Process development for a flexible vaccine vector platform based on recombinant life virus

Vaccines are one of the most important, safe and efficient interventions to protect people from illness, disability and death. In recent years several new viral outbreaks where no vaccines are currently available were reported worldwide. Therefore, the development of flexible processes for the production of vaccines is urgently needed. This project aims at developing a platform process for the production of different viral vaccines. The core technology is based on the fact that large recombinant genes coding for selected, foreign antigens can be inserted into the genome of a well-established virus vaccination vector. The vaccine delivers the selected antigens directly to macrophages and dendritic cells, the most potent and effective antigen-presenting cells, thereby triggering a specific immune response to the selected antigens. As a replicating vector, the vaccine continuously expresses antigens even after immunization. This setup results in a powerful, antigen-focused immune response, which is expected to confer long-term immunity as shown for the measles vaccine. The challenges in production process design for such a vaccine are the establishment of a robust cell expansion and infection strategy as well the development of efficient downstream processing methods including several chromatography principals, ultra-diafiltration and employment of bio recognition principles. The implementation of a meaningful real-time process monitoring/characterization concept furthermore serves as a basis for reliable in-process control strategies (e.g. the prediction of the optimal infection/harvesting time point)

The prognostic value of polymorphonuclear leukocyte elastase in patients with primary breast cancer

A variety of serine proteases, including urokinase-type plasminogen activator (uPA), plasmin,and polymorphonuclear leukocyte elastase (PMN-E), have been implicated in the processes of tumor cell invasion and metastasis. Besides degrading of matrix proteins, PMN-E has been shown to be able to cleave and inactivate plasminogen activator inhibitor-1 (PAI-1), the main inhibitor of uPA, and alpha2-antiplasmin, the natural inhibitor of plasmin, thus enabling an uncontrolled matrix degradation by the fibrinolytic enzymes. Because only limited data are available on a relationship between the tumor level of PMN-E and prognosis in primary breast cancer patients, in the present study we have measured with an ELISA the levels of PMN-E (in complex with alpha1-proteinase inhibitor) in cytosolic extracts of 1143 primary breast tumors. Levels of complexed PMN-E have been correlated with the lengths of metastasis-free survival (MFS), relapse-free survival, and overall survival, and a comparison was made with data previously obtained for uPA and PAI-1. Our results show that patients with a high PMN-E level in their primary tumor had a rapid relapse and an early death compared with patients with a low tumor level of PMN-E. This held true for node-negative and node-positive subgroups of patients as well. The relationship of PMN-E with a poor prognosis was especially obvious during short-term follow-up (0-60 months). In Cox multivariate regression analysis, corrected for the traditional prognostic factors, PMN-E was an independent prognostic factor, and high levels of PMN-E were associated with a poor MFS [hazard ratio (HR), 1.63; 95% confidence interval (CI), 1.23-2.16; P < 0.001], relapse-free survival (HR, 1.45; 95% CI, 1.10-1.89; P = 0.01), and overall survival (HR, 1.64; 95% CI, 1.20-2.23; P = 0.003). Furthermore, in all three multivariate models, PMN-E still added significantly to the model after the additional inclusion of the uPA. PMN-E was an independent prognostic factor for MFS even in the multivariate analysis including the traditional clinical prognostic factors and the strong established biochemical prognostic factors uPA and PAI-1. Our present study suggests that PMN-E is associated with breast cancer metastasis, and knowledge of the tumor PMN-E status might be helpful in selecting the appropriate individualized (adjuvant) treatment for patients with breast cancer

Ability of 18F-FDG Positron Emission Tomography Radiomics and Machine Learning in Predicting KRAS Mutation Status in Therapy-Naive Lung Adenocarcinoma.

OBJECTIVE Considering the essential role of KRAS mutation in NSCLC and the limited experience of PET radiomic features in KRAS mutation, a prediction model was built in our current analysis. Our model aims to evaluate the status of KRAS mutants in lung adenocarcinoma by combining PET radiomics and machine learning. METHOD Patients were retrospectively selected from our database and screened from the NSCLC radiogenomic dataset from TCIA. The dataset was randomly divided into three subgroups. Two open-source software programs, 3D Slicer and Python, were used to segment lung tumours and extract radiomic features from 18F-FDG-PET images. Feature selection was performed by the Mann-Whitney U test, Spearman's rank correlation coefficient, and RFE. Logistic regression was used to build the prediction models. AUCs from ROCs were used to compare the predictive abilities of the models. Calibration plots were obtained to examine the agreements of observed and predictive values in the validation and testing groups. DCA curves were performed to check the clinical impact of the best model. Finally, a nomogram was obtained to present the selected model. RESULTS One hundred and nineteen patients with lung adenocarcinoma were included in our study. The whole group was divided into three datasets: a training set (n = 96), a validation set (n = 11), and a testing set (n = 12). In total, 1781 radiomic features were extracted from PET images. One hundred sixty-three predictive models were established according to each original feature group and their combinations. After model comparison and selection, one model, including wHLH_fo_IR, wHLH_glrlm_SRHGLE, wHLH_glszm_SAHGLE, and smoking habits, was validated with the highest predictive value. The model obtained AUCs of 0.731 (95% CI: 0.619~0.843), 0.750 (95% CI: 0.248~1.000), and 0.750 (95% CI: 0.448~1.000) in the training set, the validation set and the testing set, respectively. Results from calibration plots in validation and testing groups indicated that there was no departure between observed and predictive values in the two datasets (p = 0.377 and 0.861, respectively). CONCLUSIONS Our model combining 18F-FDG-PET radiomics and machine learning indicated a good predictive ability of KRAS status in lung adenocarcinoma. It may be a helpful non-invasive method to screen the KRAS mutation status of heterogenous lung adenocarcinoma before selected biopsy sampling

Calcium binding to a disordered domain of a type III-secreted protein from a coral pathogen promotes secondary structure formation and catalytic activity

Strains of the Gram-negative bacterium Vibrio coralliilyticus cause the bleaching of corals due to decomposition of symbiotic microalgae. The V. coralliilyticus strain ATCC BAA-450 (Vc450) encodes a type III secretion system (T3SS). The gene cluster also encodes a protein (locus tag VIC_001052) with sequence homology to the T3SS-secreted nodulation proteins NopE1 and NopE2 of Bradyrhizobium japonicum (USDA110). VIC_001052 has been shown to undergo auto-cleavage in the presence of Ca2+ similar to the NopE proteins. We have studied the hitherto unknown secondary structure, Ca2+-binding affinity and stoichiometry of the "metal ion-inducible autocleavage" (MIIA) domain of VIC_001052 which does not possess a classical Ca2+-binding motif. CD and fluorescence spectroscopy revealed that the MIIA domain is largely intrinsically disordered. Binding of Ca2+ and other di- and trivalent cations induced secondary structure and hydrophobic packing after partial neutralization of the highly negatively charged MIIA domain. Mass spectrometry and isothermal titration calorimetry showed two Ca2+-binding sites which promote structure formation with a total binding enthalpy of -110 kJ mol(-1) at a low micromolar K-d. Putative binding motifs were identified by sequence similarity to EF-hand domains and their structure analyzed by molecular dynamics simulations. The stoichiometric Ca2+-dependent induction of structure correlated with catalytic activity and may provide a "host-sensing" mechanism that is shared among pathogens that use a T3SS for efficient secretion of disordered proteins

Complexation of lanthanides, actinides and transition metal cations with a 6-(1,2,4-triazin-3-yl)-2,2’:6’,2’’-terpyridine ligand: implications for actinide(III) /lanthanide(III) partitioning

The quadridentate N-heterocyclic ligand 6-(5,5,8,8-tetramethyl-5,6,7,8-tetrahydro-1,2,4-benzotriazin-3-yl)-2,2’:6’,2’’-terpyridine (CyMe4-hemi-BTBP) has been synthesized and its interactions with Am(III), U(VI), Ln(III) and some transition metal cations have been evaluated by X-ray crystallographic analysis, Am(III)/Eu(III) solvent extraction experiments, UV absorption spectrophotometry, NMR studies and ESI-MS. Structures of the 1:1 complexes with Eu(III), Ce(III) and the linear uranyl (UO22+) ion were obtained by X-ray crystallographic analysis, and showed similar coordination behavior to related BTBP complexes. In methanol, the stability constants of the Ln(III) complexes are slightly lower than those of the analogous quadridentate bis-triazine BTBP ligands, while the stability constant for the Yb(III) complex is higher. 1H NMR titrations and ESI-MS with lanthanide nitrates showed that the ligand forms only 1:1 complexes with Eu(III), Ce(III) and Yb(III), while both 1:1 and 1:2 complexes were formed with La(III) and Y(III) in acetonitrile. A mixture of isomeric chiral 2:2 helical complexes was formed with Cu(I), with a slight preference (1.4:1) for a single directional isomer. In contrast, a 1:1 complex was observed with the larger Ag(I) ion. The ligand was unable to extract Am(III) or Eu(III) from nitric acid solutions into 1-octanol, except in the presence of a synergist at low acidity. The results show that the presence of two outer 1,2,4-triazine rings is required for the efficient extraction and separation of An(III) from Ln(III) by quadridentate N-donor ligand

Highly efficient separation of actinides from lanthanides by a phenanthroline-derived bis-triazine ligand

The synthesis, lanthanide complexation, and solvent ex- traction of actinide(III) and lanthanide(III) radiotracers from nitric acid solutions by a phenanthroline-derived quadridentate bis-triazine ligand are described. The ligand separates Am(III) and Cm(III) from the lanthanides with remarkably high efficiency, high selectivity, and fast extraction kinetics compared to its 2,2'-bipyridine counterpart. Structures of the 1:2 bis-complexes of the ligand with Eu(III) and Yb(III) were elucidated by X-ray crystallography and force field calculations, respec-tively. The Eu(III) bis-complex is the first 1:2 bis-complex of a quadridentate bis-triazine ligand to be characterized by crystallography. The faster rates of extraction were verified by kinetics measurements using the rotating membrane cell technique in several diluents. The improved kinetics of metal ion extraction are related to the higher surface activity of the ligand at the phase interface. The improvement in the ligand's properties on replacing the bipyridine unit with a phenanthroline unit far exceeds what was anticipated based on ligand design alone