Objective To investigate in a cross-sectional study the effect of serum-derived exosomes on primary human blood monocyte-derived macrophages (MDMs) comparing exosomes from healthy donors vs patients with relapsing-remitting multiple sclerosis in remission and in relapse and to assess whether the response correlates with exosomal Epstein-Barr virus (EBV) protein expression. Methods A total of 45 serum-derived exosome preparations were isolated from patients and healthy controls and verified for the expression of exosomal and EBV markers. MDMs were differentiated from monocytes for 7 days and incubated for 24 hours with exosomes, and then, cell supernatants were collected for cytokine measurement by cytometric bead array. Cells were immunophenotyped before and after differentiation. Results Serum-derived exosomes of patients with multiple sclerosis (MS) expressed higher levels of EBV proteins than healthy controls. Of interest, expression of EBV nuclear antigen EBNA1 and latent membrane proteins LMP1 and 2A was higher on exosomes derived from patients with active RRMS compared with healthy controls and stable patients. After data normalization, we observed that incubation with EBV(+) exosomes induced CXCL10 and CCL2 secretion by MDMs. MDMs differentiated from patients with active disease were better secretors of CXCL10 and other interferon-γ–inducible chemokines, including CCL2 and CXCL9, than MDMs from healthy and stable MS groups. MDMs from active patients had a higher frequency of a CD14(++) subset that correlated with the secreted CXCL10. Conclusion Exosomes expressing EBV proteins correlate with disease activity and induce an inflammatory response in MDMs that is compounded by the origin of the responder cells.

The unregulated use of antibiotics has led to the rise of antibiotic-resistant bacterial strains. This study explores bacteriophage therapy as an alternative treatment, highlighting its history, significance, and advancements in Europe, the USA, and the Middle East. A comprehensive literature review on bacteriophage therapy was conducted, focusing on its development, clinical trials, and patient treatment applications. The study also examined challenges, limitations, criteria for ideal phage selection, and manipulation techniques. The USA and several European countries have advanced in phage therapy, progressing from clinical trials to patient treatment, while Middle Eastern countries are still in the early stages. Bacteriophages offer specificity, abundance, and minimal side effects, but challenges like safety concerns and potential resistance limit their widespread use. Bacteriophage therapy shows promise as an antibiotic alternative but faces safety and resistance challenges. Continued research and better regulatory frameworks, especially in the Middle East, are needed to realize its potential.

Emerging evidence implicates the envelope protein of human endogenous retrovirus type W (pHERV-W ENV) in the pathogenesis of multiple sclerosis (MS); however, its clinical utility as a biomarker remains incompletely defined. In this study, we demonstrate that pHERV-W ENV is enriched on serum-derived exosomes in patients with relapsing-remitting MS (RRMS), where it reflects both current disease activity and future risk. Exosomal pHERV-W ENV levels were profiled across three cohorts: (1) a cross-sectional cohort including healthy controls, stable MS patients, and patients with active disease; (2) a longitudinal RRMS cohort with samples collected before, during, and after episodes of disease activity; and (3) a retrospective longitudinal cohort of newly diagnosed RRMS patients with three years of follow-up. We observed an increase in exosomal pHERV-W ENV expression during active disease, followed by a decline at follow-up. Levels of pHERV-W ENV expression during active disease positively correlated with Epstein-Barr virus (EBV)-derived latent membrane protein 2 A (LMP2A) expression, supporting an association between endogenous retroviral expression and EBV activity. Flow cytometric profiling of immune cell subsets identified monocytes and B cells as the predominant sources of circulating pHERV-W ENV. Longitudinal profiling further revealed coordinated immune and vascular activation during active disease, including a significant positive correlation between exosomal pHERV-W ENV and the costimulatory molecule CD40. Notably, high baseline levels of exosomal pHERV-W ENV were associated with greater total disease activity events, defined as the sum of clinical relapses and MRI activity (new/enlarging T2 or gadolinium-enhancing (Gd+) lesions) over three years, as well as with accelerated loss of “No Evidence of Disease Activity” (NEDA) status over time. These findings suggest that exosomal pHERV-W ENV expression may serve as a dynamic, non-invasive biomarker of disease activity with prognostic value in MS.

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.

(1) Background: The emergence of multidrug-resistant (MDR) Salmonella enterica poses a major threat to global public health, underscoring the urgent need for alternative therapeutic strategies. Bacteriophages represent a promising alternative due to their high specificity and potent ability to lyse MDR strains. (2) Methods: In this study, we isolated a novel MDR Salmonella Enteritidis-targeting bacteriophage from Lebanese sewage and characterized its host range, thermal and pH stability, and infection dynamics. Whole-genome sequencing was performed using Illumina technology to determine its genetic features and taxonomic classification. (3) Results: the bacteriophage was classified within the genus Jerseyvirus and the class Caudoviricetes with a 43 kb dsDNA genome encoding 66 open reading frames (ORFs). It demonstrated remarkable thermal stability, retaining infectivity after prolonged incubation at 65 °C, and showed a broad host range. The phage formed large, clear plaques, displayed rapid adsorption (>97% within 3 min), a short latent period (20 min), and a burst size of ~32 PFU per cell. Genome analysis revealed no lysogeny, virulence, or resistance genes, confirming its strictly lytic nature and supporting its potential use as a biocontrol agent. (4) Conclusions: These findings identify SA01 as a novel, strictly lytic, and thermally stable bacteriophage with strong potential as a biocontrol agent against multidrug-resistant Salmonella Enteritidis. Its broad host range suggests potential activity also against other Salmonella enterica serovars, supporting its applicability in food safety and biotechnology.

1) Background: The emergence of multidrug-resistant (MDR)-Salmonella enterica poses a major threat to global public health underscoring the urgent need for alternative therapeutic strategies where bacteriophages are a promising candidate due to their high specificity and potent ability to lyse MDR strains.2) Methods: In this study, we isolated a novel MDR-Salmonella Enteritidis-targeting bacteriophage from Lebanese sewage and characterized its host range, thermal and PH stability, and infection dynamics. Whole-genome sequencing was performed by Illumina to determine genetic features and taxonomic position.3) Results: the bacteriophage belongs to genus Jerseyvirus and Class Caudoviricetes with a 43kb dsDNA genome and 66 ORFs. It demonstrated extraordinary thermal stability, retaining infectivity after prolonged incubation at 65 °C, showed a broad host range, produced large, clear plaques, displayed rapid adsorption (>97% within 3 min), a short latent period (20 min), and a burst size of ~320 PFU per cell. Genome analysis revealed no lysogeny, virulence, or resistance genes, confirming its strictly lytic nature and supporting its potential use as a biocontrol agent. 4) Conclusions: These findings identify SA01 as a novel, strictly lytic, and thermally stable bacteriophage with strong potential as a biocontrol agent against multidrug-resistant Salmonella Enteritidis, supporting its potential activity also against other Salmonella enterica serovars for future applications in food safety and biotechnology.