Animal research for ME

And another LongCovid study benefitting from mouse models, this time in nature immunology:

https://www.nature.com/articles/s41590-024-01868-z

It conflicts somewhat with the idea that there are no useful mouse models for post-infectious diseases.

 

I can't tell from the abstract whether the findings have been effective in humans. Probably not, as the vast majority of animal experiments produce results which are completely different from those in humans.

 

Did you look at these links, @PeterW?

https://forums.phoenixrising.me/blogs/cancer-researcher-slams-requirement-for-animal-models.1689/

https://forums.phoenixrising.me/blogs/why-differences-matter-more-than-similarities.1574/

https://forums.phoenixrising.me/blo...robiota-fail-to-develop-normal-immunity.1549/

I have a Masters degree in medical science, and focused a good deal on the inappropriateness of animals for research into human conditions.

I don't have much capacity now, so it would be appreciated if you would look at the links.

 

It is reasonable to question why there should be scepticism, but from my perspective the scepticism is founded on years of experience with this sort of study.

The problem with that is that it is only too easy to get a result like that which is pure artefact, combined with some wishful thinking on the part of lab staff. That might sound unfair but I have seen it so many times I know it to be a regular problem. 95% of studies of this sort turn out to be artefacts. Showing genuine autoantibody reactivity to specific tissues is a very taxing exercise. Moreover, human antibodies bind to mouse tissue for various artifactual reasons.

Going back forty years studies with meaningless immunochemical results were common but the peer review process tended to filter them out. That peer review process no longer functions - even the most prestigious sounding journals publish meaningless findings.

Myasthenia and lupus have antibodies that can produce disease in other individuals - most notably in newborn children who have acquired maternal antibody. A few successful experiments were done by people like Alan Pestronk on transferring disease to animals - at least they looked reasonable at the time and people have believed them. I note that at the recent workshop Pestronk's findings were quoted on dose response - rather suggesting that nobody had achieved that in the intervening half century.

If this was a new technique I would give it the benefit of the doubt but nobody except a small cadre of enthusiasts are taking it seriously. There are some well known names making positive noises, I admit, but I fear that simply reflects the way science is done by twitter these days.

 

I think I noticed that Jonathan commented that there had been serendipitous cases i.e. where rituximab had been given to people with autoimmune arthritis and the improvement in their arthritis noted - indicating autoimmune antibodies. So there are "natural" experiments going on - does that reduce the need for animal models - plus they seem to often mislead.
I think I recall that early work on MDNA receptor encephalitis included using cerebrospinal fluid (CSF) from those affected and transferring that (CSF) to mice and then staining the mouse brain - revealing that the autoantibodies had bound to the MDNA receptor. So perhaps it yields useful data some of the time?

 

It would need to provide the correct answers at least 50% of the time, rather than almost never.

 

This study was not testing a finding in humans - it was looking to gain insights into how covid infection might induce cognitive impairment. It was a study to generate hypotheses.

"Here we show that intranasal infection of C57BL/6J mice with SARS-CoV-2 Beta variant leads to central nervous system infiltration of Ly6Chi monocytes and microglial activation. Accordingly, SARS-CoV-2, but not H1N1 influenza virus, increases levels of brain IL-1β and induces persistent IL-1R1-mediated loss of hippocampal neurogenesis, which promotes postacute cognitive deficits.

This type of work simply could not be done in humans - you can't delberately infect a load of people, euthanise them, then pick them apart to understand what has happened in a subset.

The result of this study is a hypothesis which might be further investigated in a number of humans, either dead from other causes, or using imaging systems.

 

I have had a look at the links -

• In the first you quote one person's opinion article - it's not a study of mouse studies, it's opinion.

• In the second your argument is that the systems are different and complex, therefore insights are meaningless. This disregards the ability to look at subsystems and to understand and account for the differences between them. Similarly, Indian culture is different from Italian culture, but both are equally capable of using, programming and developing computers and IT systems. We can and do tailor computers to different cultural requirements because we are sophisticated enough to understand and account for those differences.

• The third - about how mice have different "normal" microbiota to humans is a normal part of understanding the differences between species. It doesn't mean we can't use mice as models, it just means we have to be somewhat more sophisticated in what we learn from them. That is the same for everything. Everything in the modern world has complexities and nuance - nothing is simple.

To your final point about a master's degree in medical science - I would simply point out that the authors of those papers have Professorships in medical sciences. One is the head of the American Association of Immunologists. That doesn't mean that they are always right about everything, but I would be cautious to dismiss their work too readily.

 

That is the part that is still possible. There are and have been several human challenge studies with Covid. The researchers conducting those studies believe that not a single participant developed LC as part of those studies and that is the important part. The piece that leads to LC is not a common occurrence and probably should not be expected to occur in the majority of mice either. Whether mice even have this piece and whether mice can actually develop LC is entirely speculative and based on no good data, as we cannot even measure LC in humans. It's clear that there a massive differences between humans and mice, the authors even start their paper with "the original Wuhan SARS-CoV-2 does not infect mice", whilst there is no data to suggest that the original Wuhan SARS-COV-2 cannot lead to LC. The authors claim that OFT is able to detected cognitive defects in mice due to Covid, if a human equivalent of the OFT had been shown to be useful in LC humans that would seem meaningful, but there is no established test to cognitive defects in LC humans. Quickly glimpsing over the study, it appears to be an acute infection model. Several LC studies however have shown that the cognitive defects that occur in LC seem to on average occur much later, when the acute phase is already over (see for instance https://www.thelancet.com/journals/eclinm/article/PIIS2589-5370(21)00299-6/fulltext# ). If the authors believe that LC in mice is similar to LC in humans they will have to look past the acute infection and see which small percentage of mice stand out from the crowd then. Whether that is then a useful model is an entirely different debate.

So I'm still doubtful about this study having generated a hypothesis that is worth exploring.

I see use for a study such as Iwasakis had it been differently conducted and had they had meaningful sample sizes for all their experiments as well as actual controls.

I think if we want to start making claims about having measured LC in mice for example via some performance test we should first obtain performance tests in humans that quantify LC and then see how translatable those tests are to mice. Before we start speculating based on 0 data.

More recently I've seen the following use of animal models: It is always inherently easy to obtain positive results in animal studies and as such it can be used to motivate federal grants for follow-up work. Whether that is a meaningful approach, I will refrain from discussing, however I'm happy to see some of the follow-up work that will be conducted and that was motivated by such animal studies.

 

OK, but surely the point of these studies is not to give definitive answers... Their objective in these studies is to generate hypotheses. These are ideas which can go on to be investigated further in increasingly appropriate (but perhaps less accessible) systems such as cadavres, organ bank samples or biopsies. But at least they can go to those resources with a few ideas about where to look.

A 1/20 success rate on such hypotheses seems very good to me, especially in a world which sorely lacks ideas of what might be driving ME/CFS.

Surely the theme of most research endeavors is that it's an endless stream of failure with occasional moments of success.

This appears to support the value of animal models, surely?

In a world of few hypotheses, we should be wary of blocking off early stage ideas. I (used to) teach entrpreneurship, and that exact statement can be said about many of today's largest and most successful companies.

 

You're selectively quoting there. I went on to say:

"you can't delberately infect a load of people, euthanise them, then pick them apart to understand what has happened in a subset."

To my knowledge, no study has infected a load of people, euthanised them, and then picked them apart to look at the impact.

I think there's an issue about certainty here - I do not say that such studies prove a hypothesis. If they did, it would not be a hypothesis, it would be knowledge.

But this study has shown that a specific strain of covid does create a material impact on a biological system which could be consistent with the reports of LC. That forms the basis of a hypothesis that can be further examined.

A strong theme coming out of this thread appears to be an expectation that some study will take the field from zero to 100 in a single leap - has that ever been the case in any area of science or engineering? The process is much more likely to start with hints of an idea which are then investigated further, with many failures. Then at some stage, out of hundreds of hypotheses, one stops failing, and we get some genuine knowledge.

If we dismiss every idea which doesn't hit a (metaphorical) "home run" on its first outing, we will never have a decent research sector.

 

Indeed I was selectively quoting to emphasize the fact that if you infect a load of whatevers that doesn't mean that you end-up studying LC, i.e. "that is the part that is still possible". I did so because understanding that part is the crucial part. The fact that no one in human challenge studies seems to have developed LC and what we know about LC prevalence should not be knowledge that should be neglected when looking at models of LC.

The majority of studies you are quoting here are not doing that to generate their hypotheses. Apart from the study by Iwasaki, they are often focused on performance tests and almost never do they perform a subset analysis past the acute phase. Performance tests are certainly a thing we can do in humans and have been doing in humans, we just have no idea how to measure ME/CFS or LC via such performance tests. To pretend like we know how to do it in animals is not based on anything substantial as far as I can tell. That is why I think there are animal studies that could be useful, but it heavily depends on the type of study and given how easy it is to achieve noise in animals studies without knowing how to seperate signal from noise in such studies the amount of meaningful studies are probably very close to zero. That is why apart from ethical reasons there's in my eyes a substantial hurdle in animal studies, they simply aren't worth the investment the majority of time. And the times that they are, the majority will probably agree that it was a sensible approach. I don't think there are too many hardliners on that subject, rather than people thinking we don't need more meaningless results that only dilute our understanding than strengthening it.

I don't think there is an issue about certainty. Everybody knows that you can use a mouse model to generate a hypothesis, simply because those studies always yield results. There is no lack of hypotheses in the LC field. There have been over 100 papers that have claimed to have found some form of biomarker for LC and the number of hypotheses is of a similar length (to name just a very few well known ones: microclots, viral persistence, FND, GPCR aabs, SARS-COV-2 infecting HSC in bone marrow are the root cause of LC, autoimmunity, etc).

What there is a lack of are meaningful hypothesis. Mouse models can be part of that and if someone has a very sensible idea I don't think the charities will object to that, if they would that would indeed be an issue, but I strongly doubt it is. Now I'm not knowledgeable enough historically to know where a mouse model itself was the one thing that lead to a meaningful hypothesis of an illness. Do you have any examples?

 

ME Research UK
From: https://www.meresearch.org.uk/research/research-grants/
"ME Research UK does not fund research which involves the use of animals."

Action for ME
From: https://www.actionforme.org.uk/uploads/pdfs/research-funding-assessment-process.pdf
"our current policy is not to fund medical research projects involving animals. Action for M.E.’s policy on animal use can only be changed with full consultation with our supporting members. We don’t feel this is necessary at this time."

ME Association has slightly more flexibilty: https://meassociation.org.uk/research/
"We would not completely rule out the use of animal research if we were convinced that information from this could lead to an effective form of treatment for ME/CFS and that there was no other way in which this research could be carried out. But this is clearly a hypothetical situation that is very unlikely to occur because any research into the treatment of ME/CFS is being conducted through clinical trials involving human volunteers."

I think Invest In ME Research gets it right: https://www.investinme.org/research-policy.shtml
"We do, however, encourage applications for projects that do not involve animal experiments and support the ethos of Dr Hadwen Trust and therefore we understand that sometimes there are no feasible alternatives and that consideration may need to be given for funding research involving animals as part of a broad spectrum of science that ranges from laboratory studies to clinical trials in patient volunteers."

The issue there is that Invest in ME Research represents only around 3.5% of UK ME Charity research spend - they save across multiple years and then splurge on one project.

 

But clearly ME Research UK and Action for ME does fund research that involves the use of animals as @Jonathan Edwards has already explained, they are not "vegan" in that sense. 2 out of the 4 charities simply oppose to animal model studies as far as I can see.

I think there might also be an underestimation of the complexity of the task at hand. For the sake of simplifing the argument let’s have a look at a hypothetical construct of some of the studies you have been proposing above:

Somewhat reasonable assumptions:

1. Roughly 1 in 20 Covid infections leads to long-lasting syndromic LC in humans.
2. There are several different long-lasting syndromic LC phenotypes that occur at different rates and that sometimes overlap.​

Strong assumptions that lack any evidence:

3. Mice can develop LC.
4. Mice develop the same LC phenotypes that humans develop at the same rate at humans.
5. Mice develop no additional LC phenotypes that humans don’t develop or things that can be misattributed to looking like LC.
6. We can measure LC and these different LC phenotypes in mice.
​

If we accept all of the above assumptions that means any study that wants to do such a thing, including obviously having controls, will have to be studying several hundreds of mice. That is clearly a gargantuan task that no one will ever do. The same probably applies to an EBV infection study for ME/CFS and possibly even to an EBV infection study for MS.

The even easier example would be: If you have a couple 100 of humans and they are all infected with Covid-19 you will not be able to tell which ones have long-lasting Long-Covid unless you ask them questions about their symptomology, which is obviously something you cannot do with mice. Now what you can do with mice is cut them up, but no one has proposed a good study where that would lead to anything.

Now there might be other scenarios and different study set-ups where I could see how the use of animal models is fruitful if the researchers are being extremely careful with controlling for all possible things. But that is simply something that hasn't occured yet, so we are debating something purely hypothetical and in that hypothetical scenario I don't think it would impossible for some of the charities to change their stance. Their stance seems to be very sensible from a historical stand-point, at least from what I can tell as a layman, in that these studies generally don't tell us anything useful.

 

I don't do anything readily. I might well have gone on to do a PhD, but in desperate poverty due to long-standing ME I had to earn some money.

My Masters degree was at the top level (Distinction), so perhaps you can realise how hard it was not to continue studying.

 

I find this very strange. Either you think that the words and phrases used on their websites don’t mean what they say…

or that the charities who say they don’t undertake studies involving animals don’t understand what they are doing.

Both are pretty poor situations in my book.

Regarding using hundreds of mice… why not? This doesn’t strike me as such a “gargantuan” task.

regarding your pts 3,4,5 - disagree. The mice can give clues which can be followed-up using other methods. This idea that mouse studies (or anything else, for that matter) have to be definitive is deeply unhelpful - mouse studies are stepping stones.

 

That indicates that you don't care about animals, whereas I and many others, do.

 

Where are you getting these ideas from? Was the example of lab reagents generated in animals several pages ago not precisely such an example for this being a more nuanced discussion?

Well the studies you have cited only ever used a handful of mice. Perhaps talking to those researchers would be enlightening to many of us to understand why this is a "gargantuan" task that is very expensive, even if ethical reasons are ignored.

I don't think anyone ever suggested that one has to obtain definite answers and that studies can't be stepping stones. What has been said is that you need meaningful stepping stones. If that is not important, then one can simply ask ChatGPT to hallucinate some hypotheses. Whether something is a meaningful stepping stone has been covered by others with more expertise. Instead of getting into an idealogical debate or agreeing and disagreeing without any new arguments, perhaps you can convince me of your viewpoint of the historical use of such studies, as others with sufficient expertise have argued that this historical use is not justified in the larger realm of things.

 

What I care about is maximising our opportunities to understand this awful disease, and avoiding barriers to progress.
If that involves studies on mice undertaken in line with reasonable principles of good practice then yes, I accept that trade-off.

I have real trouble with the moral perfectionist who will look at a person experiencing ME/CFS or severe ME/CFS and say "I'm sorry your life has been ruined by this awful disease, and I'm sorry that millions more will suffer with it for decades, but at least no mice have been harmed."

 

You said "clearly ME Research UK and Action for ME does fund research that involves the use of animals". That directly contradicts their policy.
If you are saying that their policies are not as they say they are, then that is a curious state of affairs.

This overview puts the number of lab mice at between 10 million and 100 million. A couple of hundred mice would be 1/50,000th to 1/500,000th of that figure.

A quick google has thrown this up: https://www.ox.ac.uk/news-and-events/animal-research/research-case-studies
I am sure there are more examples if you care to search for them.