# What is meant by a 'bystander pathogen'?

**URL:** <https://boards.straightdope.com/t/what-is-meant-by-a-bystander-pathogen/852535>\
**Category:** Factual Questions\
**Created:** [April 25, 2020, 3:23am UTC](https://boards.straightdope.com/t/what-is-meant-by-a-bystander-pathogen/852535 "2020-04-25T03:23:19Z")\
**Posts on this page:** 5\
**Page:** 1

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**Author:** ![davidmich](https://avatars.discourse-cdn.com/v4/letter/d/e56c9b/32.png) [@davidmich](https://boards.straightdope.com/u/davidmich)\
**Post date:** [April 25, 2020, 3:23am UTC](https://boards.straightdope.com/t/what-is-meant-by-a-bystander-pathogen/852535/1 "2020-04-25T03:23:19Z")

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Hi

What is meant by a ‘bystander pathogen’?

I look forward to your feedback

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**Author:** ![Chronos](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/chronos/32/134_2.png) [@Chronos](https://boards.straightdope.com/u/Chronos)\
**Post date:** [April 25, 2020, 11:29am UTC](https://boards.straightdope.com/t/what-is-meant-by-a-bystander-pathogen/852535/2 "2020-04-25T11:29:47Z")

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When you’re asking a question like this, you always want to include the context. If you’re wondering about the meaning of a term, it’s because you’ve encountered the term used somewhere. Where?

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**Author:** ![davidmich](https://avatars.discourse-cdn.com/v4/letter/d/e56c9b/32.png) [@davidmich](https://boards.straightdope.com/u/davidmich)\
**Post date:** [April 25, 2020, 11:41am UTC](https://boards.straightdope.com/t/what-is-meant-by-a-bystander-pathogen/852535/3 "2020-04-25T11:41:27Z")

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> [@Chronos](#):
>
> When you’re asking a question like this, you always want to include the context. If you’re wondering about the meaning of a term, it’s because you’ve encountered the term used somewhere. Where?

Very sorry. I was reading an article on  
intestinal permeation enhancers (PEs) and came across the term ‘bystander pathogens’. I could not find a definition for it. It looked like it could be a common medical term but apparently not.

> **[Safety concerns over the use of intestinal permeation enhancers: A mini-review...](https://pubmed.ncbi.nlm.nih.gov/27358756/)**
>
> Intestinal permeation enhancers (PEs) are key components in ∼12 oral peptide formulations in clinical trials for a range of molecules, primarily insulin and glucagon-like-peptide 1 (GLP-1) analogs. The main PEs comprise medium chain fatty acid-based...

The question arises as to whether PEs can cause irreversible epithelial damage and tight junction openings sufficient to permit co-absorption of payloads with bystander pathogens, lipopolysaccharides and its fragment, or exo- and endotoxins that may be associated with sepsis, inflammation and autoimmune conditions.

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**Author:** ![naita](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/naita/32/5862_2.png) [@naita](https://boards.straightdope.com/u/naita)\
**Post date:** [April 25, 2020, 12:28pm UTC](https://boards.straightdope.com/t/what-is-meant-by-a-bystander-pathogen/852535/4 "2020-04-25T12:28:50Z")

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From the full text:

> [@](#):
>
> One of concerns about PEs is that the compromised barrier may allow translocation of potentially dangerous bystanders such as bacteria, viruses, lipopolysaccharide (LPS), LPS fragments, toxins and allergens.

It just means “a pathogen that happens to be in the vicinity and gets across the barrier due to the PE”.

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**Author:** ![davidmich](https://avatars.discourse-cdn.com/v4/letter/d/e56c9b/32.png) [@davidmich](https://boards.straightdope.com/u/davidmich)\
**Post date:** [April 26, 2020, 7:59pm UTC](https://boards.straightdope.com/t/what-is-meant-by-a-bystander-pathogen/852535/5 "2020-04-26T19:59:41Z")

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> [@naita](#):
>
> From the full text:  
> It just means “a pathogen that happens to be in the vicinity and gets across the barrier due to the PE”.

Thanks naita. It makes more sense now.