Use of serum-free media for peripheral blood mononuclear cell culture and the impact on T and B cell readouts.

Introduction: As part of a wider programme of work developing next-generation risk assessment approaches (NGRA) using non-animal methods (NAMs) for safety assessment of materials, Unilever SEAC is exploring the use of a peripheral blood mononuclear cell (PBMC) system to investigate how cells from different arms of the human immune system are impacted by different treatments. To maximise human relevance, the cell cultures are supported by human serum, but this came with some challenges, including an inability to measure induced levels of immunoglobulins due to high background levels. Therefore, a study comparing use of human sera containing media with three different chemically defined serum-free media was undertaken.

Qualitative exploration of the barriers and facilitators to community pharmacy PrEP delivery for UK pharmacists and underserved community members using the COM-B model of behaviour change.

Objectives: Expanding delivery of oral pre-exposure prophylaxis (PrEP) to community pharmacies could improve access, aligning well with the UK government's goals to eliminate new HIV acquisitions by 2030. Using the Capability, Opportunity, Motivation, Behaviour (COM-B) model for behaviour change, the aim of this research was to explore the barriers and facilitators of community pharmacy PrEP delivery, for pharmacists and community members.

Methods: Community members at elevated risk of acquiring HIV and community pharmacists were recruited to participate in semi-structured interviews.

A novel approach for the synthesis of the cyclic lipopeptide globomycin.

Cyclic lipopeptides (CLiPs) are a highly diverse class of secondary metabolites produced by bacteria and fungi. Examples of CLiPs have been found that possess potent antimicrobial activity against multidrug-resistant Gram-negative bacteria. Globomycin is a 19-membered CLiP that kills both Gram-positive and Gram-negative bacteria through inhibition of lipoprotein signal peptidase II (Lsp).

Microbiome-derived antimicrobial peptides show therapeutic activity against the critically important priority pathogen, Acinetobacter baumannii.

Acinetobacter baumannii is designated by the World Health Organisation as a critical priority pathogen. Previously we discovered antimicrobial peptides (AMPs), namely Lynronne-1, -2 and -3, with efficacy against bacterial pathogens, such as Staphylococcus aureus and Pseudomonas aeruginosa. Here we assessed Lynronne-1, -2 and -3 structure by circular dichroism and efficacy against clinical strains of A.

A classic antibiotic reimagined: Rationally designed bacitracin variants exhibit potent activity against vancomycin-resistant pathogens.

Bacitracin is a macrocyclic peptide antibiotic that is widely used as a topical treatment for infections caused by gram-positive bacteria. Mechanistically, bacitracin targets bacteria by specifically binding to the phospholipid undecaprenyl pyrophosphate (CPP), which plays a key role in the bacterial lipid II cycle. Recent crystallographic studies have shown that when bound to CPP, bacitracin adopts a highly ordered amphipathic conformation.

Exploring the psychosocial burden of foot complications in diabetes: A cross-sectional survey and qualitative interview study in a United Kingdom coastal community.

Background: Foot complications in diabetes are common and destructive, resulting in substantial healthcare costs and high rates of morbidity. Coastal areas have a significantly higher burden of disease. People with diabetes experience disproportionately high rates of psychological health issues, including anxiety, depression and diabetes distress.

Host defence peptide plectasin targets bacterial cell wall precursor lipid II by a calcium-sensitive supramolecular mechanism.

Antimicrobial resistance is a leading cause of mortality, calling for the development of new antibiotics. The fungal antibiotic plectasin is a eukaryotic host defence peptide that blocks bacterial cell wall synthesis. Here, using a combination of solid-state nuclear magnetic resonance, atomic force microscopy and activity assays, we show that plectasin uses a calcium-sensitive supramolecular killing mechanism.

Impact of a varied set of stimuli on a suite of immunological parameters within peripheral blood mononuclear cells: toward a non-animal approach for assessing immune modulation by materials intended for human use.

In toxicology, steps are being taken towards more mechanism-focused and human relevant approaches to risk assessment, requiring new approaches and methods. Additionally, there is increasing emphasis by regulators on risk assessment of immunotoxicity. Here we present data from a peripheral blood mononuclear cell (PBMC) system whereby a varied set of stimuli, including those against the TCR and Toll-like receptors, enable readouts of cytokine and prostaglandin E2 (PGE2) production with monocyte, T cell and B cell viability, proliferation, and associated activation markers.

Computational Design of Cyclic Peptide Inhibitors of a Bacterial Membrane Lipoprotein Peptidase.

There remains a critical need for new antibiotics against multi-drug-resistant Gram-negative bacteria, a major global threat that continues to impact mortality rates. Lipoprotein signal peptidase II is an essential enzyme in the lipoprotein biosynthetic pathway of Gram-negative bacteria, making it an attractive target for antibacterial drug discovery. Although natural inhibitors of LspA have been identified, such as the cyclic depsipeptide globomycin, poor stability and production difficulties limit their use in a clinical setting.

Discovery and Derivatization of Tridecaptin Antibiotics with Altered Host Specificity and Enhanced Bioactivity.

The prevalence of multidrug-resistant (MDR) pathogens combined with a decline in antibiotic discovery presents a major challenge for health care. To refill the discovery pipeline, we need to find new ways to uncover new chemical entities. Here, we report the global genome mining-guided discovery of new lipopeptide antibiotics tridecaptin A and tridecaptin D, which exhibit unusual bioactivities within their class.

Facilitators and barriers to community pharmacy PrEP delivery: a scoping review.

Introduction: Pre-exposure prophylaxis (PrEP) is an effective medication to reduce the risk of acquiring HIV. PrEP is available free of charge in the UK from sexual health clinics. Expanding PrEP delivery to community pharmacies holds promise and aligns with UK government goals to eliminate new cases of HIV by 2030.

Invariant NKT cells are more abundant in peanut-allergic adults and a subset of CD8 iNKT cells are depleted after peanut oil exposure.

Introduction: Peanut allergy is one of the most prevalent food allergies globally. Currently, most research into the mechanisms involved in protein allergy focuses on the protein allergens under investigation, and information on the function of accompanying compounds, such as lipids, is scarce. Thus, this research investigates the role of peanut-associated lipids and invariant natural killer T (iNKT) cells in peanut allergy using a novel, human, assay.

Targeting membrane-bound bacterial cell wall precursors: a tried and true antibiotic strategy in nature and the clinic.

Since Fleming's discovery of penicillin nearly a century ago, a bounty of natural product antibiotics have been discovered, many of which continue to be of clinical importance today. The structural diversity encountered among nature's repertoire of antibiotics is mirrored by the varying mechanisms of action by which they selectively target and kill bacterial cells. The ability for bacteria to construct and maintain a strong cell wall is essential for their robust growth and survival under a range of conditions.

Linearization of the Brevicidine and Laterocidine Lipopeptides Yields Analogues That Retain Full Antibacterial Activity.

Brevicidine and laterocidine are macrocyclic lipodepsipeptides with selective activity against Gram-negative bacteria, including colistin-resistant strains. Previously, the macrocyclic core of these peptides was thought essential for antibacterial activity. In this study, we show that C-terminal amidation of linear brevicidine and laterocidine scaffolds, and substitution of the native Thr9, yields linear analogues that retain the potent antibacterial activity and low hemolysis of the parent compounds.

Synthesis and structure-activity relationship studies of N-terminal analogues of the lipopeptide antibiotics brevicidine and laterocidine.

The brevicidine and laterocidine family of lipopeptide antibiotics exhibit strong activity against multidrug-resistant Gram-negative bacteria, while showing low propensity to induce resistance. Both peptides feature a branched lipid tail on the N-terminal residue, which for brevicidine is chiral. Here, we report the synthesis and biological evaluation of a library of brevicidine and laterocidine analogues wherein the N-terminal lipid is replaced with linear achiral fatty acids.

AOA Critical Issues Symposium: I Have an Idea…Now What?

The purpose of this symposium was to provide guidance to innovators as they progress from the idea stage to the product development stage,to the issuing of a patent, and to bringing a product or innovation to market. Finding strategic partnerships is a critical component in taking a good idea and turning it into a successful business. Protecting intellectual property through patents and developing an exit strategy are also important parts of making innovation profitable.

Diesel Aerosols in an Underground Coal Mine.

The case study was conducted in an underground coal mine to characterize submicron aerosols at a continuous miner (CM) section, assess the concentrations of diesel aerosols at the longwall (LW) section, and assess the exposures of selected occupations to elemental carbon (EC) and total carbon (TC). The results show that aerosols at the CM sections were a mixture of aerosols freshly generated at the outby portion of the CM section and those generated in the main drifts that supply "fresh air" to the section. The relatively low ambient concentrations and personal exposures of selected occupations suggest that currently applied control strategies and technologies are relatively effective in curtailing exposures to diesel aerosols.

3,4-Annulated Indoles via Tandem Cyclopropane Ring-Opening/Conia-ene and Michael Addition/Conia-ene Reactions.

4-Alkynyl indoles, when treated with a benzylidene malonate or a donor-acceptor cyclopropane in the presence of a zinc halide, furnished 3,4-hexannylated or 3,4-heptannulated products, respectively, in fair to excellent yields. The reaction proceeds via a tandem addition/Conia-ene cyclization.

Ready for regulatory use: NAMs and NGRA for chemical safety assurance.

New approach methodologies (NAMs) that do not use experimental animals are, in certain settings, entirely appropriate for assuring the safety of chemical ingredients, although regulatory adoption has been slow. In this opinion article we discuss how scientific advances that utilize NAMs to certify systemic safety are available now and merit broader acceptance within the framework of next generation risk assessments (NGRA).

The Role of Lipids in Allergic Sensitization: A Systematic Review.

Immunoglobulin E (IgE)-mediated allergies are increasing in prevalence, with IgE-mediated food allergies currently affecting up to 10% of children and 6% of adults worldwide. The mechanisms underpinning the first phase of IgE-mediated allergy, allergic sensitization, are still not clear. Recently, the potential involvement of lipids in allergic sensitization has been proposed, with reports that they can bind allergenic proteins and act on immune cells to skew to a T helper type 2 (Th2) response.

Synthetic studies with the brevicidine and laterocidine lipopeptide antibiotics including analogues with enhanced properties and efficacy.

Brevicidine and laterocidine are two recently discovered lipopeptide antibiotics with promising antibacterial activity. Possessing a macrocyclic core, multiple positive charges, and a lipidated N-terminus, these lipopeptides exhibit potent and selective activity against Gram-negative pathogens, including polymyxin-resistant isolates. Given the low amounts of brevicidine and laterocidine accessible by fermentation of the producing microorganisms, synthetic routes to these lipopeptides present an attractive alternative.

Binding Studies Reveal Phospholipid Specificity and Its Role in the Calcium-Dependent Mechanism of Action of Daptomycin.

Multidrug-resistant bacteria pose a serious global health threat as antibiotics are increasingly losing their clinical efficacy. A molecular level understanding of the mechanism of action of antimicrobials plays a key role in developing new agents to combat the threat of antimicrobial resistance. Daptomycin, the only clinically used calcium-dependent lipopeptide antibiotic, selectively disrupts Gram-positive bacterial membranes to illicit its bactericidal effect.

Identifying key priorities for research to protect the consumer with food hypersensitivity: A UK Food Standards Agency Priority Setting Exercise.

Introduction: Food hypersensitivity (FHS), including food allergy, coeliac disease and food intolerance, is a major public health issue. The Food Standards Agency (FSA), an independent UK Government department working to protect public health and consumers' wider interests in food, sought to identify research priorities in the area of FHS.

Methods: A priority setting exercise was undertaken, using a methodology adapted from the James Lind Alliance-the first such exercise with respect to food hypersensitivity.