A biomarker in low NK cell activity...

[medfeb]

Re normal range - One speciality lab that I've seen had a normal range of 28.1 +/-11.8. That was for NK cell activity measured as % target cells killed at a 1:1 ratio of target cells to effector cells.

 

[alex3619]

The problems with NK function testing are not the technology any more. Bright cell numbers may also be important as already noted.

The problems stem from test availability and capacity to interpret testing in a research setting.

Strictly defined ME cohorts cannot be directly compared to defined CFS cohorts using loose definitions.

With more inclusive definitions, especially the Oxford definition but including Fukuda, the cohort is probably very heterogeneous. Variations in patient types might induce variations in NK function results, making determination of biomarker status difficult.

Now that we know that it is likely that there is a switch in cytokine status at more or less the three year mark, this is another confound. It will affect even strict ME cohorts. The NK results might well differ based on duration of illness. This will again make interpretation difficult. Short term and long term patients need to be subgrouped in any study. This could be done retrospectively for any study for which we still have data.

 

[Gingergrrl]

What do they class as normal range for the testing? Im guessing each lab may have different reference ranges or different units of measurement .

It was done at OMI via Quest Labs in July and then in Dec 2014. I do not remember the range but I will find out for you. ETA: My NK cell count was completely normal but NK cell functioning was very low and that is the number I am speaking about.

 

[heapsreal]

It was done at OMI via Quest Labs in July and then in Dec 2014. I do not remember the range but I will find out for you. ETA: My NK cell count was completely normal but NK cell functioning was very low and that is the number I am speaking about.

I was similar , normal numbers but low nk function as well as nk bright cell function . Bright cells is a further break down on nk cells into bright and dim cells.

 

[Gingergrrl]

I was similar , normal numbers but low nk function as well as nk bright cell function . Bright cells is a further break down on nk cells into bright and dim cells.

For some reason, I was not tested for bright cell function and either OMI (or Quest?) must not do that test. Did anything concrete treatment wise come from knowing your NK functioning #'s or was it just another academic test?

 

[heapsreal]

For some reason, I was not tested for bright cell function and either OMI (or Quest?) must not do that test. Did anything concrete treatment wise come from knowing your NK functioning #'s or was it just another academic test?

The study was done to look at developing a test or biomarker for cfsme. There was no indication about certain treatments or even trying to increase nk function . Most of the cfs gurus like klimas, peterson etc try to increase nk function.

What would be interesting would be if those cfs drs who test nk function , if they could show results of their patients who have improved with a variety of treatments and see how it correlates with nk function but also in those who have gotten worse and see their nk function .

Also break these groups down into those who have had direct treatment to try and increase nk function with drugs like ampligen or immunovir and see their nk results with their function.

Another group could be those not directly treating nk function but say fit into the antiviral sub group say ebv and with antiviral treatment does nk function improve. Could also do this with cmv annd hhv6 and combinations of them, also a group with chronic bacterial infections .

Im interested to see the rituximab research once its all done to see if they have done before and after nk function testing?

Peterson has had pts on ampligen improve and correlates with increase nk function.

I think theres lots of interesting ways to study nk function but not enough research dollars, as always .

Although its not mentioned, i think alot of the gurus use nk testing as a biomarker?

 

[gregh286]

Biobran is touted quite frequently as a nk activity booster.
http://www.positivehealth.com/article/nutraceuticals/therapeutic-properties-of-biobran-mgn-3

Not sure if there has been any real objective studies conducted with it however.

 

[Jonathan Edwards]

I'd say the studies that dont show low nk function in cfsme are probably done by the UK psychobabblers with some crap criteria which takes patients with multiple conditions other than cfsme . An attempt to discredit cfs biological research and keep it as a psych condition ? ?

That seems an unhelpful level to descend to heaps.

The most recent study that didn't show low nk function was, as I understand it, done by Dr Klimas. That is the nature of the problem!

 

[heapsreal]

That seems an unhelpful level to descend to heaps.

The most recent study that didn't show low nk function was, as I understand it, done by Dr Klimas. That is the nature of the problem!

Do you have a link?

Interested to see where low nk function wasn't found at all, also the criteria they used. Were they klimas patients in the study or not and if they were her patients , were they being treated by her?

Interesting to see the other studies where low nk function wasnt found in cfsme.

 

[heapsreal]

That seems an unhelpful level to descend to heaps.

Just wouldn't suprise me, shonky research on par with pace and get away with it , so far??

 

[Jonathan Edwards]

Thanks for clarifying @Jonathan Edwards
I see what you are saying, but I agree with @duncan that this should mean all the more that someone should set up a proper study with strict diagnostic criteria (or comparisons between criteria), and controls (and maybe stratify the results by illness duration)

Yup. That is precisely why I have joined Charles Shepherd on the Biobank steering committee to support just this work, which has been quietly goin on in the UK for the last few years. I have also joined the committee of the European collaborative project that brings together biobanks throughout Europe to do this. It is the priority and some far -sighted people have spent the last five years getting this set up.

At some point this seems like circular reasoning to say that there are no consistent findings for 100% of patients but then also that the group is heterogenous and we don't know how to subgroup. If it was found to be consistent (and different from controls) even in a large subset of patients wouldn't that be a good way to identify a subgroup?

The problem is that a subset of normal people will have low levels too. You have to show a statistical difference between the whole group and normals before you even think you have something to study. I am not suggesting that 100% of PWME are likely to have low levels - that is what I find implausible in some people's statements. You first have to show that you are not just licking low levels that might equally appear in helathy people - by doing statistics on the whole lot and then you can home in on subsets.

and i think there was some talk that the IOM report almost included it as one, but I can't remember where I read that at the moment.

Maybe these groups are seeing/selecting different patients, but that does seem like even more reason to find out if it is consistent and/or a subgroup.

Being a committee I think IOM had to keep everyone happy a bit. Some members would feel strongly that there was evidence for immune abnormalities. As I understand it there is no consensus on this. We should certainly look for subgroups if we are sure there is a real difference between ME and normal. But that remains unclear. I am not persuaded that we can explain things on the basis of different population selection if some groups are saying that everyone has low levels and others are saying they cannot find any difference from normals. That looks to me more like a problem with the assays.

 

[Jonathan Edwards]

Just wouldn't suprise me, shonky research on par with pace and get away with it , so far??

You may be missing the irony of your comments, heaps.

We do not have citations for studies that do not get published.

 

[A.B.]

IOM report on NK cell function

One of the most consistent findings in ME/CFS subjects is poor NK cell function. Using K562 cells as target cells, 16 of 17 studies reviewed found poor function in subjects compared with healthy controls. However, this finding should be interpreted with caution as even the strongest of these studies are subject to methodological limitations discussed at the beginning of Chapter 4. Furthermore, it is unclear from the description of the methodology of some of the studies whether multiple studies included the same subjects. The largest study compared 176 ME/CFS subjects with 230 healthy controls and found a significant group effect of poorer NK cell function in the ME/CFS cohort (Fletcher et al., 2010). Curriu and colleagues (2013) showed that there were differences in mean cytotoxicity between ME/CFS subjects and healthy controls, but the range was the same. Brenu and colleagues (2012b) studied 65 ME/CFS patients and 21 matched controls in a longitudinal study of three time points over 12 months and found significant deficits in NK cytotoxic activity in the patient group at each time point using peripheral blood mononuclear cells (PBMCs) and a flow cytometric measure of killing. Caligiuri and colleagues (1987) demonstrated reduced cytotoxic activity of ME/CFS NK cells to K562 targets. On the other hand, one study with 26 ME/CFS patients and 50 controls failed to demonstrate impaired NK cell function in the ME/CFS patients using a K562 chromium (Cr) release assay of peripheral blood lymphocytes (PBLs) (Mawle et al., 1997). The authors of this study do not report NK cell counts or CD3-CD56+, but as described, NK numbers generally are not low in ME/CFS.

Low NK cytotoxicity is not specific to ME/CFS. It is also reported to be present in patients with rheumatoid arthritis, cancer, and endometriosis (Meeus et al., 2009; Oosterlynck et al., 1991; Richter et al., 2010). It is present as well in healthy individuals who are older, smokers, psychologically stressed, depressed, physically deconditioned, or sleep deprived (Fondell et al., 2011; Whiteside and Friberg, 1998; Zeidel et al., 2002).

A few studies found a correlation between the severity of NK cell functional impairment and the severity of disease in ME/CFS patients (Lutgendorf et al., 1995; Ojo-Amaize et al., 1994; Siegel et al., 2006). Others looked at mechanisms of cellular dysfunction in ME/CFS and identified abnormalities in early activation markers (Mihaylova et al., 2007) and perforin and granzyme concentration (Maher et al., 2005), as well as in the genes that regulate these cellular functions (Brenu et al., 2011, 2012a). However, no replication studies have been published.

http://www.nap.edu/read/19012/chapter/7#149

 

[heapsreal]

You may be missing the irony of your comments, heaps.

We do not have citations for studies that do not get published.

So how would one know unless involved in this research. Seems abit convenient not to be able to show how and what was tested , which criteria was used, were patients on immunovir etc.

So what you have said, is irrelevant about klimas recent study, that supposedly didnt show low nk function. No facts other than hear say at this stage. Maybe insinuating something about Dr Klimas integrity ? ? Im not sure how to take your reply with no evidence , maybe some type of conflict of interest????

Maybe you could make up a few more other negative studies that werent published as you said there were a few. Thats no good, they weren't published either i suppose. Maybe judy mikovits has all these studies on her laptop??

Maybe its the nurofen that improved their nk function. We need lateral thinkers to understand this connection between nurofen and nk function.

 

[Snow Leopard]

The problem is that it is no good just looking at published studies of NK function because negative studies will either not have been published or the NK findings will be just a line saying nothing was found in a paper focusing on something else.

This sort of publication bias is rarer in ME/CFS research than in other fields because null results are 'expected'. Most people, at least those that have done a proper study will publish their results regardless. The main stuff that is not published is the tiny pilot studies of 5/10 people, often with questionable methodology. I don't believe there is significant publication bias affecting these particular results (NK activity).

That said, just because there is a statistical finding across studies does not mean it is a sensitive, nor specific biomarker. This is the real issue...

 

[Jonathan Edwards]

This sort of publication bias is rarer in ME/CFS research than in other fields because null results are 'expected'. Most people, at least those that have done a proper study will publish their results regardless. The main stuff that is not published is the tiny pilot studies of 5/10 people, often with questionable methodology. I don't believe there is significant publication bias affecting these particular results (NK activity).

How do you know it is rarer, Snow Leopard. In most immunology labs about a quarter of what gets done gets published. The rest gets forgotten because it did not show much or journal referees do not like it much. I am aware of three unpublished studies on NK cells in ME/CFS that found them to be normal - and that is just what people happen to have mentioned. I have not been around asking.

 

[jimells]

I'd say the studies that dont show low nk function in cfsme are probably done by the UK psychobabblers with some crap criteria which takes patients with multiple conditions other than cfsme .

Like this one, perhaps?
(This study didn't test NK cell function, just quantity)

http://www.ncbi.nlm.nih.gov/pubmed/9000046

Clinical improvement in chronic fatigue syndrome is not associated with lymphocyte subsets of function or activation.
Peakman M1, Deale A, Field R, Mahalingam M, Wessely S.
http://www.ncbi.nlm.nih.gov/pubmed/9000046#
Abstract
The relationship between markers of immune function and chronic fatigue syndrome (CFS) is controversial. To examine the relationship directly, 43 subjects with CFS entering a randomized controlled trial of a nonpharmacological treatment for CFS gave samples for immunological analysis before and after treatment.

Percentage levels of total CD3+ T cells, CD4 T cells, CD8 T cells, and activated subsets did not differ between CFS subjects and controls. Naive (CD45RA+ RO-) and memory (CD45RA- RO+) T cells did not differ between subjects and controls. Natural killer cells (CD16+/CD56+/CD3-) were significantly increased in CFS patients compared to controls, as was the percentage of CD11b+ CD8 cells.

There were no correlations between any immune variable and measures of clinical status, with the exception of a weak correlation between total CD4 T cells and fatigue. There was a positive correlation between memory CD4 and CD8 T cells and depression scores and a negative correlation between naive CD4 T cells and depression.

No immune measures changed during the course of the study, and there was no link between clinical improvement as a result of the treatment program and immune status. Immune measures did not predict response or lack of response to treatment.

In conclusion, we have been unable to replicate previous findings of immune activation in CFS and unable to find any important associations between clinical status, treatment response, and immunological status.

This appears to be a secondary paper to another study, but I haven't been able to identify the main paper.

 

[duncan]

S Wessely NOT finding a correlation in a given biomarker - does that suggest we might want to be looking closer at that marker?

 

[minkeygirl]

In the just posted video Forgotten Plague, the first thing Ryan Prior's doctor, Dr Bullington says is wrong, is severely low NK Cell functioning. This is in the first 4 minutes of the video.

 

[Snow Leopard]

I am aware of three unpublished studies on NK cells in ME/CFS that found them to be normal - and that is just what people happen to have mentioned. I have not been around asking.

I can't remember where I saw the figure, but the publication of null findings in this field is notably higher than other fields.

Most of the publication bias in this field arises from singular positive studies with no attempted replication, or replication studies that failed and were not finished (and therefore not published).

If the effect size is not strong (As I mentioned due to the lack of sensitivity/specificity vs CFS criteria) and such studies are underpowered, it is quite possible for there to be such studies even if there is a true effect.

But on this specific issue - three unpublished studies, it seems to me there is an opportunity for such researchers to combine these studies into one paper and do an additional meta-analysis on the NK activity findings in other papers along with analysis of publication bias, eg funnel plots and the like. Such a paper would no doubt be welcome in the newer open access journals committed to combating publication bias.