Phage therapy: A targeted approach to overcoming antibiotic resistance

Isolation and characterization of a phage against the multidrug-resistant Candida albicans ATCC 10231 strain from raw sewage

The financial cost of resistance to antibiotics is constantly increasing. Viruses are possible substitutes and effective treatments for diseases caused by multidrug-resistant pathogens. The aim of the present study is to isolate a Candida albicans virus from raw sewage and characterize it. Herein, direct and enrichment approaches were used for virus isolation from a raw sewage sample collected from the El-Rahmania wastewater treatment plant, El-Behiera Governorate, Egypt. Using a transmission electron microscope, the viral particle was found to have a hexagonal head with a diameter of approximately 160 nm and a short tail with a length of 87 nm. The virus was treated at different temperature ranges (30-90 °C) for 5, 15, 30, and 60 min. The virus titer was stable at 30 °C, 40 °C, and 50 °C for 5-60 min and partially stable at 60 °C, 70 °C, and 80 °C. The virus kept its activity at a wide range between pH 5-10, while it was completely inactivated in highly acidic (pH < 5) and alkaline (pH > 10) conditions. The effect of osmotic shock on the isolated virus showed 64 % survivability. The effects of five organic solvents on viral particles-chloroform, ethanol, methanol, dimethyl sulfoxide (DMSO), and ethyl acetate-showed 0.7, 1.1, 1.2, 1.4, and 1.7 log10 reductions in initial viral titer, respectively. This study provided new information about the characterization of the virus isolated against Candida albicans, which will be useful for future formulation of a successful therapeutic viral agent against Candida albicans.

Bacteriophage therapy for critical antibiotic-resistant Gram-positive bacteria: A systematic review of clinical researches

The emergence of antibiotic-resistant bacteria compromises medical interventions and poses a significant threat to global public health systems. Bacteriophage (phage) therapy offers a promising, natural, safe, and effective antimicrobial alternative, particularly advantageous for combating Gram-positive bacteria with increasing resistance. This systematic review synthesizes clinical cases published in recent 15 years, evaluating the safety and efficacy of phage therapy in treating Gram-positive bacterial infections. It details the mechanisms of action and applications of phages in treating Gram-positive bacterial infections, critically assessing phage cocktail, phage-assisted regimens, and phage-derived agents. The review further studies phage's interaction with human host, commensal microbiota, and immune system. Through the rigorous analysis, it identifies phage therapy's potential implementation obstacles, and provides valuable perspectives for future research and clinical treatment.

Mini-review: Insight of bacteriophage therapy in clinical practice

The emergence of drug-resistant microorganisms requires implementing alternative therapy rather than antibiotics. Phage therapy is a fantastic substitute for antibiotics. Compared to antibiotics, phage therapy has many benefits, such as high specificity for the target bacteria, auto-dosing, biofilm penetration, and a decreased likelihood of resistance development. Regulatory issues, manufacturing barriers, the possibility of phage resistance, and interactions with the human immune system are only a few of the major obstacles that still exist. Various phage-derived enzymes and bioengineered phages may increase the therapeutic potential to combat antibiotic-resistant infections. This mini-review is compiled from research on phage mechanisms in mammalian immune systems, therapeutic uses, regulatory issues, and phage engineering advancements. Thus, it offers a hopeful future in phage therapy by offering a thorough overview of the therapeutic potentiality of phage and the global aspects of phage therapy. In conclusion, phages are expected to become an alternative treatment for antibiotics against multidrug-resistant (MDR) bacteria for medical purposes.

Unveiling the microbial orchestra: exploring the role of microbiota in cancer development and treatment

The human microbiota comprises a diverse microbial ecosystem that significantly impacts health and disease. Among its components, the gut microbiota plays a crucial role in regulating metabolic, immunologic, and inflammatory responses. Dysbiosis, an imbalance in microbial composition, has been linked to carcinogenesis through mechanisms such as chronic inflammation, metabolic disturbances, epigenetic modifications, and immune system dysregulation. Additionally, dysbiosis influences the efficacy and toxicity of cancer therapies. Given these associations, there is growing interest in leveraging the microbiota as a biomarker for cancer detection and outcome prediction. Notably, distinct microbial signatures have been identified across various cancer types, suggesting their potential as diagnostic markers. Furthermore, modulation of the microbiota presents a promising avenue for improving cancer treatment outcomes through strategies such as antibiotics, prebiotics, probiotics, fecal microbiota transplantation, dietary interventions, small-molecule inhibitors, and phage therapy. To explore these relationships, we conducted a comprehensive literature review using Web of Science, Scopus, PubMed, MEDLINE, Embase, and Google Scholar as our primary online databases, focusing on indexed peer-reviewed articles up to the present year. This review aims to elucidate the role of dysbiosis in cancer development, examine the molecular mechanisms involved, and assess the impact of microbiota on cancer therapies. Additionally, we highlight microbiota-based therapeutic strategies and discuss their potential applications in cancer management. A deeper understanding of the intricate interplay between the microbiota and cancer may pave the way for novel approaches to cancer prevention, early detection, and treatment optimization.

Isolation and Genomic Analysis of Escherichia coli Phage AUBRB02: Implications for Phage Therapy in Lebanon

BACKGROUND/OBJECTIVES

Escherichia coli (E. coli), a prevalent Gram-negative bacterium, is a frequent cause of illness. The extensive use of antibiotics has led to the emergence of resistant strains, complicating antimicrobial therapy and emphasizing the need for natural alternatives such as phages.

METHODS

In this study, a novel Escherichia coli phage, AUBRB02, was isolated from sewage and characterized through whole-genome sequencing, host range assays, and biofilm elimination assays. The phage's stability and infectivity were assessed under various pH and temperature conditions, and different E. coli strains.

RESULTS

Phage AUBRB02 has an incubation period of 45 min, a lysis period of 10 min, and a burst size of 30 phages/infected cell. It is stable across pH 5.0-9.0 and temperatures from 4 °C to 60 °C. Treatment with AUBRB02 significantly reduced post-formation E. coli biofilms, as indicated by lower OD values compared with the positive control. The whole genome sequencing revealed a genome size of 166,871 base pairs with a G + C (Guanine and Cytosine content) content of 35.47%. AUBRB02 belongs to the Tequatrovirus genus, sharing 93% intergenomic similarity with its closest RefSeq relative, and encodes 262 coding sequences, including 10 tRNAs.

CONCLUSIONS

AUBRB02 demonstrates high infectivity and stability under diverse conditions. Its genomic features and similarity to related phages highlight its potential for phage therapy, offering promising prospects for the targeted treatment of E. coli infections.

Epidemiology of clinical antimicrobial-resistant Enterobacterales in Togo over three decades: a systematic review and meta-analysis, with recommendations and alternative solutions

BACKGROUND

According to the World Health Organization (WHO), surveillance programs have become essential at national, regional, and global levels to adjust empirical treatments and target interventions to prevent and control the emergence of antimicrobial resistance (AMR). Therefore, this study aimed to conduct the first systematic review and meta-analysis of clinical Enterobacterales resistance to 11 representative antimicrobials from the WHO AWaRe (Access, Watch, Reserve) list, and to provide recommendations to tackle AMR more efficiently in Togo.

METHODS

The Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines (The PRISMA 2020) were used to conduct this study and the protocol was registered with PROSPERO (CRD42024606897). Keywords were used to conduct a systematic literature review of electronic databases. Data analysis was conducted using Stata software version 17.0.

RESULTS

Twenty research articles reporting 9,327 clinical Enterobacterales isolates obtained from 1991 to 2020 were included in this review and were mainly Escherichia coli (6,639; 71.2%), and Klebsiella spp. (2,542; 27.3%), mainly isolated from urine (14 studies; 70%), and pus/wounds (12; 60%). The pooled Enterobacterales resistance rates ranged from 1% (95% CI: 0, 2) imipenem, 3% (95% CI: 1, 5) amikacin, 4% (95% CI: 2, 7) fosfomycin, 50% (95% CI: 40, 60) chloramphenicol, 55% (95% CI: 45, 64) gentamicin, 68% (95% CI: 59, 76) ciprofloxacin, 73% (95% CI: 66, 80) amoxicillin/clavulanic acid (AMC), 79% (95% CI: 71, 86) third-generation cephalosporins (3GC), to 90% (95% CI: 86, 93) sulfamethoxazole/trimethoprim (SXT). The most significant upward trend over 30 years was reported for SXT (R2 = 73.24%, p < 0.001), ciprofloxacin (R2 = 61.44%, p < 0.001), and 3GC (R2 = 18.49%, p < 0.001). Klebsiella spp. strains were significantly more resistant to chloramphenicol (p = 0.03) than E. coli isolates, whereas E. coli isolates were significantly more resistant to amikacin (p = 0.04) than Klebsiella spp. isolates.

CONCLUSION

This study revealed high first-line AMR rates with drastic upward trends in clinical Enterobacterales isolated in Togo over the past 30 years. Thus, the adjustment of empirical antimicrobial treatments in Togo becomes crucial. Moreover, the implementation of prevention policies, whole-genome sequencing approaches, and the promotion of antibiotic stewardship must be enhanced. Finally, alternative therapeutic approaches, such as phytotherapy and phage therapy, were discussed.

CLINICAL TRIAL

Not applicable.

Bacteriophages as Targeted Therapeutic Vehicles: Challenges and Opportunities

Bacteriophages, with their distinctive ability to selectively target host bacteria, stand out as a compelling tool in the realm of drug and gene delivery. Their assembly from proteins and nucleic acids, coupled with their modifiable and biologically unique properties, enables them to serve as efficient and safe delivery systems. Unlike conventional nanocarriers, which face limitations such as non-specific targeting, cytotoxicity, and reduced transfection efficiency in vivo, engineered phages exhibit promising potential to overcome these hurdles and improve delivery outcomes. This review highlights the potential of bacteriophage-based systems as innovative and efficient systems for delivering therapeutic agents. It explores strategies for engineering bacteriophage, categorizes the principal types of phages employed for drug and gene delivery, and evaluates their applications in disease therapy. It provides intriguing details of the use of natural and engineered phages in the therapy of diseases such as cancer, bacterial and viral infections, veterinary diseases, and neurological disorders, as well as the use of phage display technology in generating monoclonal antibodies against various human diseases. Additionally, the use of CRISPR-Cas9 technology in generating genetically engineered phages is elucidated. Furthermore, it provides a critical analysis of the challenges and limitations associated with phage-based delivery systems, offering insights for overcoming these obstacles. By showcasing the advancements in phage engineering and their integration into nanotechnology, this study underscores the potential of bacteriophage-based delivery systems to revolutionize therapeutic approaches and inspire future innovations in medicine.

Bacteriophage Indie resensitizes multidrug-resistant Acinetobacter baumannii to antibiotics in vitro

Antimicrobial resistance in Acinetobacter baumannii poses a significant global health challenge. Phage therapy, particularly through phage-antibiotic synergy (PAS), offers a promising strategy to combat this pathogen. This study demonstrated significant PAS, where the combination of phage Indie and ceftazidime achieved a bacterial reduction of more than 85% of A. baumannii strain AbAK03 at 17 h using low doses. Notably, this combination overcame phage resistance observed at 4 h when the phage was used alone, extending bacterial eradication by 13 h. Furthermore, phage Indie restored bacterial susceptibility to ceftazidime, supporting its role in improving interventional treatments against multidrug-resistant A. baumannii. To explore this interaction, phage Indie was isolated and characterized from multidrug-resistant clinical strains. An in vitro PAS experiment was performed using ceftazidime and piperacillin-tazobactam. The combination of phage Indie with ceftazidime consistently showed superior bactericidal effects compared to either agent alone, while the combination of phage Indie with piperacillin-tazobactam exhibited an antagonistic effect. These findings provide clear evidence supporting the application of phage-antibiotic combinations as an effective intervention strategy and lay the groundwork for future in vivo trials in a mouse model to combat antimicrobial resistance.

Molecular Mechanisms and Emerging Precision Therapeutics in the Gut Microbiota-Cardiovascular Axis

A microbiome in the gut plays a significant role in cardiovascular health and disease. Dysbiosis is an imbalance in the gut microbiome, leading to multiple cardiovascular diseases (CVD) such as atherosclerosis, hypertension, and heart failure. Gut microbe-derived metabolites such as trimethylamine-N-oxide (TMAO) and short-chain fatty acids (SCFAs) are important mediators of the gut-heart axis. Evaluation of the relationship between the gut microbiome and host biomarkers with CVD requires the integration of metagenomics and metabolomics with meta-omics approaches. The literature review found that microbes and metabolic signatures are associated with the risk and progression of CVD. The development of precision therapeutic approaches for targeting gut microbiota includes preventing adverse microbial effects using probiotics, prebiotics, and the drug-as-bug approach to inhibit harmful metabolites of microbiomes, and fecal microbiota transplantation (FMT). However, the implication and practice of these findings in clinical settings face challenges due to the heterogeneity of study designs, difficulty in the determination of causality, and the impact of confounding factors such as diet, medication, and potential inter-individual gut microbiome variability. Future researchers are recommended to conduct longitudinal studies to further establish both gut microbiome associations with CVD and develop successful precision therapeutics approaches based on the microbiome for the treatment of CVD.

Advancements in Antibacterial Therapy: Feature Papers

Antimicrobial resistance (AMR) is a growing global health crisis that threatens the efficacy of antibiotics and modern medical interventions. The emergence of multidrug-resistant (MDR) pathogens, exacerbated by the misuse of antibiotics in healthcare and agriculture, underscores the urgent need for innovative solutions. (1) Background: AMR arises from complex interactions between human, animal, and environmental health, further aggravated by the overuse and inadequate regulation of antibiotics. Conventional treatments are increasingly ineffective, necessitating alternative strategies. Emerging approaches, including bacteriophage therapy, antimicrobial peptides (AMPs), nanotechnology, microbial extracellular vesicles (EVs), and CRISPR-based antimicrobials, provide novel mechanisms that complement traditional antibiotics in combating resistant pathogens. (2) Methods: This review critically analyzes advanced antibacterial strategies in conjunction with systemic reforms such as antimicrobial stewardship programs, the One Health framework, and advanced surveillance tools. These methods can enhance resistance detection, guide interventions, and promote sustainable practices. Additionally, economic, logistical, and regulatory challenges impeding their implementation are evaluated. (3) Results: Emerging technologies, such as CRISPR and nanotechnology, exhibit promising potential in targeting resistance mechanisms. However, disparities in resource distribution and regulatory barriers hinder widespread adoption. Public-private partnerships and sustainable agriculture practices are critical to overcoming these obstacles. (4) Conclusions: A holistic and integrated approach is essential for mitigating the impact of AMR. By aligning innovative therapeutic strategies with global health policies, fostering interdisciplinary collaboration, and ensuring equitable resource distribution, we can develop a sustainable response to this 21st-century challenge.

Frontiers in superbug management: innovating approaches to combat antimicrobial resistance

Anti-microbial resistance (AMR) is a global health issue causing significant mortality and economic burden. Pharmaceutical companies' discontinuation of research hinders new agents, while MDR pathogens or "superbugs" worsen the problem. Superbugs pose a threat to common infections and medical procedures, exacerbated by limited antibiotic development and rapid antibiotic resistance. The rising tide of antimicrobial resistance threatens to undermine progress in controlling infectious diseases. This review examines the global proliferation of AMR, its underlying mechanisms, and contributing factors. The study explores various methodologies, emphasizing the significance of precise and timely identification of resistant strains. We discuss recent advancements in CRISPR/Cas9, nanoparticle technology, light-based techniques, and AI-powered antibiogram analysis for combating AMR. Traditional methods often fail to effectively combat multidrug-resistant bacteria, as CRISPR-Cas9 technology offers a more effective approach by cutting specific DNA sequences, precision targeting and genome editing. AI-based smartphone applications for antibiogram analysis in resource-limited settings face challenges like internet connectivity, device compatibility, data quality, energy consumption, and algorithmic limitations. Additionally, light-based antimicrobial techniques are increasingly being used to effectively kill antibiotic-resistant microbial species and treat localized infections. This review provides an in-depth overview of AMR covering epidemiology, evolution, mechanisms, infection prevention, control measures, antibiotic access, stewardship, surveillance, challenges and emerging non-antibiotic therapeutic approaches.

Transcytosis of T4 Bacteriophage Through Intestinal Cells Enhances Its Immune Activation

Interactions between bacteriophages with mammalian immune cells are of great interest and most phages possess at least one molecular pattern (nucleic acid, sugar residue, or protein structure) that is recognizable to the immune system through pathogen associated molecular pattern (PAMP) receptors (i.e., TLRs). Given that phages reside in the same body niches as bacteria, they share the propensity to stimulate or quench immune responses depending on the nature of their interactions with host immune cells. While most in vitro research focuses on the outcomes of direct application of phages to immune cells of interest, the potential impact of their transcytosis through the intestinal barrier has yet to be considered. As transcytosis through intestinal cells is a necessary step in healthy systems for access by phage to the underlying immune cell populations, it is imperative to understand how this step may play a role in immune activation. We compared the activation of macrophages (as measured by TNFα secretion) following direct phage application to those stimulated by incubation with phage transcytosed through a polarized Caco2 epithelial barrier model. Our results demonstrate that phages capable of activating TNFα secretion upon direct contact maintain the stimulatory capability following transcytosis. Furthermore, activation of macrophages by a transcytosed phage is enhanced as compared to that occurring with an equivalent multiplicity of directly applied phage.

The Appearance of Antiphage Antibodies in Sera of Patients Treated with Phages

Background: Bacteriophages are neutralized by the sera of patients undergoing phage therapy (PT), particularly during local or concomitant local and oral phage administration in bone infections, soft tissue infections, or upper respiratory tract infections. Methods: The antiphage activity of the sera (AAS) level of 27 patients with bacterial infections such as bone infections, soft tissue infections, or upper respiratory tract infections undergoing PT was performed using the plate phage neutralization test. Results: Our preliminary results suggest that high levels of antiphage antibodies appear late in the treatment period, at the earliest in the 3rd-8th week of PT. Patients with bone infections treated locally with the S. aureus phage Staph_1N and patients with upper respiratory tract infections administered locally and orally with the S. aureus phage Staph_A5L had elevated levels of antiphage antibodies in sera during PT. In parallel to these results, it has been shown that a strong antiphage humoral response does not prevent a positive outcome of phage treatment. Conclusions: The earliest time point at which high levels of antiphage antibodies in sera appear during local and oral PT is day 21 of therapy. We noticed that the high level of antiphage antibodies in sera occurring during local or both local and oral PT was correlated with the type of infection and phage type.