Antibodies to ß adrenergic and muscarinic cholinergic receptors in patients with CFS

[Jonathan Edwards]

Ooh, a bit of role-reversal! Prof. Edwards making the argument (with reservations) for molecular mimicry. Does the fact that quite a few pathogens seem to be able to cause GBS (including flu apparently) mean that molecular mimicry may be more common than is commonly thought?

As I read it the molecular mimicry story for GBS from Willison says that it is always due to one particular organism with mimicry of one particular protein. If that does not stand up to scrutiny then I can go back to mimicry bashing as usual.

 

[BurnA]

They may not be specific but they may be a clue to something related that is specific - but we need to be sure they are a consistent finding first.

Thanks.
Do you think this paper sheds any more light on subsets of ME/CFS or indeed subsets of responders or does it just add noise ?
My understanding is that autoanitbodies were elevated in some patients and they declined in the responders not in the non responders, and that there were responders who didnt have elevated autoantibodies to begin with ( and therefore no decline).

Can it be deciphered how much of the variability is down to the drug response variability amongst patients versus disease variability in patients ? Or are these the same thing - if a patient doesnt respond to a drug is it because they have a distinct disease difference compared to a patient who does respond or can their disease be the same but for another unrelated reason they respond differently?

 

[M Paine]

My question to @BurnA, @M Paine and others who are proposing molecular mimicry, is why do we have to assume that because an infection is a clear trigger for a particular autoimmune illness (e.g. Guillain Barre syndrome) that it must be due to molecular mimicry?

While it is true that the common factor of a pathogenic agent and ME/CFS is a connection which adds some weight to the mimicry idea, the broad range of infectious agents involved seems a deterrent to the mimicry theory. It would seem more likely if there was a set of common microbes or viruses associated with this illness, each with it's own common set of pathology (auto-antibody(s)), however that doesn't appear to be the case so far as far as I understand it.

I have not seen any study related to CFS/ME which demonstrates a consistent connection between any particular pathogen and a a particular auto-antibody, or set of symptoms. I'd love to be corrected here as I confess that I have not read all relevant scientific literature.

I was suggesting looking for that connection via genomics, which is low hanging fruit. I would point out that the act of looking for a connection doesn't mean one expects to find it. Negative results are not always a 'bad' thing, if this type of study ruled out mimicry, it's still a step forward.

As I pointed out earlier, Madeleine Cunningham found some evidence for mimicry, in which a Strep A bacteria protein coat sequence is 85% similar to ß-adrenergic receptors possibly contributing to the pathogenesis of Rheumatic fever.

 

[M Paine]

I'm not sure if this has been posted, but it might be useful if someone is trying to follow this conversation.

Alan Light talks about the Strep/Rheumatic fever link around the 24 minute mark.

 

[M Paine]

http://www.ncbi.nlm.nih.gov/pubmed/24892819

Int Rev Immunol. 2014 Jul-Aug;33(4):314-29. doi: 10.3109/08830185.2014.917411. Epub 2014 Jun 3.
Rheumatic fever, autoimmunity, and molecular mimicry: the streptococcal connection.
Cunningham MW1.

 

[FMMM1]

As I read it the molecular mimicry story for GBS from Willison says that it is always due to one particular organism with mimicry of one particular protein. If that does not stand up to scrutiny then I can go back to mimicry bashing as usual.

Its good to see interest in identifying pathogenic autoimmune antibodies. Among other things finding these antibodies would mean that it would be possible to determine whether a treatment was working or not (levels supressed). Also, finding the epitope (bit antibody binds to) would appear to offer a means of turning off the disease (research, published in Nature Communications in 2014, by scientists at Bristol University re MS).
Others have successfully identified pathogenic autoimmune antibodies which cause acute autoimmune encephalitis e.g. Josep Dalmau (anti-N-methyl-d-aspartate receptor encephalitis) and Sarosh Irani (Voltage-gated Potassium Channel-complex Antibody-associated Limbic Encephalitis).
Silly question: as a layperson I wonder whether the normal stategy is to look for the antibody or the epitope?

How can/can we assist in getting this research carried out via government funding (UK or European)? The European Commission seems to have bucket loads of money for research but I'm guessing that its not that simple. You can make a research suggestion to the National Institute for Health Research (UK) and I think the European Commission. Presumably another alternative would be to go down the route of charity fund raising.

Finally, I've noticed PET (and possibly EEG) scan research published online which is suggested to indicate that ME/CFS suffers have chronic autoimmune encephalitis. Would the "diagnosis" of patients using PET scans strengthen the case for government funded research to identify pathogenic autoimmune antibodies?

 

[Snow Leopard]

Silly question: as a layperson I wonder whether the normal strategy is to look for the antibody or the epitope?

Historically, pathogenic autoantibodies were discovered either by:

1.
Isolating the immune complexes from a lesion and finding out what antigens the antibodies happened to be complexed with.

2.
Scientific intuition - guesses as to what biological pathways must be being disrupted and possible targets.

For example, the discovery autoimmunity in Myasthenia Gravis:

In 1959–1960, Simpson and Nastuck proposed independently that MG has an autoimmune etiology (6, 7) based on several observations: (a) MG patients’ sera compromise contraction in nervemuscle
preparations; (b) the level of serum complement correlates inversely with the severity of MG symptoms; (c) infants of myasthenic mothers may present transient myasthenic symptoms (neonatal MG); (d) inflammatory infiltrates may occur in muscles of MG patients, and pathologic changes are common in their thymi; and (e)
MG may be associated with other putative autoimmune disorders. In 1973, Patrick and Lindstrom demonstrated that rabbits immunized with purified muscle-like AChR developed MG-like symptoms (experimental autoimmune MG [EAMG]) (8). After that seminal discovery, many studies demonstrated an autoimmune response against muscle AChR in MG and the role of anti-AChR Abs in causing the structural and functional damage of the NMJ.

From: Myasthenia gravis: past, present, and future Bianca M. Conti-Fine, Monica Milani, and Henry J. Kaminski http://www.jci.org/articles/view/29894/files/pdf

How can/can we assist in getting this research carried out via government funding (UK or European)? The European Commission seems to have bucket loads of money for research but I'm guessing that its not that simple. You can make a research suggestion to the National Institute for Health Research (UK) and I think the European Commission. Presumably another alternative would be to go down the route of charity fund raising.

The first step is to encourage interested scientists to join the field as they are the ones who are going to be putting in the funding applications.

Finally, I've noticed PET (and possibly EEG) scan research published online which is suggested to indicate that ME/CFS suffers have chronic autoimmune encephalitis. Would the "diagnosis" of patients using PET scans strengthen the case for government funded research to identify pathogenic autoimmune antibodies?

There is a lot of debate on this forum about the relationship between medical imaging results and whether this implies peripheral dysfunction or damage.
Evidence and claims that many patients are suffering from encephalitis, of any cause, including autoimmunity remains speculative.
Current evidence therefore does not justify such research in funding applications. Though if the evidence was much stronger, then it would surely lead to some scientists interested in finding out.

 

[Jonathan Edwards]

Silly question: as a layperson I wonder whether the normal stategy is to look for the antibody or the epitope?

How can/can we assist in getting this research carried out via government funding (UK or European)? The European Commission seems to have bucket loads of money for research but I'm guessing that its not that simple. You can make a research suggestion to the National Institute for Health Research (UK) and I think the European Commission. Presumably another alternative would be to go down the route of charity fund raising.

Finally, I've noticed PET (and possibly EEG) scan research published online which is suggested to indicate that ME/CFS suffers have chronic autoimmune encephalitis. Would the "diagnosis" of patients using PET scans strengthen the case for government funded research to identify pathogenic autoimmune antibodies?

The normal strategy is to take either a section of the tissue you think might contain the antigen or a solution derived from such a tissue run electrophoretically on a Western blot and add the patient's serum followed by a reagent that picks up adherent antibody (often a fluorescent or enzyme conjugated anti-antibody). So the new neural tissue antigens have mostly been found using tissue sections or even intact cells in culture. If the antigen is identified in tissue you usually need to extract it and fully identify what the molecule is by Western blot, as before. Epitopes are individual binding sites on an antigen and identifying these is not often so important and to do so you really need to test for binding of genetically engineered variant of the antigen (with one or other epitope deleted) maybe in combination with cross-competition studies (where you know that two antibodies bind to the same epitope if they compete for binding).

This research is in fact ongoing with charity support. Initial exploratory studies tend not to get funded by big government bodies but labs can often handle exploratory projects without needing huge grants. If new things are found then big grants get put in. European Commission money tends to be earmarked for certain specific types of project and is not always the easiest thing to access but people are working on that. Researchers are also getting together and thinking about how all these different techniques dovetail in terms of collaborative research funding. It is all being thought about and acted on, largely as a result of the initiative of charities.

 

[FMMM1]

The normal strategy is to take either a section of the tissue you think might contain the antigen or a solution derived from such a tissue run electrophoretically on a Western blot and add the patient's serum followed by a reagent that picks up adherent antibody (often a fluorescent or enzyme conjugated anti-antibody). So the new neural tissue antigens have mostly been found using tissue sections or even intact cells in culture. If the antigen is identified in tissue you usually need to extract it and fully identify what the molecule is by Western blot, as before. Epitopes are individual binding sites on an antigen and identifying these is not often so important and to do so you really need to test for binding of genetically engineered variant of the antigen (with one or other epitope deleted) maybe in combination with cross-competition studies (where you know that two antibodies bind to the same epitope if they compete for binding).

This research is in fact ongoing with charity support. Initial exploratory studies tend not to get funded by big government bodies but labs can often handle exploratory projects without needing huge grants. If new things are found then big grants get put in. European Commission money tends to be earmarked for certain specific types of project and is not always the easiest thing to access but people are working on that. Researchers are also getting together and thinking about how all these different techniques dovetail in terms of collaborative research funding. It is all being thought about and acted on, largely as a result of the initiative of charities.

Thank you Snow leopard and Jonathan Edwards for your very detailed responses. I appreciate it.

I'll keep checking for the Zinn eeg paper, further research re PET and definitely research re identification of further autoimmune antibodies.

 

[jimells]

How antibodies could activate the immune system
It turns out that B cells express ß2 Adrenergic receptors, which can play a role in regulation:

Does this apply to plasma cells as well, or do B cells lose this receptor when they turn into plasma cells?

It seems pretty clear to me that I have hyperadrenergic POTS as described in this paper, although I have never had a norepinephrine test to confirm this. I realize this is all just useless speculation, but I am picturing the increase of norepinephrine stimulating the plasma cells to produce antibodies that cause havoc. Certainly, the longer I stand the better the chance of having a bad crash for the next 3-5 days.

 

[Jonathan Edwards]

Does this apply to plasma cells as well, or do B cells lose this receptor when they turn into plasma cells?

It seems pretty clear to me that I have hyperadrenergic POTS as described in this paper, although I have never had a norepinephrine test to confirm this. I realize this is all just useless speculation, but I am picturing the increase of norepinephrine stimulating the plasma cells to produce antibodies that cause havoc. Certainly, the longer I stand the better the chance of having a bad crash for the next 3-5 days.

The annoying thing about plasma cells is that by and large it seems that once they have budded off from an expanding clone of B cells they do not express receptors and do not respond to any signals - they just churn out antibody. This is annoying because you cannot target them through any receptors as a treatment. But that does not invalidate the idea that the receptors are involved in the autoimmune process. B cells expressing adrenergic receptors can be hoodwinked into budding off plasma cells by autoantibodies binding to those receptors. And if these are B cells that make autoantibodies to receptors themselves then you have a neat vicious cycle.

 

[Marco]

But that does not invalidate the idea that the receptors are involved in the autoimmune process. B cells expressing adrenergic receptors can be hoodwinked into budding off plasma cells by autoantibodies binding to those receptors. And if these are B cells that make autoantibodies to receptors themselves then you have a neat vicious cycle.

This thread : http://forums.phoenixrising.me/inde...w-at-me-conference-dr-bansals-research.41363/

discusses Amolak Bansal's theory that 'acquired cortisol resistance' could explain many ME/CFS symptoms including POTS/autonomic instability and the idea of an impaired stress response makes sense (although there's no evidence of a compensatory increase in androgen production as per primary generalized glucocorticoid resistance).

I've been wondering lately about impaired cerebral blood flow as subjectively that's how I feel when faced with a 'stressor'. Given that there's some evidence of cerebral hypoperfusion and elevated basal sympathetic tone in ME/CFS I came across this abstract that suggests that cerebral blood flow increases in response to 'stress' mediated by beta-adrenergic receptors :

Cerebral blood flow and energy metabolism during stress.

http://www.ncbi.nlm.nih.gov/pubmed/2167019

Impaired b-adrenergic receptor function/blockage might result in familiar symptoms and possibly hypoxia activating microglia and might also result in a compensatory increased sympathetic tone?

 

[Gijs]

This thread : http://forums.phoenixrising.me/inde...w-at-me-conference-dr-bansals-research.41363/

discusses Amolak Bansal's theory that 'acquired cortisol resistance' could explain many ME/CFS symptoms including POTS/autonomic instability and the idea of an impaired stress response makes sense (although there's no evidence of a compensatory increase in androgen production as per primary generalized glucocorticoid resistance).

I've been wondering lately about impaired cerebral blood flow as subjectively that's how I feel when faced with a 'stressor'. Given that there's some evidence of cerebral hypoperfusion and elevated basal sympathetic tone in ME/CFS I came across this abstract that suggests that cerebral blood flow increases in response to 'stress' mediated by beta-adrenergic receptors :

Cerebral blood flow and energy metabolism during stress.

http://www.ncbi.nlm.nih.gov/pubmed/2167019

Impaired b-adrenergic receptor function/blockage might result in familiar symptoms and possibly hypoxia activating microglia and might also result in a compensatory increased sympathetic tone?

Well said Marco! This is the key problem for a subgroup of ME/CFS/POTS patiënts. Impaired stress reaction is the cause, i think. The chronic activation of the sympathetic nervous system will also lead to immune problems etc...

 

[jimells]

However from what I remember, the data they had on patients with POTS, they didn't show elevated autoantibodies

You think you can join the dots sometimes but then there is a big hole in the middle.

Does the study report what type of POTS these patients have? Perhaps they didn't have hyperadrenergic POTS

http://www.ncbi.nlm.nih.gov/pubmed/21947988

Clinical presentation and management of patients with hyperadrenergic postural orthostatic tachycardia syndrome. A single center experience.
Kanjwal K1, Saeed B, Karabin B, Kanjwal Y, Grubb BP.
Author information
Abstract
BACKGROUND:
We present our single center experience of 27 patients of hyperadrenergic postural orthostatic tachycardia syndrome (POTS).

METHODS:
... Patients were diagnosed as having the hyperadrenergic form based on an increase in their systolic blood pressure of ≥ 10 mm Hg during the HUTT (2) with concomitant tachycardia or their serum catecholamine levels (serum norepinephnrine level ≥ 600 pg/mL) upon standing.

CONCLUSIONS:
Hyperadrenergic POTS should be identified and differentiated from neuropathic POTS. These patients are usually difficult to treat and there are no standardized treatment protocols known at this time for patients with hyperadrenergic POTS.

 

[kangaSue]

@sillysocks84
That forum you posted is the Dysautonomia Information Network (DINET) forum.

The person you communicated with at Dysautonomia International who said that rituximab works best in cases of POTS or orthostatic intolerance: they must have known patients trying rituximab in order to make a statement like that.

Dysautonomia International only have a Facebook support community.
https://www.facebook.com/DysautonomiaInternational/

 

[kangaSue]

This is likely to be something that only applies to a sub-set but I'm surprised that nicotonic acetylcholine receptor antibodies didn't come up in this thread as one of the possibilities for involvement of autonomic dysfunction in ME/CFS.
http://www.ncbi.nlm.nih.gov/pubmed/18474849

In particular, the alpha3- type ganglionic nicotonic AchR (a3-nAChR, confusingly, it gets called either nicotonic or neuronal AChR) which mediates fast synaptic transmission in sympathetic, parasympathetic, and enteric autonomic ganglia. Impaired cholinergic ganglionic synaptic transmission is one important cause of autonomic failure.

Autoimmune Autonomic Ganglionopathy, AAG (replaces the more generic term Autoimmune Autonomic Neuropathy, AAN) represents one of a small group of autoimmune neuromuscular disorders that are caused by antibodies against ion channels.

Antibodies to the alpha3 nicotonic acetylcholine receptors are found in AAG and may have relevance to this discussion topic by virtue of there also being a co-finding of antibodies to mAChR and alpha and/or beta adrenergic receptors reported in the literature in many instances of AAG.

Antibodies to the a3-nAChR are found in AAG in about 50% of seropositive cases. AAG is reported across a spectrum of other conditions with a degree of autonomic dysfunction, POTS or Orthostatic Hypotension, Sjogren's, Lupus, Scleroderma etc and ranges from mild, might only involve the G.I. system (e.g. slow transit constipation or mild gastroparesis) to disabling, clinically similar to Pure Autonomic Failure. Most texts describe it as of a rapid onset but it has also proven to be of a slowly progressive onset over many years in a restricted form where low titres of antibodies are found.
http://www.hindawi.com/journals/ad/2013/549465/

Symptoms can include cognitive impairment, G.I dysfunction, unexplained chronic pain, sweat disorders and cardiovagal abnormalities and can be an indicator of paraneoplastic syndromes.

There is a commercial test for antibodies to a3-nAChR which I gather is only available in the U.S or U.K. It's helpful that antibody levels are low in controls, in one study, only 1 of 173 healthy controls had an antibody value exceeding 0.02 nmol/L. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3764484/

In this paper from Japan http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4366081/ where the
a3-nAChR test is not available, they used a method called Luciferase Immunoprecipitation Systems (LIPS) for profiling patient sera antibody responses to autoantigens and pathogen antigens associated with infection. Maybe that method can be used to check for mAChR and adrenergic receptor antibodies too.
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3164068/
It makes one wonder if the severity of loss of functionality in chronic conditions is dictated by the amount of different channelopathies happening at the one time rather than a particular channelopathy per se.

 

[kangaSue]

It's interesting to see that antibodies to β2-adrenergic receptors and M2-acetylcholine receptors are prevalent in several cardiac disorders, including Ischemic Heart Disease. Would the same be happening with skeletal muscle from general exertion or exercise-induced ischemia.
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3412294/

I see that Rheumatology is getting interested in this topic too. Antimuscarinic antibodies have been found to occur in Sjogren's Syndrome. In this study http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2990929/ anti-M3R antibodies were found in almost 50% of subjects.The majority of Sjogren's cases also present with ANA antibodies so that's another combination to look for.

 

[MeSci]

Antibodies to the a3-nAChR are found in AAG in about 50% of seropositive cases.

All interesting stuff, but seropositive to what? Maybe I'm being thick (brain a bit knackered from too much to do!) but it they're seropositive to antibodies, antibodies would be found in all of them, wouldn't they?

 

[kangaSue]

All interesting stuff, but seropositive to what? Maybe I'm being thick (brain a bit knackered from too much to do!) but it they're seropositive to antibodies, antibodies would be found in all of them, wouldn't they?

There's nothing wrong with your thinking @MeSci, I was being a bit vague and only mentioning the connection with (ligand-gated ion channel) cholinergic receptors.

Typically, an AAG diagnosis can be made if you test seropositive to the a3-nAChR antibody along with the classic autonomic symptoms however there are some other cation channels antibodies also found in AAG.

So, if you have the typical autonomic symptoms along with antibodies to either N-type calcium channel, P/Q-type calcium channel or Potassium voltage-gated channel VGKC but no antibodies to a3-nAChR, you can still be diagnosed as seronegative (to a3-nAChr) AAG.

http://www.mayomedicallaboratories.com/test-catalog/Clinical+and+Interpreti ve/89886

 

[wastwater]

I was looking at CADASIL the rare genetic disorder as I think this involves cholinergic dysfunction
I'm not suggesting anyone has this,I'm just posting it as a model of what might happen if you had low choline.
Wonder if Donepezil and nicotine would be useful