Cellular interactions with polystyrene nanoplastics-The role of particle size and protein corona.

Plastic waste is ubiquitously spread across the world and its smaller analogs-microplastics and nanoplastics-raise particular health concerns. While biological impacts of microplastics and nanoplastics have been actively studied, the chemical and biological bases for the adverse effects are sought after. This work explores contributory factors by combining results from in vitro and model mammalian membrane experimentation to assess the outcome of cell/nanoplastic interactions in molecular detail, inspecting the individual contribution of nanoplastics and different types of protein coronae. The in vitro study showed mild cytotoxicity and cellular uptake of polystyrene (PS) nanoplastics, with no clear trend based on nanoplastic size (20 and 200 nm) or surface charge. In contrast, a nanoplastic size-dependency on bilayer disruption was observed in the model system. This suggests that membrane disruption resulting from direct interaction with PS nanoplastics has little correlation with cytotoxicity. Furthermore, the level of bilayer disruption was found to be limited to the hydrophilic headgroup, indicating that transmembrane diffusion was an unlikely pathway for cellular uptake-endocytosis is the viable mechanism. In rare cases, small PS nanoplastics (20 nm) were found in the vicinity of chromosomes without a nuclear membrane surrounding them; however, this was not observed for larger PS nanoplastics (200 nm). We hypothesize that the nanoplastics can interact with chromosomes prior to nuclear membrane formation. Overall, precoating PS particles with protein coronae reduced the cytotoxicity, irrespective of the corona type. When comparing the two types, the extent of reduction was more apparent with soft than hard corona

Outcome measures in clinical trials of treatments for acute severe haemorrhage

BACKGROUND: Acute severe haemorrhage is a common complication of injury, childbirth, surgery, gastrointestinal pathologies and other medical conditions. Bleeding is a major cause of death, but patients also die from non-bleeding causes, the frequency of which varies by the site of haemorrhage and between populations. Because patients can bleed to death within hours, established interventions inevitably take priority over randomisation into a trial. These circumstances raise challenges in selecting appropriate outcome measures for clinical trials of haemostatic interventions. MAIN BODY: We use data from three large randomised controlled trials in acute severe haemorrhage (CRASH-2, WOMAN and HALT-IT) to explore the strengths and limitations of outcome measures commonly used in trials of haemostatic treatments, including all-cause and cause-specific mortality, blood transfusion and surgical interventions. Many deaths following acute severe haemorrhage are due to patient comorbidities or complications rather than bleeding. If non-bleeding deaths are unaffected by a haemostatic intervention, even large trials will have low power to detect an effect on all-cause mortality. Due to the dilution from deaths unaffected or reduced by the trial treatment, all-cause mortality can also obscure important harmful effects. Additionally, because the relative contributions of different causes of death vary within and between patient populations, all-cause mortality is not generalisable. Different causes of death occur at different time intervals from bleeding onset, with bleeding deaths generally occurring early. Time-specific mortality can therefore be used as a proxy for cause in un-blinded trials where bias is a concern or in situations where cause of death cannot be assessed. Urgent treatment is critical, and so post-randomisation blood transfusion and surgery are often planned before or at the time of randomisation and therefore cannot be influenced by the trial treatment. CONCLUSIONS: All-cause mortality has low power, lacks generalisability and can obscure harmful effects. Cause-specific mortality, such as death due to bleeding or thrombosis, avoids these drawbacks. In certain scenarios, time-specific mortality can be used as a proxy for cause-specific mortality. Blood transfusion and surgical procedures have limited utility as outcome measures in trials of haemostatic treatments

Guidelines for the use of flow cytometry and cell sorting in immunological studies (second edition)

Note: In order to make the guidelines as beneficial as possible to the scientific community, if you wish to refer to a specific section when referring to these guidelines, please ensure to use the Chapter and Section information. For example: …as noted in section VII.11 of [1] … 1. Cossarizza, A., Chang, H. D., Radbruch, A., Acs, A., Adam, A., Adam-Klages, S., Agace, W. et al., Guidelines for the use of flow cytometry and cell sorting in immunological studies (second edition). Eur. J. Immunol. 2019. 49: 1457–1973.The final version of the second edition published by WIley-VCH is freely available online at: https://doi.org/10.1002/eji.201970107 The third edition was published online at https://doi.org/10.1002/eji.202170126 on 7 December 2021 under the terms of the Creative Commons Attribution License (https://creativecommons.org/licenses/by/4.0/), which permits use, distribution and reproduction in any medium, provided the original work is properly cited.These guidelines are a consensus work of a considerable number of members of the immunology and flow cytometry community. They provide the theory and key practical aspects of flow cytometry enabling immunologists to avoid the common errors that often undermine immunological data. Notably, there are comprehensive sections of all major immune cell types with helpful Tables detailing phenotypes in murine and human cells. The latest flow cytometry techniques and applications are also described, featuring examples of the data that can be generated and, importantly, how the data can be analysed. Furthermore, there are sections detailing tips, tricks and pitfalls to avoid, all written and peer-reviewed by leading experts in the field, making this an essential research companion.Work in the laboratory of Dieter Adam is supported by the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation)—Projektnummer 125440785 – SFB 877, Project B2. Petra Hoffmann, Andrea Hauser, and Matthias Edinger thank BD Biosciences®, San José, CA, USA, and SKAN AG, Bale, Switzerland for fruitful cooperation during the development, construction, and installation of the GMP-compliant cell sorting equipment and the Bavarian Immune Therapy Network (BayImmuNet) for financial support. Edwin van der Pol and Paola Lanuti acknowledge Aleksandra Gąsecka M.D. for excellent experimental support and Dr. Rienk Nieuwland for textual suggestions. This work was supported by the Netherlands Organisation for Scientific Research – Domain Applied and Engineering Sciences (NWO-TTW), research program VENI 15924. Jessica G Borger, Kylie M Quinn, Mairi McGrath, and Regina Stark thank Francesco Siracusa and Patrick Maschmeyer for providing data. Larissa Nogueira Almeida was supported by DFG research grant MA 2273/14-1. Rudolf A. Manz was supported by the Excellence Cluster “Inflammation at Interfaces” (EXC 306/2). Susanne Hartmann and Friederike Ebner were supported by the German Research Foundation (GRK 2046). Hans Minderman was supported by NIH R50CA211108. This work was funded by the Deutsche Forschungsgemeinschaft through the grant TRR130 (project P11 and C03) to Thomas H. Winkler. Ramon Bellmàs Sanz, Jenny Kühne, and Christine S. Falk thank Jana Keil and Kerstin Daemen for excellent technical support. The work was funded by the Germany Research Foundation CRC738/B3 (CSF). The work by the Mei laboratory was supported by German Research Foundation Grant ME 3644/5-1 and TRR130 TP24, the German Rheumatism Research Centre Berlin, European Union Innovative Medicines Initiative - Joint Undertaking - RTCure Grant Agreement 777357, the Else Kröner-Fresenius-Foundation, German Federal Ministry of Education and Research e:Med sysINFLAME Program Grant 01ZX1306B and KMU-innovativ “InnoCyt”, and the Leibniz Science Campus for Chronic Inflammation (http://www.chronische-entzuendung.org). Axel Ronald Schulz, Antonio Cosma, Sabine Baumgart, Brice Gaudilliere, Helen M. McGuire, and Henrik E. Mei thank Michael D. Leipold for critically reading the manuscript. Christian Kukat acknowledges support from the ISAC SRL Emerging Leaders program. John Trowsdale received funding from the European Research Council under the European Union's Horizon 2020 research and innovation program (Grant Agreement 695551)

Guidelines for the use of flow cytometry and cell sorting in immunological studies (second edition)

These guidelines are a consensus work of a considerable number of members of the immunology and flow cytometry community. They provide the theory and key practical aspects of flow cytometry enabling immunologists to avoid the common errors that often undermine immunological data. Notably, there are comprehensive sections of all major immune cell types with helpful Tables detailing phenotypes in murine and human cells. The latest flow cytometry techniques and applications are also described, featuring examples of the data that can be generated and, importantly, how the data can be analysed. Furthermore, there are sections detailing tips, tricks and pitfalls to avoid, all written and peer-reviewed by leading experts in the field, making this an essential research companion