NK cells and SNP of specific ion channels and receptor genes in ME/cfs

[Kati]

https://www.dovepress.com/articles.php?article_id=26236
open access (click at bottom of page)

Natural killer cells and single nucleotide polymorphisms of specific ion channels and receptor genes in myalgic encephalomyelitis/chronic fatigue syndrome

Authors Marshall-Gradisnik S, Huth T, Chacko A, Johnston S, Smith P, Staines D

Received 29 October 2015
Accepted for publication 3 February 2016
Published 31 March 2016 Volume 2016:9 Pages 39—47
DOI http://dx.doi.org/10.2147/TACG.S99405
Review by Single-blind
Peer reviewers approved by Dr Minghua Wu
Peer reviewer comments 3
Editor who approved publication: Prof. Dr. Martin H. Maurer


1School of Medical Science, 2National Centre for Neuroimmunology and Emerging Diseases, Menzies Health Institute Queensland, Griffith University, Gold Coast, QLD, Australia

Abstract

Aim: The aim of this paper was to determine natural killer (NK) cytotoxic activity and if single nucleotide polymorphisms (SNPs) and genotypes in transient receptor potential (TRP) ion channels and acetylcholine receptors (AChRs) were present in isolated NK cells from previously identified myalgic encephalomyelitis (ME)/chronic fatigue syndrome (CFS) patients.

Subjects and methods: A total of 39 ME/CFS patients (51.69±2 years old) and 30 unfatigued controls (47.60±2.39 years old) were included in this study.

Patients were defined according to the 1994 Centers for Disease Control and Prevention criteria. Flow cytometry protocols were used to examine NK cytotoxic activity.

A total of 678 SNPs from isolated NK cells were examined for 21 mammalian TRP ion channel genes and for nine mammalian AChR genes via the Agena Bioscience iPlex Gold assay. SNP association and genotype was determined using analysis of variance and Plink software.

Results: ME/CFS patients had a significant reduction in NK percentage lysis of target cells (17%±4.68%) compared with the unfatigued control group (31%±6.78%).

Of the 678 SNPs examined, eleven SNPs for TRP ion channel genes (TRPC4, TRPC2, TRPM3, and TRPM8) were identified in the ME/CFS group. Five of these SNPs were associated with TRPM3, while the remainder were associated with TRPM8, TRPC2, and TRPC4 (P<0.05).

Fourteen SNPs were associated with nicotinic and muscarinic AChR genes: six with CHRNA3, while the remainder were associated with CHRNA2, CHRNB4, CHRNA5, and CHRNE (P<0.05).

There were sixteen genotypes identified from SNPs in TRP ion channels and AChRs for TRPM3 (n=5), TRPM8 (n=2), TRPC4 (n=3), TRPC2 (n=1), CHRNE (n=1), CHRNA2 (n=2), CHRNA3 (n=1), and CHRNB4 (n=1) (P<0.05).


Conclusion: We identified a number of SNPs and genotypes for TRP ion channels and AChRs from isolated NK cells in patients with ME/CFS, suggesting these SNPs and genotypes may be involved in changes in NK cell function and the development of ME/CFS pathology. These anomalies suggest a role for dysregulation of Ca2+ in AChR and TRP ion channel signaling in the pathomechanism of ME/CFS

 

[Bob]

I totally don't understand the abstract. Does anyone understand any of it?

 

[Kati]

I totally don't understand the abstract. Does anyone understand any of it?

Essentially, they have identified gene abnormalities associated to ion channels (gate openers, if you will) within the natural killer cells. These ion channels 'open the gate' for acetylcholine, an important neuro-transmitter (messenger). If these are not working well, it explains why our NK cells are not working well.

This is an important discovery.

(i hope I didn't make a fool of myself)

 

[anciendaze]

You didn't make a fool of yourself Kati. These ion channels are not only found on NK cells, but also at neuromuscular junctions. We just learned that Gingergrrl has autoantibodies to N-type calcium channels, which play an important role in the release of acetylcholine from the presynaptic side of neuromuscular junctions. This kind of autoimmune problem is less well known than another at the postsynaptic side of neuromuscular junctions which causes the better-known disease myasthenia gravis. That disease typically involves either inherited defects, antibodies to the acetylcholine receptor itself or to enzymes called muscle kinases needed trigger muscle fiber contractions.

Finding a connection between weird immune behavior and muscle weakness is significant. I doubt many of us have as many problems or such severe ones as Gingergrrl, but she could be like the canary in the coal mine. She has also reported evidence of mast cell activation syndrome, for which she is being treated. I'm still trying to come up to speed on that confusing problem. At the moment it looks like it could cause practically any symptom.

There are known associations of both myasthenia gravis and the newer N-type calcium channel autoimmune problems with a range of autoimmune diseases or neoplasms. I think a picture of at least one type of ME/CFS as an unusual autoimmune disease for which we have not known what to test is starting to form, even if the view is still murky.

 

[Kati]

You didn't make a fool of yourself Kati. These ion channels are not only found on NK cells, but also at neuromuscular junctions. We just learned that Gingergrrl has autoantibodies to N-type calcium channels, which play an important role in the release of acetylcholine from the presynaptic side of neuromuscular junctions. This kind of autoimmune problem is less well known than another at the postsynaptic side of neuromuscular junctions which causes the better-known disease myasthenia gravis. That disease typically involves either inherited defects, antibodies to the acetylcholine receptor itself or to enzymes called muscle kinases needed trigger muscle fiber contractions.

Finding a connection between weird immune behavior and muscle weakness is significant. I doubt many of us have as many problems or such severe ones as Gingergrrl, but she could be like the canary in the coal mine. She has also reported evidence of mast cell activation syndrome, for which she is being treated. I'm still trying to come up to speed on that confusing problem. At the moment it looks like it could cause practically any symptom.

There are known associations of both myasthenia gravis and the newer N-type calcium channel autoimmune problems with a range of autoimmune diseases or neoplasms. I think a picture of at least one type of ME/CFS as an unusual autoimmune disease for which we have not known what to test is starting to form, even if the view is still murky.

But the current study was done on NK cells. Can we generalize and say the problems happens in all the cells?

 

[anciendaze]

But the current study was done on NK cells. Can we generalize and say the problems happens in all the cells?

I don't know that the ion-channels are identical, but it is a safe bet there are many similarities. Ion channels of many types turn up in every kind of cell you can name. When a particular trick works, evolution uses it over and over again.

 

[Kati]

I don't know that the ion-channels are identical, but it is a safe bet there are many similarities. Ion channels of many types turn up in every kind of cell you can name. When a particular trick works, evolution uses it over and over again.

Actually you can see in the open access manuscript that the novel finding suggests that SNP TRPM-3 and TRPM-8 are located in the NK cells.

I will have to read further and perhaps it would be interesting to hear this Marchall-Gradisnik/Staines team speaking and explaining in lay terms what it means.

 

[anciendaze]

Actually you can see in the open access manuscript that the novel finding suggests that SNP TRPM-3 and TRPM-8 are located in the NK cells.

I will have to read further and perhaps it would be interesting to hear this Marchall-Gradisnik/Staines team speaking and explaining in lay terms what it means.

Notice that there is a list of ion channels with similar names. This strongly suggests some common sequence similarity. Finding approximate matches is trickier than finding exact matches, but I'm betting on common sequences turning up in a number of places besides NK cells.

 

[Sea]

There are known associations of both myasthenia gravis and the newer N-type calcium channel autoimmune problems with a range of autoimmune diseases or neoplasms. I think a picture of at least one type of ME/CFS as an unusual autoimmune disease for which we have not known what to test is starting to form, even if the view is still murky.

My father had Myasthenia Gravis. We had many similar symptoms but several quite different ones as well

 

[anciendaze]

I want to add a comment here about what I currently understand about that paper. My understanding is subject to change. The genes they describe are strictly NK cell genes because they only looked at NK cells.

Every nucleated somatic cell in your body carries a full set of genes to make all the other types of cells, but most genes are not active. Immune cells may not have the same exact genome as ordinary somatic cells because they constantly shuffle genes to generate immune responses to novel pathogens. There are diseases in which this takes place at an accelerated rate, which raises the probability of generating an autoimmune response that harms you.

The positive side of this is that finding a defective gene in an immune cell does not mean you are doomed because you lost a genetic lottery at birth. It is possible the change took place at a later date due to environmental challenges.

 

[halcyon]

Every nucleated somatic cell in your body carries a full set of genes to make all the other types of cells, but most genes are not active. Immune cells may not have the same exact genome as ordinary somatic cells because they constantly shuffle genes to generate immune responses to novel pathogens. There are diseases in which this takes place at an accelerated rate, which raises the probability of generating an autoimmune response that harms you.

I haven't read the paper yet and this is stretching far beyond my understanding, but I don't think NK cells do VDJ recombination do they? NKT cells perhaps.

Is it even possible for SNPs to be present on the genome of one cell type but not others? I thought SNPs were body wide and I can't find anything that says otherwise.

 

[Valentijn]

Is it even possible for SNPs to be present on the genome of one cell type but not others?

Yes, SNPs can mutate after birth, and sometimes that mutation can spread to varying extents as the cell replicates. It's basically how species evolve and how inherited mutations come into existence in the first place. If it's a new mutation, it might or might not get passed on to offspring. It's also how cells can become cancerous. But mostly it's normal and won't have any impact at all.

 

[Valentijn]

I don't see any indication that they're correcting for making multiple comparisons, though maybe I'm missing it?

And in Table 3 they're doing bullshit statistics again, showing the percentage of people in each group with a genotype compared to the combined (patient + control) group. This is completely meaningless, because the ME group of patients is 27% larger than the control group.

The data in Table 2 might make for an interesting preliminary finding, but the "significant" results would need to be replicated in new patients and controls for it to even potentially relevant. And with proper corrections for multiple comparisons

 

[A.B.]

Does this have anything to do with a need for magnesium supplementation? I know magnesium and calcium are antagonists and play a role in these ion channels.

 

[Deltrus]

Does this have anything to do with a need for magnesium supplementation? I know magnesium and calcium are antagonists and play a role in these ion channels.

Who knows, magnesium and calcium are basically the same, just magnesium is a smaller atom with a denser charge, so it creates a larger shell of water around it compared to calcium(1)(2). This shell of H2O is what plugs calcium channels when magnesium tries to go through calcium channels. Perhaps damage to calcium channels would let magnesium leak through. Less magnesium in cells would lead to a host of other problems. (calcium leakage from stores INSIDE the cell, potassium deficiency, increased energy consumption etc)

Or perhaps above pharmacological doses of magnesium would help cover up the symptoms of damaged more calcium channels. In this case magnesium would be much less related to the pathology of this type of CFS.

The important thing with this Australian study, is that if they do have an easy way to test for this, then we have an easily testable/fixable form of CFS. If it is confirmed autoimmune, then rituximab should work.

EDIT: nvm this study doesn't have autoantibodies or channel damage in it, just increased numbers of these channels. I'm pretty tired it is like 2 am here. The latter conclusion is more likely than leaky magnesium. Where did I hear about autoantibodies to receptors / ion channels? I am sure I saw a study about it somewhere.. EDIT: ah yeah here.

 

[Bob]

If I understand correctly, this is the type of study that needs to be tested on a very large sample to give us meaningful outcomes; a study such as the large UK 'omics' study. I wonder if the 'omics' study will differentiate (and test) cell types to the same degree. Perhaps the NIH folk should also be aware of this type of research.

 

[thegodofpleasure]

The role of Rituximab is intriguing in this context.
Fluge & Mella seem to be quite sure that its delayed effects were attributable to elimination of auto-antibodies after B cell depletion.

But how does this fit with the discovery of SNPs causing calcium dysregulation?
Perhaps, like everything else associated with this illness, it's more complicated than we've ever previously imagined.

I think that it's quite likely that the Griffith research group are already working on proving whether the same SNP mediated ion channel abnormality exists in other tissues.

Does anyone know whether there is there any knowledge about auto-antibodies causing genetic mutation in other conditions / illnesses?

 

[Bob]

...showing the percentage of people in each group with a genotype compared to the combined (patient + control) group.

Are you sure they've done that, Val? I can't see it stated anywhere in the paper. But I'm struggling to interpret much of it.

 

[Bob]

Interesting snippet... It would be interesting to compare the similarities in SNPs in the research mentioned below...

We have previously identified single-nucleotide polymorphisms (SNPs) in TRP ion channel genes and AChR genes, namely TRPM3, TRPA1, TRPC4,44 CHRM3, CHRNA10, CHRNA5, and CHRNA2 in peripheral blood mononuclear cells from ME/CFS patients.44

Reference:
44. Marshall-Gradisnik S, Smith P, Nilius B, Staines DR. Examination of single nucleotide polymorphisms in acetylcholine receptors in chronic fatigue syndrome patients. Immunol Immunogenet Insights. 2015;7:7–20.

 

[alex3619]

Some of these are calcium channels, and probably most of them (though I have not checked), or are associated with activity in other calcium channels. It points to a possible (as yet unproven) calcium channelopathy, which will involve changes in calcium activated pathways (including acetylcholine related) and intracellular messaging in general. This implies that not only magnesium may have an impact, but also cyclic AMP.

It also suggests, and I do mean its not proven, that there are subtypes of this disorder. In other words, ME might be many different but closely related diseases.

Some pathways might be voltage gated. If so this might have implications for electromagnetic sensitivity.

Some pathways might be triggered by substances found in food. This might have implications for multiple chemical sensitivity.

The implications are intriguing, but such associations as yet prove nothing.

To find out what is implied we will have to look at the tissue distribution for each subtype.

While it is possible that snps can be created during development, this is far less likely than an inherited problem. When it does occur the timing is critical. If it occurs at some stages of development then every tissue that differentiates from that parent tissue will have these issues. That might imply that for many, if acquired and not inherited, that the problem is widely found in immune cells.

I think it far more likely its a general problem.

We do have to look at specific subtypes of channels, as the chemistry for each is a little different.

There are possible links here to the Pall theory of ME and CFS, involving nitric oxide and peroxynitrate, as several of the trigger chemicals for some of these pathways are the same as those proposed by Pall. I have not checked this in detail though.