Advanced Manufacturing, Formulation and Microencapsulation of Therapeutic Phages.

Manufacturing and formulation of stable, high purity, and high dose bacteriophage drug products (DPs) suitable for clinical usage would benefit from improved process monitoring and control of critical process parameters that affect product quality attributes. Chemistry, Manufacturing, and Controls (CMC) for both upstream (USP) and downstream processes (DSP) need mapping of critical process parameters (CPP) and linking these to critical quality attributes (CQA) to ensure quality and consistency of phage drug substance (DS) and DPs development. Single-use technologies are increasingly becoming the go-to manufacturing option with benefits both for phage bioprocess development at the engineering run research stage and for final manufacture of the phage DS.

Corrigendum: Pathogen genomics and phage-based solutions for accurately identifying and controlling pathogens.

[This corrects the article DOI: 10.3389/fmicb.2023.

Pathogen genomics and phage-based solutions for accurately identifying and controlling pathogens.

is a food-borne pathogen often linked to poultry sources, causing gastrointestinal infections in humans, with the numbers of multidrug resistant (MDR) isolates increasing globally. To gain insight into the genomic diversity of common serovars and their potential contribution to disease, we characterized antimicrobial resistance genes, and virulence factors encoded in 88 UK and 55 Thai isolates from poultry; the presence of virulence genes was detected through an extensive virulence determinants database compiled in this study. Long-read sequencing of three MDR isolates, each from a different serovar, was used to explore the links between virulence and resistance.

Activity of a Bacteriophage Cocktail to Control Growth in Avian, Porcine, and Human Epithelial Cell Cultures.

We examined the activity of phages to control the growth of chicken and swine strains in avian (CHIC-8E11), porcine (IPEC-1), and human (HT-29) cell cultures. We optimized a six-phage cocktail by selecting the five most effective myoviruses and a siphovirus that have optimal lysis on prevalent serovars. We observed ∼20% of 7 log PFU/well phage and 3-6 log CFU bacterial adhesions, and 3-5 log CFU bacterial invasion per 2 cm of the cultured cells at 2 h post-treatment.

Therapeutic effects of oral administration of lytic phages in a mouse model of non-typhoidal salmonellosis.

Acute non-typhoidal salmonellosis (NTS) caused by a Gram-negative bacterium serovar Typhimurium ( Tm) is one of the most common bacterial foodborne diseases worldwide. Bacteriophages (phages) can specifically target and lyse their host bacteria, including the multidrug-resistant strains, without collateral damage to other bacteria in the community. However, the therapeutic use of phages is still poorly investigated.

Microencapsulated bacteriophages incorporated in feed for Salmonella control in broilers.

Bacteriophage inclusion as a feed additive could offer the prospect of its en masse application and reduce the intestinal carriage of Salmonella by broiler chickens. The objective of this study was to evaluate the application of microencapsulated phages as a strategy to control Salmonella and assess the impact of their use during the broiler rearing period. One-hundred one-day-old chicks were randomly divided in two identical poultry houses according to the two experimental groups (control vs Φ-treated group) simulating field production conditions.

Gastrointestinal Dynamics of Non-Encapsulated and Microencapsulated Bacteriophages in Broiler Production.

Bacteriophage therapy is being considered as a promising tool to control in poultry. Nevertheless, changes in gastrointestinal tract environmental conditions throughout the production cycle could compromise the efficacy of phages administered orally. The main objectives of this study were to assess the optimal timing of the phage administration over a 42-day production cycle and to compare microencapsulated and non-encapsulated phages and the spatial and temporal dynamics of the phage delivery along the gastrointestinal tract.

Targeted Delivery of Narrow-Spectrum Protein Antibiotics to the Lower Gastrointestinal Tract in a Murine Model of Colonization.

Bacteriocins are narrow-spectrum protein antibiotics that could potentially be used to engineer the human gut microbiota. However, technologies for targeted delivery of proteins to the lower gastrointestinal (GI) tract in preclinical animal models are currently lacking. In this work, we have developed methods for the microencapsulation of targeting bacteriocins, colicin E9 and Ia, in a pH responsive formulation to allow their targeted delivery and controlled release in an murine model of colonization.

Bacteriophage Encapsulation in pH-Responsive Core-Shell Capsules as an Animal Feed Additive.

Increasing antibiotic resistance in bacteria that cause zoonotic infections is a major problem for farmers rearing animals for food as well as for consumers who eat the contaminated meat resulting in food-borne infections. Bacteriophages incorporated in animal feed may help reduce carriage and infections in animals including chickens and pigs. There are, however, unmet challenges in protecting phages from processing stresses e.

In Vitro and In Vivo Gastrointestinal Survival of Non-Encapsulated and Microencapsulated Bacteriophages: Implications for Bacteriophage Therapy in Poultry.

The therapeutic use of bacteriophages is recognized as a viable method to control . Microencapsulation of phages in oral dosage forms may protect phages from inherent challenges of the gastrointestinal tract in chickens. Therefore, the main objective of this study was to assess the survival of BP FGS011 (non-encapsulated and microencapsulated) through the gastrointestinal tract under in vitro as well as in vivo conditions after oral administration to 1-day-old chicks.

Microencapsulation of Bacteriophages Using Membrane Emulsification in Different pH-Triggered Controlled Release Formulations for Oral Administration.

An -specific phage was encapsulated in three different pH responsive polymer formulations using the process of membrane emulsification. Small 100 µm capsules were fabricated and shown to afford phages suitable acid protection upon exposure to pH 1.5.

Approaches for manufacture, formulation, targeted delivery and controlled release of phage-based therapeutics.

A future successful bacteriophage industry requires development of robust scalable manufacturing platforms for upstream production of high phage titres and their downstream purification and concentration whilst achieving processing yields en route. Development of a broadly applicable process flow sheet employing well-characterised unit operations with knowledge of their critical process parameters is beginning to emerge. A quality-by-design approach is advocated for the development of cost-effective phage production platforms.

An Optimized Bacteriophage Cocktail Can Effectively Control and in .

spp. is a leading cause of gastrointestinal enteritis in humans where it is largely contracted via contaminated poultry and pork. Phages can be used to control infection in the animals, which could break the cycle of infection before the products are accessible for consumption.

Bacteriophage Encapsulation Using Spray Drying for Phage Therapy.

Exploiting the potential of bacteriophages for phage therapy is an exciting future prospect. However, in order to be successful, there is a pressing need for the manufacture of safe and efficacious phage drug products to treat patients. Scalable manufacture of phage biologics as a stable solid dry powder form is highly desirable and achievable using the process of spray drying.

Microencapsulation of Enteric Bacteriophages in a pH-Responsive Solid Oral Dosage Formulation Using a Scalable Membrane Emulsification Process.

A scalable low-shear membrane emulsification process was used to produce microencapsulated -phages in a solid oral dosage form. Uniform pH-responsive composite microparticles (mean size ~100 µm) composed of Eudragit S100 and alginate were produced. The internal microstructure of the gelled microcapsules was studied using ion-milling and imaging, which showed that the microparticles had a solid internal core.

Microencapsulation of -Specific Bacteriophage Felix O1 Using Spray-Drying in a pH-Responsive Formulation and Direct Compression Tableting of Powders into a Solid Oral Dosage Form.

The treatment of enteric bacterial infections using oral bacteriophage therapy can be challenging since the harsh acidic stomach environment renders phages inactive during transit through the gastrointestinal tract. Solid oral dosage forms allowing site-specific gastrointestinal delivery of high doses of phages, e.g.

Staphylococcus aureus resists UVA at low irradiance but succumbs in the presence of TiO photocatalytic coatings.

The aim of this study was to evaluate the bactericidal effect of reactive oxygen species (ROS) generated upon irradiation of photocatalytic TiO surface coatings using low levels of UVA and the consequent killing of Staphylococcus aureus. The role of intracellular enzymes catalase and superoxide dismutase in protecting the bacteria was investigated using mutant strains. Differences were observed in the intracellular oxidative stress response and viability of S.

High Throughput Manufacturing of Bacteriophages Using Continuous Stirred Tank Bioreactors Connected in Series to Ensure Optimum Host Bacteria Physiology for Phage Production.

Future industrial demand for large quantities of bacteriophages e.g., for phage therapy, necessitates the development of scalable Good Manufacturing Practice compliant (cGMP) production platforms.

Nanoencapsulation of Bacteriophages in Liposomes Prepared Using Microfluidic Hydrodynamic Flow Focusing.

Increasing antibiotic resistance in pathogenic microorganisms has led to renewed interest in bacteriophage therapy in both humans and animals. A "Trojan Horse" approach utilizing liposome encapsulated phages may facilitate access to phagocytic cells infected with intracellular pathogens residing therein, e.g.

High precision microfluidic microencapsulation of bacteriophages for enteric delivery.

A Salmonella specific bacteriophage Felix O1 (Myoviridae) was microencapsulated in a pH responsive polymer formulation. The formulation incorporated a pH responsive methacrylic acid copolymer Eudragit® S100 (10% (w/v)) with the addition of the biopolymer sodium alginate, the composition of which was varied in the range (0.5% (w/v)-2% (w/v)).

Expert Opinion on Three Phage Therapy Related Topics: Bacterial Phage Resistance, Phage Training and Prophages in Bacterial Production Strains.

Phage therapy is increasingly put forward as a "new" potential tool in the fight against antibiotic resistant infections. During the "Centennial Celebration of Bacteriophage Research" conference in Tbilisi, Georgia on 26-29 June 2017, an international group of phage researchers committed to elaborate an expert opinion on three contentious phage therapy related issues that are hampering clinical progress in the field of phage therapy. This paper explores and discusses bacterial phage resistance, phage training and the presence of prophages in bacterial production strains while reviewing relevant research findings and experiences.

Microencapsulation of Clostridium difficile specific bacteriophages using microfluidic glass capillary devices for colon delivery using pH triggered release.

The prevalence of pathogenic bacteria acquiring multidrug antibiotic resistance is a global health threat to mankind. This has motivated a renewed interest in developing alternatives to conventional antibiotics including bacteriophages (viruses) as therapeutic agents. The bacterium Clostridium difficile causes colon infection and is particularly difficult to treat with existing antibiotics; phage therapy may offer a viable alternative.

Formulation, stabilisation and encapsulation of bacteriophage for phage therapy.

Against a backdrop of global antibiotic resistance and increasing awareness of the importance of the human microbiota, there has been resurgent interest in the potential use of bacteriophages for therapeutic purposes, known as phage therapy. A number of phage therapy phase I and II clinical trials have concluded, and shown phages don't present significant adverse safety concerns. These clinical trials used simple phage suspensions without any formulation and phage stability was of secondary concern.