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Cell-free RNA from liquid biopsies can be analyzed to determine disease tissue of origin. We extend this concept to identify cell types of origin using the Tabula Sapiens transcriptomic cell atlas as well as individual tissue transcriptomic cell atlases in combination with the Human Protein Atlas RNA consensus dataset. We define cell type signature scores, which allow the inference of cell types that contribute to cell-free RNA for a variety of diseases. Cell types affected by various diseases are inferred from cell-free RNA. [ABSTRACT FROM AUTHOR]

Vaccines against SARS-CoV-2 are urgently required, but early development of vaccines against SARS-CoV-1 resulted in enhanced disease after vaccination. Careful assessment of this phenomena is warranted for vaccine development against SARS CoV-2. Here we report detailed immune profiling after ChAdOx1 nCoV-19 (AZD1222) and subsequent high dose challenge in two animal models of SARS-CoV-2 mediated disease. We demonstrate in rhesus macaques the lung pathology caused by SARS-CoV-2 mediated pneumonia is reduced by prior vaccination with ChAdOx1 nCoV-19 which induced neutralising antibody responses after a single intramuscular administration. In a second animal model, ferrets, ChAdOx1 nCoV-19 reduced both virus shedding and lung pathology. Antibody titre were boosted by a second dose. Data from these challenge models on the absence of enhanced disease and the detailed immune profiling, support the continued clinical evaluation of ChAdOx1 nCoV-19. Lambe, Spencer, Thomas, Gilbert and colleagues report on the detailed immune profile of rhesus macaques and ferrets vaccinated against SARS-CoV-2 under high dose challenge. Their findings indicate that the ChAdOx1 nCoV-19 (AZD1222) the vaccine induces immune responses and reduces disease symptoms in both models, including SARS-CoV-2 mediated pneumonia and virus shedding. [ABSTRACT FROM AUTHOR]

Live attenuated influenza vaccine (LAIV) is widely used to protect humans from seasonal influenza infection, particularly in children. In contrast to inactivated vaccines, the LAIV can induce both mucosal and cellular immune responses. Here we show that a single dose of monovalent H1N1pdm09-specific LAIV in the ferret model is fully protective against a subsequent wild-type H1N1pdm09 challenge, and furthermore reduces the severity of disease following challenge with a different influenza A subtype (H3N2). The reduced severity comprised reductions in weight loss and fever, as well as more rapid clearance of virus, compared to non-vaccinated H3N2-challenged ferrets. No H3N2-neutralizing antibodies were detected in vaccinated ferret sera. Rather, heterosubtypic protection correlated with interferon-gamma+ (IFN-γ+) T-cell responses measured in peripheral blood and in lung lymphocytes. The IFN-γ+ cells were cross-reactive to H3N2 virus even when obtained from vaccinated animals that had never been exposed to H3N2 virus. We believe this study provides compelling evidence that the LAIV can provide a significant reduction in infection and symptoms when challenged with heterosubtypic influenza strains not included in the LAIV, highlighting the importance of cross-reactive T-cells in the design of a universal influenza vaccine. [ABSTRACT FROM AUTHOR]

A novel coronavirus, SARS-CoV-2, has been identified as the causative agent of the current COVID-19 pandemic. Animal models, and in particular non-human primates, are essential to understand the pathogenesis of emerging diseases and to assess the safety and efficacy of novel vaccines and therapeutics. Here, we show that SARS-CoV-2 replicates in the upper and lower respiratory tract and causes pulmonary lesions in both rhesus and cynomolgus macaques. Immune responses against SARS-CoV-2 are also similar in both species and equivalent to those reported in milder infections and convalescent human patients. This finding is reiterated by our transcriptional analysis of respiratory samples revealing the global response to infection. We describe a new method for lung histopathology scoring that will provide a metric to enable clearer decision making for this key endpoint. In contrast to prior publications, in which rhesus are accepted to be the preferred study species, we provide convincing evidence that both macaque species authentically represent mild to moderate forms of COVID-19 observed in the majority of the human population and both species should be used to evaluate the safety and efficacy of interventions against SARS-CoV-2. Importantly, accessing cynomolgus macaques will greatly alleviate the pressures on current rhesus stocks. Non-human primates are important animal models for studying SARS-CoV-2 infection. Here, Salguero et al. directly compare rhesus and cynomolgus macaques and show that both species represent COVID-19 disease of mild clinical cases, and provide a lung histopathology scoring system. [ABSTRACT FROM AUTHOR]

There is a vital need for authentic COVID-19 animal models to enable the pre-clinical evaluation of candidate vaccines and therapeutics. Here we report a dose titration study of SARS-CoV-2 in the ferret model. After a high (5 × 106 pfu) and medium (5 × 104 pfu) dose of virus is delivered, intranasally, viral RNA shedding in the upper respiratory tract (URT) is observed in 6/6 animals, however, only 1/6 ferrets show similar signs after low dose (5 × 102 pfu) challenge. Following sequential culls pathological signs of mild multifocal bronchopneumonia in approximately 5–15% of the lung is seen on day 3, in high and medium dosed groups. Ferrets re-challenged, after virus shedding ceased, are fully protected from acute lung pathology. The endpoints of URT viral RNA replication & distinct lung pathology are observed most consistently in the high dose group. This ferret model of SARS-CoV-2 infection presents a mild clinical disease. SARS-CoV-2 induces mild infection in ferret model. Here, Ryan et al. characterise optimal infection dosage inducing upper respiratory tract (UTR) viral shedding, progression time of viral shedding, and pathology in ferrets and finally provide evidence for protection after re-challenge. [ABSTRACT FROM AUTHOR]

Purpose: Erwinia chrysanthemi L-asparaginase (ErA) is an enzyme commonly used in the treatment regimen for Acute Lymphoblastic Leukaemia (ALL). Biopharmaceutical products such as ErA must be monitored for modifications such as deamidation, typically using ion-exchange chromatography (IEX). Analysis of clinical-grade ErA using native IEX resolves a number of enzymatically-active, acidic variants that were poorly characterised. Methods: ErA IEX variants were isolated and fully characterised using capillary electrophoresis (cIEF), LC-MS and LC-MS/MS of proteolytic digests, and structural techniques including circular dichroism, small-angle X-ray scattering (SAXS) and ion-mobility mass spectrometry (IM-MS). Results: LC-MS, MS/MS and cIEF demonstrated that all ErA isolates consist mainly of enzyme lacking primary-sequence modifications (such as deamidation). Both SAXS and IM-MS revealed a different conformational state in the most prominent acidic IEX peak. However, SAXS data also suggested conformational differences between the main peak and major acidic variant were minor, based on comparisons with crystal structures. Conclusions: IEX data for biopharmaceuticals such as ErA should be thoroughly characterised, as the most common modifications, such as deamidation, may be absent. [ABSTRACT FROM AUTHOR]

Reoperative surgery for the morbidly obese has become increasingly common due to postoperative weight regain. There are limited studies evaluating the effectiveness of revisional surgery. This study evaluates the weight loss outcomes of revisional surgery over a 2-year period at our University Hospital, USA. Of the 412 patients who underwent laparoscopic bariatric surgery between June 2009 and June 2011, we identified 25 patients who had Roux-en-Y gastric bypass (RYGB) originally, who underwent laparoscopic revisional surgery for weight regain. Preoperative and postoperative data were reviewed. Statistical analysis was performed using paired t test. This study includes 0 male and 25 female patients with an average age of 42 (range min to max: 28-58), mean original body mass index (BMI) of 54.6 kg/m ( r = 37.3-80.7), average lowest BMI achieved of 32.2 ( r = 20.1-50.9), and average BMI at the time of revision of 41.0 kg/m ( r = 29.5-60.7, standard deviation (SD) = 8.5). All laparoscopic revisions consisted of resizing the gastric pouch by resection and recreating the gastrojejunostomy. Average hospital length of stay was 1.28 days ( r = 1-4). Perioperative morbidity was 8 %; one patient developed a trocar site hernia which required repair, and another suffered postoperative bleeding requiring transfusion. There was no mortality. Postoperative BMI averages at 3, 6, 9, 12, and 24 months were 35.0 (SD = 7.15), 34.7 (SD = 4.26), 36.2 (SD = 7.63), 33.0 (SD = 6.58), and 44.2 (SD = 12.87), respectively. Statistically significant weight loss was achieved at 3 [t (10) = 6.74, p < 0.05], 6 [t (7) = 4.69, p < 0.05], 9 [t (9) = 2.94, p < 0.05], and 12 [t (6) = 3.78, p < 0.05] months. However, there was no statistically significant weight loss at 24 months postoperatively [t (4) = −0.16, p > 0.05]. Laparoscopic revisional bariatric surgery can be performed with significant weight loss up to 1 year postoperatively. However, additional studies are required to evaluate longer-term success. [ABSTRACT FROM AUTHOR]

PET imaging has been recently introduced for investigating the type 1 angiotensin II receptor (AT1R) in vivo . The goal of the present study was to investigate the effects of acute and chronic exposure to angiotensin converting enzyme inhibitors (ACEI) on the AT1R in the dog kidney. Animals were imaged at baseline, after acute intravenous ACEI treatment and after a chronic 2-week exposure to an oral ACEI. Control animals were imaged at identical time points in the absence of ACEI treatment. In vivo AT1R binding expressed by K i was increased in the renal cortex by chronic ACEI treatment ( p < 0.05). In vitro measurements of AT1R density ( B max) also revealed significant increases in AT1R in isolated glomeruli ( p < 0.05). Plasma renin activity was increased, but angiotensin II (Ang II) and the Ang II/Ang I ratio showed a weak correlation with chronic ACEI treatment, consistent with an Ang II escape phenomenon. This study reveals, for the first time, that chronic ACEI treatment increases AT1R binding in vivo in the dog renal cortex. [ABSTRACT FROM AUTHOR]

Miller Dieker syndrome (MDS, type I lissencephaly) is a neuronal migration disorder, which is caused by deletions along the short arm of chromosome 17 (17p13.3). Recent studies would suggest that the cortical lamination in MDS is inverted, based on morphological criteria. The present neuropathological study examines the cerebral cortex from a 33-week old fetus with MDS using both neuronal and laminar-specific markers. These expression studies demonstrate a relatively preserved cortex and cortical lamination, overlying a layer of immature neurons in MDS brain. The findings are consistent with both a migratory and proliferative defect, giving rise to lissencephaly. Moreover, characterization of such rare human malformations of cortical development by immunohistochemical techniques will provide a greater understanding of the underlying mechanisms. [ABSTRACT FROM AUTHOR]

An effective universal vaccine for influenza will likely need to induce virus-specific T-cells, which are the major mediator of heterosubtypic cross-protection between different subtypes of influenza A virus. In this study we characterise the cell-mediated immune response in ferrets during heterosubtypic protection induced by low-dose H1N1 virus infection against an H3N2 virus challenge, given 4 weeks later. Although the ferrets were not protected against the infection by H3N2 virus, the duration of virus shedding was shortened, and clinical disease was markedly reduced. No cross-reactive neutralizing antibodies were detected, but cross-reactive interferon-gamma-secreting T cells were detected in the circulation prior to H3N2 challenge. These T-cells peaked at 11 days post-H1N1 infection, and were strongly induced in blood and in lung following H3N2 infection. The rapid induction of interferon-gamma-secreting cells in ferrets previously infected with H1N1 virus, but not in naïve ferrets, suggests induction of memory T-cells. These results are in accord with the observations that pre-existing cross-reactive T-cells correlate with protection in humans and have implications for outbreak modelling and universal vaccine design. [ABSTRACT FROM AUTHOR]

Off-lattice models are a well-established approach in multicellular modeling, where cells are represented as points that are free to move in space. The representation of cells as point objects is useful in a wide range of settings, particularly when large populations are involved; however, a purely point-based representation is not naturally equipped to deal with objects that have length, such as cell boundaries or external membranes. Here we introduce an off-lattice modeling framework that exploits rigid body mechanics to represent objects using a collection of conjoined one-dimensional edges in a viscosity-dominated system. This framework can be used to represent cells as free moving polygons, to allow epithelial layers to smoothly interact with themselves, to model rod-shaped cells such as bacteria and to robustly represent membranes. We demonstrate that this approach offers solutions to the problems that limit the scope of current off-lattice multicellular models., (© 2021. The Author(s), under exclusive licence to Springer Nature America, Inc.)