower binding affinity to FcRn and subsequent transcytosis, compared to IFX and ADA, but FcRn-mediated transport could still be measured. These results explain the previously observed active transport of anti-TNFs across the placenta seen in patients treated with IFX and ADA, whereas only low levels were observed with CZP.1 References 1. Mahadevan U. Clin Gastroenterol Hepatol 2012 [epub ahead of print]; 2. Suzuki T. J Immunol 2010;184(4):1968-1976. Acknowledgements The authors acknowledge Costello Medical Consulting for writing and editorial assistance which was funded by UCB Pharma. Disclosure of Interest T. Baker Employee of: UCB Pharma, L. Kevorkian Employee of: UCB Pharma, A. Nesbitt Shareholder of: UCB Pharma, Employee of: UCB Pharma [1]: #p-6

ObjectiveInterleukin (IL)-17A has emerged as pivotal in driving tissue pathology in immune-mediated inflammatory diseases. The role of IL-17F, sharing 50% sequence homology and overlapping biological function, remains less clear. We hypothesised that IL-17F, together with IL-17A, contributes to chronic tissue inflammation, and that dual neutralisation may lead to more profound suppression of inflammation than inhibition of IL-17A alone.MethodsPreclinical experiments assessed the role of IL-17A and IL-17F in tissue inflammation using disease-relevant human cells. A placebo-controlled proof-of-concept (PoC) clinical trial randomised patients with psoriatic arthritis (PsA) to bimekizumab (n=39) or placebo (n=14). Safety, pharmacokinetics and clinical efficacy of multiple doses (weeks 0, 3, 6 (240 mg/160 mg/160 mg; 80 mg/40 mg/40 mg; 160 mg/80 mg/80 mg and 560 mg/320 mg/320 mg)) of bimekizumab, a humanised monoclonal IgG1 antibody neutralising both IL-17A and IL-17F, were investigated.ResultsIL-17F induced qualitatively similar inflammatory responses to IL-17A in skin and joint cells. Neutralisation of IL-17A and IL-17F with bimekizumab more effectively suppressed in vitro cytokine responses and neutrophil chemotaxis than inhibition of IL-17A or IL-17F alone. The PoC trial met both prespecified efficacy success criteria and showed rapid, profound responses in both joint and skin (pooled top three doses vs placebo at week 8: American College of Rheumatology 20% response criteria 80.0% vs 16.7% (posterior probability >99%); Psoriasis Area and Severity Index 100% response criteria 86.7% vs 0%), sustained to week 20, without unexpected safety signals.ConclusionsThese data support IL-17F as a key driver of human chronic tissue inflammation and the rationale for dual neutralisation of IL-17A and IL-17F in PsA and related conditions.Trial registration numberNCT02141763; Results.

Antibodies to tumor necrosis factor (anti-TNF) are used to treat inflammatory diseases, which often affect women of childbearing age. The active transfer of these antibodies across the placenta by binding of the Fc-region to the neonatal Fc receptor (FcRn) may result in adverse fetal or neonatal effects. In contrast to other anti-TNFs, certolizumab pegol lacks an Fc-region. The objective of this study was to determine whether the structure of certolizumab pegol limits active placental transfer.Binding affinities of certolizumab pegol, infliximab, adalimumab and etanercept to human FcRn and FcRn-mediated transcytosis were determined using in vitro assays. Human placentas were perfused ex vivo to measure transfer of certolizumab pegol and positive control anti-D IgG from the maternal to fetal circulation.FcRn binding affinity (KD) was 132nM, 225nM and 1500nM for infliximab, adalimumab and etanercept, respectively. There was no measurable certolizumab pegol binding affinity, similar to that of the negative control. FcRn-mediated transcytosis across a cell layer (mean±SD; n=3) was 249.6±25.0 (infliximab), 159.0±20.2 (adalimumab) and 81.3±13.1ng/mL (etanercept). Certolizumab pegol transcytosis (3.2±3.4ng/mL) was less than the negative control antibody (5.9±4.6ng/mL). No measurable transfer of certolizumab pegol from the maternal to the fetal circulation was observed in 5 out of 6 placentas that demonstrated positive-control IgG transport in the ex vivo perfusion model.Together these results support the hypothesis that the unique structure of certolizumab pegol limits its transfer through the placenta to the fetus and may be responsible for previously reported differences in transfer of other anti-TNFs from mother to fetus.

The molding of lens blanks has developed over the years into a highly sophisticated and exacting art.

A new type of programming methodology, built around structured programming ideas, has been gaining widespread acceptance for production programming. This paper discusses how this methodology has been introduced into a large production programming organization. Finally it analyzes the advantages and disadvantages of each component of the methodology and recommends ways it can be introduced in a conventional programming environment.