Bacteriophages the Modern Way | Hacker News Reader

Bacteriophages the Modern Way

science.org

59 pointsflobosg14 comments

It appears that a number of companies are selling products based on bacteriophages, so I wonder how they are overcoming the challenges with production and storage.

The most well-known name in this list is Arm & Hammer.

https://www.bacteriophage.news/phage-products/

I don't know about Arm & Hammer, but some companies don't produce and sell the entire phage but only a specific phage enzyme, that the phage uses to lyse (ruptering of the cell wall) the bacteria (they are called endolysins).

They are much easier to mass produce than phages.

I thought one issue is that our immune system might adapt and kill the phages, making them more of a one-time use per person. Is this true?

They don't infect human cells at all so none of the "I am being attacked" signalling will be coming out of human cells (nor out of the various symbiotic bacteria we live with in and around our body), thus its unlikely it will elicit much of a response. Phages just sit around and do nothing if the right host isn't available and they are so highly specific to the bacteria they infect.

So I don't think so but not much research has been done in the west on phages since the invention of antibiotics.

To my understanding you’re right (ie they don’t affect human cells) but there’s absolutely a chance the human immune system picks them up, but only really if they get in the blood stream. And really this is a secondary concern if that is the goal of treatment, because not doing it means the person probably dies. And due to the extreme sensitivity of a phage to a specific pathogen even having concerns about immune reactions in the future is likely to be a very minor concern given the alternative.

Most phage therapy I have seen/heard of is related to wound care and bacteria that is causing intractable antibiotic resistant infections (either superficial or potentially respiratory). In these environments immune cells cant really effectively do their immune actions (because of the debris, and because a necessary function of effective immunity is effective circulation).

A good going blood borne infection being attacked by bacteriophages would be scary to treat someone through… intravascular bacteria being lysed causes a generalised inflammatory response that amongst other things is hyper coagulable

it looks like our immune system does attack them sometimes and a lot of the successes have been with people on immunosuppressants https://arstechnica.com/science/2021/07/maybe-not-so-fast-wi...

Your immune system attacks plenty of things that are not attacking your cells.

There are multiple different detection mechanisms.

>none of the "I am being attacked" signalling will be coming out of human cells

There's more than enough "I'm being attacked" signalling from the cells attacked by the actual bacteria the phage was meant to address - which is generally about where we also want the phage to be.

I wrote a short futuristic essay on this topic if you are interested: https://glthr.com/continuous-healthcare

What if a therapeutic bacteriophage (mutates and) attacks symbiotic gut bacteria?

Note that 10% of a human's weight and 90% of the cell count are those symbiotic gut bacteria.

> What if a therapeutic bacteriophage (mutates and) attacks symbiotic gut bacteria?

We don't have only one species of bacteria in our gut, and even if it was possible to for it mutate to infect one kind of bacteria in out digestive system it's unlikely (like winning the lottery, a few dozens of times) the phage can can mutations to target all of them. In any case, damages to the human symbiotic bacteria already happens with antibiotics (which damage the entirety of the flora not just a single species).

> Note that 10% of a human's weight

This sounds really fishy.

it's 1%-3%

1. https://www.nih.gov/news-events/news-releases/nih-human-micr...

it's the same issue with antibiotics what if they kill gut bacteria? The answer is they can and do [1]. My guess would be the changes are actually lower with the bacteriophages as they tend to be more specific in the bacteria they target [2] so if that did happen it probably wouldn't cause a widespread die off as much as kill off some specific ones.

1. https://www.healthline.com/health-news/antibiotics-can-kill-... 2. https://arstechnica.com/science/2021/07/maybe-not-so-fast-wi...

Bacteriophages attack only one specific bacteria. Even in the unlikely case that it attacked our gut bacteria, it would be only one species, which would be a tiny minority of you guys bacteria.

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