Bacteriophages More Effective In The Presence Of Human Cells

Some good news: bacteriophage (viruses that infect and kill bacteria) can kill pathogenic bacteria better when in the presence of human cells than when just “in a test tube.”  Abstract:

Bacteriophage therapeutic development will clearly benefit from understanding the fundamental dynamics of in vivo phage-bacteria interactions. Such information can inform animal and human trials, and much can be ascertained from human cell-line work. We have developed a human cell-based system using Clostridium difficile, a pernicious hospital pathogen with limited treatment options, and the phage phiCDHS1 that effectively kills this bacterium in liquid culture. The human colon tumorigenic cell line HT-29 was used because it simulates the colon environment where C. difficile infection occurs. Studies on the dynamics of phage-bacteria interactions revealed novel facets of phage biology, showing that phage can reduce C. difficile numbers more effectively in the presence of HT-29 cells than in vitro. Both planktonic and adhered Clostridial cell numbers were successfully reduced. We hypothesise and demonstrate that this observation is due to strong phage adsorption to the HT-29 cells, which likely promotes phage-bacteria interactions. The data also showed that the phage phiCDHS1 was not toxic to HT-29 cells, and phage-mediated bacterial lysis did not cause toxin release and cytotoxic effects. The use of human cell lines to understand phage-bacterial dynamics offers valuable insights into phage biology in vivo, and can provide informative data for human trials.

Review On Antimicrobial Resistance

Left, a phage.  By Adenosine - Own work, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=8643737

Here is an interesting review on antimicrobial resistance. Such resistance, particularly resistance to antibiotics, is becoming an increasingly significant health concern. Note the mention of phage therapy, which has long been in use in other countries, including some areas of Eastern Europe. That has promise, as one has the wrong types of phages are avoided.  I believe more study on phage therapy should be conducted in the USA. Abstract:

PURPOSE:

To describe the current standards of care and major recent advances with regard to antimicrobial resistance (AMR) and to give a prospective overview for the next 30 years in this field.

METHODS:

Review of medical literature and expert opinion were used in the development of this review.

RESULTS:

There is undoubtedly a large clinical and public health burden associated with AMR in ICU, but it is challenging to quantify the associated excess morbidity and mortality. In the last decade, antibiotic stewardship and infection prevention and control have been unable to prevent the rapid spread of resistant Gram-negative bacteria (GNB), in particular carbapenem-resistant Pseudomonas aeruginosa (and other non-fermenting GNB), extended-spectrum β-lactamase (ESBL)-producing and carbapenem-resistant Enterobacteriaceae (CRE). The situation appears more optimistic currently for Gram-positive, where Staphylococcus aureus, and particularly methicillin-resistant S. aureus (MRSA), remains a cardinal cause of healthcare-associated infections worldwide. Recent advancements in laboratory techniques allow for a rapid identification of the infecting pathogen and antibiotic susceptibility testing. Their impact can be particularly relevant in settings with prevalence of MDR, since they may guide fine-tuning of empirically selected regimen, facilitate de-escalation of unnecessary antimicrobials, and support infection control decisions. Currently, antibiotics are the primary anti-infective solution for patients with known or suspected MDR bacteria in intensive care. Numerous incentives have been provided to encourage researchers to work on alternative strategies to reverse this trend and to provide a means to treat these pathogens. Although some promising antibiotics currently in phase 2 and 3 of development will soon be licensed and utilized in ICU, the continuous development of an alternative generation of compounds is extremely important. There are currently several promising avenues available to fight antibiotic resistance, such as faecal microbiota, and phage therapy.