Multiphase Stirred Tank Bioreactors – New Geometrical Concepts and Scale‐up Approaches

Mainly with respect to biotechnological cases, current developments in the field of impeller geometries and findings for multistage configurations with a specific view on aerated stirred tanks are reviewed. Although often the first choice, in the given case the 6‐straight blade disc turbine is usually not the best option. Furthermore, quantities usable for scale‐up, specifically applicable in this field are discussed. Only quantities taking local conditions into account appear to be able to actually compare different stirrer types and scales.DFG, 56091768, TRR 63: Integrierte chemische Prozesse in flüssigen MehrphasensystemenDFG, 315464571, Interaktion der mechanischen Beanspruchung und der Produktivität von biologischen Agglomeraten in RührfermenternDFG, 256647858, Stoffübergang von aufsteigenden Blasen in reagierenden FlüssigphasenTU Berlin, Open-Access-Mittel - 201

Influence of different silica nanoparticles on drop size distributions in agitated liquid‐liquid systems

The impact of different silica nanoparticles on rheology, interfacial tension and drop size distributions in liquid‐liquid systems is determined experimentally. The particles vary in wettability and specific surface area. In contrast to commonly used high‐energy devices for Pickering emulsion preparation, low energy input by stirring allows to quantify drop breakage and coalescence in steady state and dynamic conditions. The experiments can provide essential information for drop size model development in nanoparticle‐stabilized emulsions.DFG, 56091768, TRR 63: Integrierte chemische Prozesse in flüssigen MehrphasensystemenTU Berlin, Open-Access-Mittel - 201

Live Imaging of Antifungal Activity by Human Primary Neutrophils and Monocytes in Response to A. fumigatus

This work has been supported by the MRC and the University of Aberdeen (MRC Centre for Medical Mycology) and by the Wellcome Trust Strategic Award - Medical Mycology Fungal Immunology (SFB, JMB, JK, AW). A special thank you is given to the support from the Chloe fund. TMH is supported by a grant from the National institute of health (NIH, code RO1 093808) and the Memorial Sloan Kettering Cancer Center is supported by NIH grant P30 CA008748. Additionally, TMH is an investigator in the Pathogenesis of Infectious Disease supported by the Burroughs Wellcome Fund. We wish to thank the Aberdeen Microscopy and Histology Facility for their help and support.Peer reviewedPublisher PD

HLA Ligand Atlas: a benign reference of HLA-presented peptides to improve T-cell-based cancer immunotherapy

BACKGROUND The human leucocyte antigen (HLA) complex controls adaptive immunity by presenting defined fractions of the intracellular and extracellular protein content to immune cells. Understanding the benign HLA ligand repertoire is a prerequisite to define safe T-cell-based immunotherapies against cancer. Due to the poor availability of benign tissues, if available, normal tissue adjacent to the tumor has been used as a benign surrogate when defining tumor-associated antigens. However, this comparison has proven to be insufficient and even resulted in lethal outcomes. In order to match the tumor immunopeptidome with an equivalent counterpart, we created the HLA Ligand Atlas, the first extensive collection of paired HLA-I and HLA-II immunopeptidomes from 227 benign human tissue samples. This dataset facilitates a balanced comparison between tumor and benign tissues on HLA ligand level. METHODS Human tissue samples were obtained from 16 subjects at autopsy, five thymus samples and two ovary samples originating from living donors. HLA ligands were isolated via immunoaffinity purification and analyzed in over 1200 liquid chromatography mass spectrometry runs. Experimentally and computationally reproducible protocols were employed for data acquisition and processing. RESULTS The initial release covers 51 HLA-I and 86 HLA-II allotypes presenting 90,428 HLA-I- and 142,625 HLA-II ligands. The HLA allotypes are representative for the world population. We observe that immunopeptidomes differ considerably between tissues and individuals on source protein and HLA-ligand level. Moreover, we discover 1407 HLA-I ligands from non-canonical genomic regions. Such peptides were previously described in tumors, peripheral blood mononuclear cells (PBMCs), healthy lung tissues and cell lines. In a case study in glioblastoma, we show that potential on-target off-tumor adverse events in immunotherapy can be avoided by comparing tumor immunopeptidomes to the provided multi-tissue reference. CONCLUSION Given that T-cell-based immunotherapies, such as CAR-T cells, affinity-enhanced T cell transfer, cancer vaccines and immune checkpoint inhibition, have significant side effects, the HLA Ligand Atlas is the first step toward defining tumor-associated targets with an improved safety profile. The resource provides insights into basic and applied immune-associated questions in the context of cancer immunotherapy, infection, transplantation, allergy and autoimmunity. It is publicly available and can be browsed in an easy-to-use web interface at https://hla-ligand-atlas.org

Galaxy bulges and their massive black holes: a review

With references to both key and oft-forgotten pioneering works, this article starts by presenting a review into how we came to believe in the existence of massive black holes at the centres of galaxies. It then presents the historical development of the near-linear (black hole)-(host spheroid) mass relation, before explaining why this has recently been dramatically revised. Past disagreement over the slope of the (black hole)-(velocity dispersion) relation is also explained, and the discovery of sub-structure within the (black hole)-(velocity dispersion) diagram is discussed. As the search for the fundamental connection between massive black holes and their host galaxies continues, the competing array of additional black hole mass scaling relations for samples of predominantly inactive galaxies are presented.Comment: Invited (15 Feb. 2014) review article (submitted 16 Nov. 2014). 590 references, 9 figures, 25 pages in emulateApJ format. To appear in "Galactic Bulges", E. Laurikainen, R.F. Peletier, and D.A. Gadotti (eds.), Springer Publishin

Dispersion und Phasentrennung in flüssigen Mehrphasensystemen : Einfluss dreiphasiger Dispersionen auf Tropfengrößenverteilungen

Microemulsion systems consisting of water, 1-dodecene and different non-ionic surfactants can develop up to three liquid phases as a function of composition and process conditions. These innovative solvent systems are promising reaction media for processes such as the hydroformylation of long-chained olefins. In this work, the influence of the third phase on the drop size distributions and the phase separation behavior was investigated since these are crucial parameters to achieve high reaction rates and an efficient catalyst recycling. A methodology to identify the phases in agitated systems was developed using an in-situ endoscope technique. By analyzing phase behavior and physical properties of the systems in combination with drop size analysis, the influencing factors on the drop size distributions under two and especially three phase conditions were quantified. The prediction of the droplet sizes in three phase systems with population balance equations is a challenging task that mainly works for simple dispersion conditions and in a narrow process condition range. Although the predictive power is not yet satisfactory, this work provides an overview on how a change in process conditions affects all parameters relevant for drop breakage and coalescence. Furthermore, the impact of the dispersion conditions on the phase separation was investigated for two phase systems, simple three phase systems and also for the case of multiple emulsions. Experimental and simulation results indicate, that the phase separation process can be modelled under two phase and three phase conditions.Mikroemulsionssysteme bestehend aus Wasser, 1-Dodecen und nicht-ionischen Tensiden bilden je nach Zusammensetzung und Prozessbedingungen bis zu drei flüssige Phasen aus. Da diese Systeme vielversprechende Reaktionsmedien für die Hydroformylierung langkettiger Olefine und vergleichbare Prozesse sind, wurde der Einfluss der dritten Phase auf Dispersion und Phasentrennung untersucht. Beide Phänomene sind entscheidend für den Gesamtprozess, da sie sowohl die Reaktionsraten als auch die Effizienz des Katalysatorrecyclings und die Reinheit des Reaktionsproduktes beeinflussen. Mittels einer in-situ Endoskopmesstechnik und Bildanalyse wurde in dieser Arbeit eine Methode entwickelt, um die flüssigen Phasen in geführten Systemen zu identifizieren. Durch eine Kombination dieser Methodik mit einer Analyse des Phasenverhaltens und der physikalischen Eigenschaften wurden des Weiteren relevante Einflussgrößen auf Tropfenbruch und Koaleszenz unter zwei- und insbesondere dreiphasigen Bedingungen bestimmt. Die Vorhersage von Tropfengrößen mittels Populationsbilanzen verläuft erfolgreich in zweiphasigen Mikroemulsionssystemen, jedoch ist die Vorhersagekraft unter dreiphasigen Bedingungen nur in eingeschränkten Prozessparametern sowie in vergleichbar einfachen Systemen ausreichend. Um eine weitere Optimierung der Vorhersage zu ermöglichen wurden unter anderem Bedingungen für die Bildung multipler Emulsionen sowieso zu erwartende Trends der Tropfengrößen als Funktion der Prozessbedingungen dargestellt. Darüber hinaus konnte der Einfluss der dreiphasigen Dispersionen auf die Phasentrennung aufgeklärt und quantifiziert werden. Dazu wurde ein bestehendes Modell zur Phasentrennung auf den dreiphasigen Zustand erweitert. Ein Vergleich der Experimente und Simulationen zeigt ein hohes Potenzial dieses Modells für die Beschreibung dreiphasiger flüssig/flüssig-Systeme.DFG, TRR 63, Integrierte chemische Prozesse in flüssigen Mehrphasensysteme

Inflammatory monocytes are detrimental to the host immune response during acute infection with Cryptococcus neoformans.

Cryptococcus neoformans is a leading cause of invasive fungal infections among immunocompromised patients. However, the cellular constituents of the innate immune response that promote clearance versus progression of infection upon respiratory acquisition of C. neoformans remain poorly defined. In this study, we found that during acute C. neoformans infection, CCR2+ Ly6Chi inflammatory monocytes (IM) rapidly infiltrate the lungs and mediate fungal trafficking to lung-draining lymph nodes. Interestingly, this influx of IM is detrimental to the host, since ablating IM or impairing their recruitment to the lungs improves murine survival and reduces fungal proliferation and dissemination. Using a novel conditional gene deletion strategy, we determined that MHC class II expression by IM did not mediate their deleterious impact on the host. Furthermore, although ablation of IM reduced the number of lymphocytes, innate lymphoid cells, and eosinophils in the lungs, the effects of IM were not dependent on these cells. We ascertained that IM in the lungs upregulated transcripts associated with alternatively activated (M2) macrophages in response to C. neoformans, consistent with the model that IM assume a cellular phenotype that is permissive for fungal growth. We also determined that conditional knockout of the prototypical M2 marker arginase 1 in IM and deletion of the M2-associated transcription factor STAT6 were not sufficient to reverse the harmful effects of IM. Overall, our findings indicate that C. neoformans can subvert the fungicidal potential of IM to enable the progression of infection through a mechanism that is not dependent on lymphocyte priming, eosinophil recruitment, or downstream M2 macrophage polarization pathways. These results give us new insight into the plasticity of IM function during fungal infections and the level of control that C. neoformans can exert on host immune responses

Deploying FLAREs to Visualize Functional Outcomes of Host-Pathogen Encounters.

One of the most exciting features of fluorescent probes is their rapid evolution from simple tracers to functional indicators in diverse research fields [1]. In mammalian cells, fluorescence has been coupled to synaptic transmission [2,3], neuronal differentiation [4], apoptotic cell death [5], fate mapping in different immune cells [6,7], and functional changes in cell physiol-ogy, for example, the induction of cytokines [8]. In microbial cells, fluorescence has long been utilized as a tracer for pathogenic microbes, revealing microbial localization, residence, and spread in host tissues [9]. However, measuring functional outcomes during individual encoun-ters with host immune cells remains challenging. In this Pearl, we describe fluorescence-based approaches, which we term “functional micro-bial reporters, ” designed to relay changes in microbial physiology that occur in host cell and tis-sue environments. This class of microbial reporters typically harnesses fluorescence emission at two wavelengths. One of these signals functions as an invariant tracer of microbial cells and is generally unaffected by hostile conditions that are encountered during interactions with host cells, such as reactive oxygen species or acidified compartments. The other signal varies accord-ing to a change in microbial physiology or residence in the host. This second signal may act as