To meet product quality and cost parameters for therapeutic monoclonal antibody (mAb) production, cell lines are required to have excellent growth, stability, and productivity characteristics. In particular, cell line generation stability is critical to the success of a program, especially where high cell line generation numbers are required for large in-market supply. However, a typical process for developing such cell lines is laborious, lengthy, and costly. In this study, we applied a FLP/FRT recombinase-mediated cassette exchange (RMCE) system to build a site-specific integration (SSI) system for mAb expression in the commercially relevant CHOK1SV cell line. Using a vector with a FRT-flanked mAb expression cassette, we generated a clonal cell line with good productivity, long-term production stability, and low mAb gene-copy number indicating the vector was located in a 'hot-spot.' A SSI host cell line was made by removing the mAb genes from the 'hot-spot' by RMCE, creating a 'landing pad' containing two recombination cassettes that allow targeting of one or two copies of recombinant genes. Cell lines made from this host exhibited excellent growth and productivity profiles, and stability for at least 100 generations in the absence of selection agents. Importantly, while clones containing two copies had higher productivity than single copy clones, both were stable over many generations. Taken together, this study suggests the use of FLP-based RMCE to develop SSI host cells for mAb production in CHOK1SV offers significant savings in both resources and overall cell line development time, leading to a shortened 'time-to-clinic' for therapeutic mAbs.

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Abstract-d Caves on other planetary bodies offer sheltered habitat for future human explorers and numerous clues to a planet's past for scientists. While recent orbital imagery provides exciting new details about cave entrances on the Moon and Mars, the interiors of these caves are still unknown and not observable from orbit. Multi-robot teams offer unique solutions for exploration and modeling subsurface voids during precursor missions. Robot teams that are diverse in terms of size, mobility, sensing, and capability can provide great advantages, but this diversity, coupled with inherently distinct low-level behavior architectures, makes coordination a challenge. This paper presents a framework that consists of an autonomous frontier and capability-based task generator, a distributed market-based strategy for coordinating and allocating tasks to the different team members, and a communication paradigm for seamless interaction between the different robots in the system. Robots have different sensors, (in the representative robot team used for testing: 2D mapping sensors, 3D modeling sensors, or no exteroceptive sensors), and varying levels of mobility. Tasks are generated to explore, model, and take science samples. Based on an individual robot's capability and associated cost for executing a generated task, a robot is autonomously selected for task execution. The robots create coarse online maps and store collected data for high resolution offline modeling. The coordination approach has been field tested at a mock cave site with highly-unstructured natural terrain, as well as an outdoor patio area. Initial results are promising for applicability of the proposed multi-robot framework to exploration and modeling of planetary caves.

The timing and concentration of oxygen supply to wort are of particular relevance in industrial beer brewing where tank volumes exceed brewhouse capacity, thereby necessitating fermenter filling in a multiple-brew fashion. A simple technique for accurately controlling dissolved oxygen concentration is presented to model industrial, multi-brew fermentations at bench and pilot scales. This method was employed to identify an effective oxygen supply strategy for batch fermentations conducted with very-high-gravity (VHG) wort. Addition of 25 ppm dissolved oxygen to the fermenting wort, 12 h after inoculation, was the most effective oxygenation strategy and reduced fermentation time by 33% compared to the control conditions. Pilotscale trials were subsequently conducted to further optimize VHG batch fermentation performance through simultaneous manipulation of key fermentation process parameters, including increased yeast inoculum size, early and increased free-rise timing and temperature, and optimized oxygenation strategy. This approach reduced the time to achieve end of fermentation targets by 34% compared to trials conducted under control conditions. The improved fermentation profile was consistent over three successive inoculations and minimal impact was observed on key flavour volatiles. Employing the optimized process for VHG batch beer production would be industrially desirable due to the potential for improved process efficiency and cost-savings.

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