Improving the productivity and product quality of antibodies expressed from a CHO transient system

Transient transfection of CHO cells is a widely used tool to express recombinant proteins for non-GLP preclinical studies due to the system’s ability to rapidly produce proteins of similar product quality to CHO stable cell lines. Our high throughput CHO transient transfection process allows for efficient generation of milligram to multi-gram amounts of protein from small scale automated 96-deep well plates and tubespins to large scale 100L bioreactors. In this work, we present a case study describing the influence of media components on PEI-mediated CHO transfections. Given the dependence of PEI transfection on electrostatic interactions for formation and cell internalization of PEI:DNA complexes, the basal media composition significantly affects transfection productivity. We found that while higher iron levels in the basal media inhibited transfection titers, copper and zinc had minimal impact. As transfection efficiency is more sensitive to changes in basal media composition, we explored altering the batch feed composition for further process improvements. The addition of DMSO to the batch feed further increased productivity. Supplementing the feed with carnosine, an antioxidant and metal ion chelator, reduced huIgG1 afucosylation levels. This addition allowed us to achieve a comparable range of afucosylated antibody to our stable CHO cell lines. Our data demonstrates that modifying production and feed medium components in our CHO transfection process can provide benefits towards increasing yields and modulating product quality

Essential Newborn Care during Humanitarian Crises: Integration of Low-Cost Interventions

Newborn healthcare has long been neglected on the international agenda despite neonatal death making up 44% of all under-five deaths. Neonates are newborns under 28 days of age and are the most vulnerable population with the highest risk of mortality during humanitarian emergencies. The common misconception that neonatal healthcare is very expensive and requires delivery from highly skilled healthcare professionals must be dismissed. There are many low-cost interventions that are highly effective at saving lives, the most notable ones being kangaroo mother care, bag and mask resuscitation, and basic immunizations. The leading causes of neonatal death are prematurity, intrapartum complications, and infections including sepsis. Despite the extensive and high-quality manuals available from accredited international humanitarian health organizations, many challenges remain in the implementation of these guidelines by healthcare workers on the field. The most commonly cited problems include lack of funding and poor human resources. In order to achieve SDG goals of reduction in maternal and neonatal mortality rates, the global community must work together to scale-up neonatal interventions addressing small and ill newborns as well as improve training of healthcare workers concerning newborn care

Culture conditions for optimal growth of actinomycetes from marine sponges

Actinomycetes are filamentous gram-positive bacteria that can be found abundantly in both terrestrial and marine environment. These bacteria are known as producers of many bioactive compounds through the production of secondary metabolites for their survival and adaptation in nature and have been widely used today as therapeutic agents. Marine actinomycetes have been the focus of researc over the past decade for new drugs discovery due to its unique adaptation in the harsh sea environment. It is believed that marine actinomycetes could produce compounds that are rare and unique compared to the terrestrial actinomycetes. Despite its potential, marine actinomycetes are critically difficult to culture in laboratory because these actinomycetes live in extreme environment in the sea with high salt concentration, high pressure, low temperature, and constant pH changes of seawater in its natural environment. Hence, in this study, optimum condition to culture marine actinomycetes was achieved by culturing the marine actinomycetes from marine sponges on different culture condition such as different types of isolation media, pH, seasalt concentration, temperature, and incubation time. Starch casein agar (SCA) is shown to be the best isolation media compared to actinomycetes isolation agar (AIA) and Kuster agar (KUA). The growth of marine actinomycetes is optimum at pH 7, 40 % of seasalt concentration, 20–30 °C and 7–10 days of incubation time

Inhibition of IFN-γ Signaling by an Epstein-Barr Virus Immediate-Early Protein

AbstractViruses have evolved elaborate mechanisms to target many aspects of the host's immune response. The cytokine IFN-γ plays a central role in resistance of the host to infection via direct antiviral effects as well as modulation of the immune response. In this study, we demonstrate that the Epstein-Barr virus (EBV) immediate-early protein, BZLF1, inhibits the IFN-γ signaling pathway. BZLF1 decreases the ability of IFN-γ to activate a variety of important downstream target genes, such as IRF-1, p48, and CIITA, and prevents IFN-γ-induced class II MHC surface expression. Additionally, BZLF1 inhibits IFN-γ-induced STAT1 tyrosine phosphorylation and nuclear translocation. Finally, we demonstrate that BZLF1 decreases expression of the IFN-γ receptor, suggesting a mechanism by which EBV may escape antiviral immune responses during primary infection

Generation and Characterisation of a Pax8-CreERT2 Transgenic Line and a Slc22a6-CreERT2 Knock-In Line for Inducible and Specific Genetic Manipulation of Renal Tubular Epithelial Cells.

Genetically relevant mouse models need to recapitulate the hallmarks of human disease by permitting spatiotemporal gene targeting. This is especially important for replicating the biology of complex diseases like cancer, where genetic events occur in a sporadic fashion within developed somatic tissues. Though a number of renal tubule targeting mouse lines have been developed their utility for the study of renal disease is limited by lack of inducibility and specificity. In this study we describe the generation and characterisation of two novel mouse lines directing CreERT2 expression to renal tubular epithelia. The Pax8-CreERT2 transgenic line uses the mouse Pax8 promoter to direct expression of CreERT2 to all renal tubular compartments (proximal and distal tubules as well as collecting ducts) whilst the Slc22a6-CreERT2 knock-in line utilises the endogenous mouse Slc22a6 locus to specifically target the epithelium of proximal renal tubules. Both lines show high organ and tissue specificity with no extrarenal activity detected. To establish the utility of these lines for the study of renal cancer biology, Pax8-CreERT2 and Slc22a6-CreERT2 mice were crossed to conditional Vhl knockout mice to induce long-term renal tubule specific Vhl deletion. These models exhibited renal specific activation of the hypoxia inducible factor pathway (a VHL target). Our results establish Pax8-CreERT2 and Slc22a6-CreERT2 mice as valuable tools for the investigation and modelling of complex renal biology and disease.This work was supported by a Cancer Research UK Clinician Scientist Fellowship award (C37839/A12177) to AM. DA, BF, FY are funded by the Wellcome Trust Sanger Institute (grant number WT098051).This is the final version of the article. It first appeared from the Public Library of Science (PLOS) via https://doi.org/10.1371/journal.pone.014805

A territory-wide Study of arrhythmogenic right ventricular cardiomyopathy patients from Hong Kong

Background: Arrhythmogenic right ventricular cardiomyopathy/dysplasia (ARVC/D) is a hereditary disease characterized by fibrofatty infiltration of the right ventricular myocardium that predisposes affected patients to malignant ventricular arrhythmias, dual-chamber cardiac failure and sudden cardiac death (SCD). The present study aims to investigate the risk of detrimental cardiovascular events in an Asian population of ARVC/D patients, including the incidence of malignant ventricular arrhythmias, new-onset heart failure with reduced ejection fraction (HFrEF), as well as long-term mortality. Methods and Results: This was a territory-wide retrospective cohort study of patients diagnosed with ARVC/D between 1997 and 2019 in Hong Kong. This study consisted of 109 ARVC/D patients (median age: 61 [46–71] years; 58% male). Of these, 51 and 24 patients developed incident VT/VF and new-onset HFrEF, respectively. Five patients underwent cardiac transplantation, and 14 died during follow-up. Multivariate Cox regression identified prolonged QRS duration as a predictor of VT/VF (p <0.05). Female gender, prolonged QTc duration, the presence of epsilon waves and T-wave inversion (TWI) in any lead except aVR/V1 predicted new-onset HFrEF (p <0.05). The presence of epsilon waves, in addition to the parameters of prolonged QRS duration and worsening ejection fraction predicted all-cause mortality (p <0.05). Clinical scores were developed to predict incident VT/VF, new-onset HFrEF and all-cause mortality, and all were significantly improved by machine learning techniques. Conclusions: Clinical and electrocardiographic parameters are important for assessing prognosis in ARVC/D patients and should in turn be used in tandem to aid risk stratification in the hospital setting

Socioeconomic differences in help seeking for colorectal cancer symptoms during COVID-19: a UK-wide qualitative interview study of patient experiences in primary care

BACKGROUND: COVID-19 has led to rapid changes in healthcare delivery, raising concern that these changes may exacerbate existing inequalities in patient outcomes. AIM: To understand how patients' help-seeking experiences in primary care for colorectal cancer symptoms during COVID-19 were affected by their socioeconomic status (SES). DESIGN AND SETTING: Qualitative semi-structured interviews with males and females across the UK, recruited using purposive sampling by SES. METHOD: Interviews were carried out with 39 participants (20 higher SES; 19 lower SES) who contacted primary care about possible symptoms of colorectal cancer during COVID-19. Data were analysed using framework analysis followed by comparative thematic analysis to explore differences between groups. RESULTS: Three themes were identified with differences between SES groups: 1) how people decided to seek medical help through appraisal of symptoms; 2) how people navigated services; and 3) impact of COVID-19 on how patients interacted with healthcare professionals. The lower SES group expressed uncertainty appraising symptoms and navigating services (in terms of new processes resulting from COVID-19 and worries about infection). There was also potential for increased disparity in diagnosis and management, with other methods of getting in touch (for example, email or 111) taken up more readily by higher SES patients. CONCLUSION: The findings suggest that COVID-19 exacerbated disparities between higher and lower SES participants. This study raises awareness around challenges in help seeking in the context of the pandemic, which are likely to persist (post-COVID-19) as healthcare systems settle on new models of care (for example, digital). Recommendations are provided to reduce inequalities of care

ADAM17 substrate release in proximal tubule drives kidney fibrosis

Kidney fibrosis following kidney injury is an unresolved health problem and causes significant morbidity and mortality worldwide. In a study into its molecular mechanism, we identified essential causative features. Acute or chronic kidney injury causes sustained elevation of a disintegrin and metalloprotease 17 (ADAM17); of its cleavage-activated proligand substrates, in particular of pro-TNFα and the EGFR ligand amphiregulin (pro-AREG); and of the substrates\u27 receptors. As a consequence, EGFR is persistently activated and triggers the synthesis and release of proinflammatory and profibrotic factors, resulting in macrophage/neutrophil ingress and fibrosis. ADAM17 hypomorphic mice, specific ADAM17 inhibitor-treated WT mice, or mice with inducible KO of ADAM17 in proximal tubule (Slc34a1-Cre) were significantly protected against these effects. In vitro, in proximal tubule cells, we show that AREG has unique profibrotic actions that are potentiated by TNFα-induced AREG cleavage. In vivo, in acute kidney injury (AKI) and chronic kidney disease (CKD, fibrosis) patients, soluble AREG is indeed highly upregulated in human urine, and both ADAM17 and AREG expression show strong positive correlation with fibrosis markers in related kidney biopsies. Our results indicate that targeting of the ADAM17 pathway represents a therapeutic target for human kidney fibrosis

Healthcare Professional and Patient Perceptions of Changes in Colorectal Cancer Care Delivery During the COVID-19 Pandemic and Impact on Health Inequalities

BACKGROUND: The COVID-19 pandemic changed the way in which people were diagnosed and treated for cancer. We explored healthcare professional and patient perceptions of the main changes to colorectal cancer delivery during the COVID-19 pandemic and how they impacted on socioeconomic inequalities in care. METHODS: In 2020, using a qualitative approach, we interviewed patients (n = 15) who accessed primary care with colorectal cancer symptoms and were referred for further investigations. In 2021, we interviewed a wide range of healthcare professionals (n = 30) across the cancer care pathway and gathered national and local documents/guidelines regarding changes in colorectal cancer care. RESULTS: Changes with the potential to exacerbate inequalities in care, included: the move to remote consultations; changes in symptomatic triage, new COVID testing procedures/ways to access healthcare, changes in visitor policies and treatment (e.g., shorter course radiotherapy). Changes that improved patient access/convenience or the diagnostic process have the potential to reduce inequalities in care. DISCUSSION: Changes in healthcare delivery during the COVID-19 pandemic have the ongoing potential to exacerbate existing health inequalities due to changes in how patients are triaged, changes to diagnostic and disease management processes, reduced social support available to patients and potential over-reliance on digital first approaches. We provide several recommendations to help mitigate these harms, whilst harnessing the gains