1. Patients launch $1.27 million crowdfunding campaign for ME/CFS gut microbiome study.
    Check out the website, Facebook and Twitter. Join in donate and spread the word!
ME/CFS and Beating the Clock
For Jody Smith, the ticking of a clock was enough at one time to chase her back to her bed. But with the passage of time, she has been able to reclaim her living room ...
Discuss the article on the Forums.

What is considered low NK cell function?

Discussion in 'Diagnostic Guidelines and Laboratory Testing' started by Nina, May 11, 2010.

  1. Nina

    Nina Senior Member

    Messages:
    220
    Likes:
    14
    Hi everyone,

    I've been wondering for a while what exactly is considered "low" when it comes to NK cell functioning.

    I've had 2 tests so far, the first one was so low that the lab stated they couldn't measure it (??) and the second one came back with about 30%, which is not really low in my opinion. My doc said considering I have active viral infection it should be above 70% though.

    The lab also gave >21% as a reference.

    I do have low NK cell count, but there seems to be some confusion in literature over this issue.

    Would anybody like to share their results (incl. reference range)? Or can you shed some light on this, please?

    Thanks!!
    Nina
  2. Overstressed

    Overstressed Senior Member

    Messages:
    401
    Likes:
    126
    Belgium
    Hi Nina,

    you can check my profiles in another topic 'Immune Profiles'. What has been measured with you, is that the NK-function, or just an absolute count of NK-cells ? In my profile, there is just an absolute count of my NK-cells, and it doesn't say anything of how your NK-cells perform. But, it gives you a picture, if these are measured over a larger period of time.

    With CFS, they usually say that Nk-cell don't perform well. However, it can be that you have normal values of NK-cells, and still bad functioning of the same cells.

    Liebe Gruesse aus Belgien.
    OS.
  3. Athene

    Athene Never give up

    Messages:
    1,130
    Likes:
    147
    Italy
    Hiya,
    My test for NK cells measured "soluble CD57", which I believe is the test of how active the NK cells are. Mine was 40 and the lowest number in a normal person (i.e. anyone without cancer or AIDS) is 60.
    I was told my absolute number of NK cells was also way below normal but I cannot find the data in all my results pages - obviously I don't know what I am looking for so would be interested to find out!
  4. Hope123

    Hope123 Senior Member

    Messages:
    1,141
    Likes:
    531
    My doc and I were initially a bit confused about lab labels since the test result doesn't clearly say "natural killer cell" count or activity. They were instead classified by 'CD'- cluster of differentiation.

    What I understand are that immune cells are like balls with a bunch of "stickers" on them. When the balls pass through a cell counter (flow cytometer), the counter looks at the stickers on each ball and classifies them. NK cells usually don't have the sticker 'CD3' but have the stickers 'CD16' and 'CD56' so they are known as "CD3(-)CD16(+)CD56(+)." CD57 is another type of sticker and since it is soluble that means it is no longer stuck on the immune cell. I think CD57 refers to Lyme disease supposedly but I'm not sure about the evidence for this - I haven't concentrated on Lyme. ("CD4" talked about in HIV refers to the sticker used to identify T-helper cells.)

    http://en.wikipedia.org/wiki/Cluster_of_differentiation

    NK cell activity is often counted in lytic units (LU) -- how well the NK cell can lyse (destroy) foreign cells. The lab I had mine done the value "30" was the lower limit. NK cell activity is, from what I know the major issue, rather than NK cell numbers although the number can be affected as well. NK cell activity has been correlated to severity of CFS by Klimas in one paper. I think that having low, even if not abnormal cell activity, still might be a problem for us.
  5. Dr. Yes

    Dr. Yes Shame on You

    Messages:
    867
    Likes:
    22
    Hi Nina,

    There are a couple tests available on Natural Killer Cells, one being a sort of 'census' in the form of flowcytometric profile (as Hope123 mentioned above, labs usually use the CD3-/CD16+/CD56+ profile to determine NK counts).

    The only commercially available way to really look at NK cell function is with a functional assay, which is done by mixing some of your NK cells with a cancer cell line. They then use flowcytometry to count the number of killed (lysed) cancer cells and the efficiency of your NK cells is represented by the percentage of cancer cells they killed after a certain period of time.

    As I understand it (which may not be that well..), the numbers you get from the lab may vary depending on the ratio of NK cells to cancer cells they use (the higher that ratio, the higher the percentage of lysis), on the length of time they are incubated together (probably standardized these days) and on the specific line of cancer cells used (some are more sensitive to NK cell attacks than others). So it may be difficult to compare results from different labs.

    I don't know what the expected percentage lysis is in NK cells activated due to an active viral infection, but I suppose it depends on the location and type of viral infection and the level of infection. It also would depend on whether you are talking about a chronic, lower-level, re-activating type of infection or an acute one.

    (I don't know if any of this helps at all; I haven't had this test done yet myself.)
  6. JT1024

    JT1024 Senior Member

    Messages:
    534
    Likes:
    288
    Massachusetts
    Dr. Yes... I'm investigating but this isn't easy.

    Some labs test for NK cells and some test for NK and NKT cells. Also, the NK functional assays vary between labs. I've come across different measures of function (LU10 and LU30 with LU30 seeming to be more prevalent so far). As far as normals.... don't have that yet. No wonder docs have trouble interpreting this stuff.....doesn't seem like anyone is on the same page.

    While I'm grateful for still being able to work... barely.. I wish I had more energy/time to research this stuff!

    To be determined...

    NK and NKT cells... the difference between them quantitatively and functionally.

    NK activity testing... is there any standard? I've seen different methodologies so far.... need to determine what methods are out there, reference ranges, and reliability

    I'm brain dead...need sleep...

    Sorry I can't work on this more! :ashamed:
  7. JT1024

    JT1024 Senior Member

    Messages:
    534
    Likes:
    288
    Massachusetts
    Chronic fatigue syndrome is associated with diminished intracellular perforin

    Found an interesting article (from 2005) while researching NK cells. Dr. Nancy Klimas is one of the authors.

    Link to article is here: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1440524/?tool=pubmed

    Abstract

    Chronic fatigue syndrome (CFS) is an illness characterized by unexplained and prolonged fatigue that is often accompanied by abnormalities of immune, endocrine and cognitive functions. Diminished natural killer cell cytotoxicity (NKCC) is a frequently reported finding. However, the molecular basis of this defect of in vitro cytotoxicy has not been described. Perforin is a protein found within intracellular granules of NK and cytotoxic T cells and is a key factor in the lytic processes mediated by these cells.

    Quantitative fluorescence flow cytometry was used to the intracellular perforin content in CFS subjects and healthy controls. A significant reduction in the NK cell associated perforin levels in samples from CFS patients, compared to healthy controls, was observed. There was also an indication of a reduced perforin level within the cytotoxic T cells of CFS subjects, providing the first evidence, to our knowledge, to suggest a T cell associated cytotoxic deficit in CFS. Because perforin is important in immune surveillance and homeostasis of the immune system, its deficiency may prove to be an important factor in the pathogenesis of CFS and its analysis may prove useful as a biomarker in the study of CFS.

    Keywords: chronic fatigue syndrome, cytoplasmic granules, flow cytometry, killer cells natural, perforin
  8. goldiland

    goldiland

    Messages:
    39
    Likes:
    2
    South Florida
    I am actually a Klimas patient and have had many NK tests done over my years with Nancy. As some of you have mentioned, the problem in CFS is not necessarily the number of NK cells, it is their function. Dr. Yes did a nice job of explaining how function is determined and normal controls typically have activity measured between approximately 20% at low end and approximately 40% at high end. The higher the activity, the better your immune system is working. My NK activity is approximately 5% which is consistent with natural killer cell mediated cytotoxicity found in CFS. Hope this helps give you some reference ranges
  9. JT1024

    JT1024 Senior Member

    Messages:
    534
    Likes:
    288
    Massachusetts
    Thanks for the info goldiland!

    You mentioned "normal" NK activity being between 20 and 40. That makes me curious since what I had encountered was LU10 and LU30.... Where did Dr. Klimas have your tests done?

    Too much variance between testing sites and possibly methodologies.

    Thanks again for your information! ~ JT
  10. Anika

    Anika Senior Member

    Messages:
    135
    Likes:
    1
    U.S.
    These posts about the Klimas NK function test remind me that I have also read about NK function tests being sensitive in terms of how soon the blood is tested after it's drawn. I think Dr Klimas's own research lab does the testing, and the results will depend on how long after the draw it's tested - and it needs to be the same day or within 24 hours, something like that, or the reference range is affected.

    That's one reason why I think NK function testing is still fairly rare, but I think they're working on finding ways to test, or other markers, that are less time sensitive and easier to do.
  11. goldiland

    goldiland

    Messages:
    39
    Likes:
    2
    South Florida
    Anika is right regarding both the lab Klimas uses (her own lab through University of Miami) and the time sensitivity required in performing NK function testing.

    The reason to test for NK function is that it is almost universal in CFS patients as a diagnostic biomarker. There are very few diseases (HIV being another) where NK activity is as low as it is within the CFS population. I can tell you that Klimas absolutely uses NK function as a biomarker in diagnosis and is continually remeasuring the activity (along with cytokine levels and other immune components) to assess recovery. For those of you looking to increase NK function.... I've been on immunovir and am currently taking Immpower (medicinal mushrooms). They both have significant studies supporting their immune modulation effects and raise NK function.
  12. ggingues

    ggingues $10 gift code at iHerb GAS343 of $40

    Messages:
    3,918
    Likes:
    784
    Concord, NH
    I had some blood work done and some of the partial data is:

    CD3-CD16+CD56+ (abs) is 159, Reference Range is 70 to 760 Units is /uL (micro Liters)
    CD3-/CD16+CD56+ (%) is 9, Reference Range is 4 to 25

    The was done by Boston Clincial Laboratories, Inc.
    Zahra (Bahi) Sheikhinejad, Ph.D., Director

    My doctor said my immune system is underactive. I always thought it was overactive since I rarely get "sick" anymore. I feel sick all the time, so!! you all know! Anyways my Dr said it is like my immune system is jittery. I also have boosted my Vitamin D (25-Hydroxy) level to 70.3 ng/mL and this was taking 8,000 IUs for 3 to 4 months. I had my Vitamin D tested with my PCP in Oct of 2009 and the level was about 30 or 37 when taking 4,000 IUs, so that is why I doubled my dosage. My Dr said to just take 5000 IUs during the summer. I do not get a lot of sun, work and on the computer a lot. Hope this helps and perhaps someone can tell me something else about my NK numbers?

    Thanks1
  13. JT1024

    JT1024 Senior Member

    Messages:
    534
    Likes:
    288
    Massachusetts
    Immunomodulation by vitamin B12: augmentation of CD8+ T lymphocytes and natural kille

    Another interesting find:

    Immunomodulation by vitamin B12: augmentation of CD8+ T lymphocytes and natural killer (NK) cell activity in vitamin B12-deficient patients by methyl-B12 treatment

    J TAMURA, K KUBOTA,* H MURAKAMI, M SAWAMURA, T MATSUSHIMA, T TAMURA, T SAITOH, H KURABAYSHI,* and T NARUSE

    Third Department of Internal Medicine, Gunma University School of Medicine, Maebashi, Japan
    *Department of Internal Medicine, Kusatsu Branch Hospital, Gunma University Hospital, Kusatsu, Japan
    School of Health Sciences, Gunma University, Maebashi, Japan
    Correspondence: J. Tamura, Third Department of Internal Medicine, Gunma University School of Medicine, 3 Showa-machi, Maebashi 371-8511, Japan.
    Accepted January 7, 1999.

    ABSTRACT

    It has been suggested that vitamin B12 (vit.B12) plays an important role in immune system regulation, but the details are still obscure. In order to examine the action of vit.B12 on cells of the human immune system, lymphocyte subpopulations and NK cell activity were evaluated in 11 patients with vit.B12 deficiency anaemia and in 13 control subjects.

    Decreases in the number of lymphocytes and CD8+ cells and in the proportion of CD4+ cells, an abnormally high CD4/CD8 ratio, and suppressed NK cell activity were noted in patients compared with control subjects. In all 11 patients and eight control subjects, these immune parameters were evaluated before and after methyl-B12 injection.

    The lymphocyte counts and number of CD8+ cells increased both in patients and in control subjects. The high CD4/CD8 ratio and suppressed NK cell activity were improved by methyl-B12 treatment. Augmentation of CD3−CD16+ cells occurred in patients after methyl-B12 treatment. In contrast, antibody-dependent cell-mediated cytotoxicity (ADCC) activity, lectin-stimulated lymphocyte blast formation, and serum levels of immunoglobulins were not changed by methyl-B12 treatment.

    These results indicate that vit.B12 might play an important role in cellular immunity, especially relativing to CD8+ cells and the NK cell system, which suggests effects on cytotoxic cells. We conclude that vit.B12 acts as an immunomodulator for cellular immunity.

    Keywords: vitamin B12, NK cell, CD8, immunomodulation


    More detail here: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1905232/?tool=pubmed
  14. JT1024

    JT1024 Senior Member

    Messages:
    534
    Likes:
    288
    Massachusetts
    No date on this one but more information to digest....


    Decreased Natural Killer Cell Activity Is Associated with Severity of Chronic Fatigue Immune Dysfunction Syndrome
    Emmanuel A. Ojo Amaize, Edward J. Conley, and James B. Peter
    From Specialty Laboratories, Incorporated, Santa Monica, California.
    and the Fatigue Clinic of Michigan, Flint, Michigan.

    Natural killer (NK) cell activity was measured blindly in vitro with blood specimens from 50 healthy individuals and 20 patients with clinically defined chronic fatigue immune dysfunction syndrome (CFIDS) who met the criteria established by the Centers for Disease Control and Prevention (Atlanta). In accordance with a group scoring system of 1-10 points, with 10 being the most severe clinical status, the patient population was stratified into three clinical groups: A (>7 points), B (5-7 points), and C (<5 points). NK cell activity was assessed by the number of lytic units (LU), which for the 50 healthy controls varied between 20 and 250 (50%, 20-50 LU; 32%, 51-100 LU; 6%, 101-130 LU; and 12%, >150 LU). In none of the 20 patients with CFIDS was the NK cell activity >100 LU. For group C, the 10 patients stratified as having the least severe clinical condition, the measure was 61.0 21.7; for group B (more severe, n = 7), it was 18.3 7.3 LU; and for group A (most severe, n = 3), it was 8.0 5.3 LU. These data suggest a correlation between low levels of NK cell activity and severity of CFIDS, which, if it is confirmed by additional studies of larger groups, might be useful for subgrouping patients and monitoring therapy and/or the progression of CFIDS.


    Because of their capability of killing both without prior sensitization and without major histocompatibility requirements, natural killer (NK) cells represent an immune surveillance mechanism independent of classic T cell-mediated immunity [1]. Studies with human and animal subjects have revealed that NK cells are a first-line defense against viruses, bacteria, parasites, and tumors [2-5].

    Compromised or absent natural immunity is associated with acute and chronic viral infections such as AIDS, chronic fatigue immune dysfunction syndrome (CFIDS), psychiatric depression, and various immunodeficiency syndromes [6, 7]. Although its nature is much debated, CFIDS is generally agreed to be characterized by debilitating fatigue and by a number of immunologic abnormalities, the most consistent being a significant depression of NK cell activity [8-10]. The present study was undertaken to determine whether there is an association between low levels of NK cell activity and the severity of clinical conditions of patients with clinically defined CFIDS. Our results confirm and extend previous reports that low NK cell cytotoxicity is a pronounced immunologic abnormality found in some patients with CFIDS [8-10].

    Materials and Methods

    Subjects. Twenty patients (14 females and six males) with clinically defined CFIDS were part of a group of patients in Flint, Michigan, under the care of one of the authors (E.J.C.). All patients met the diagnostic criteria for CFIDS established by the Centers for Disease Control and Prevention (Atlanta). [11]. Blood samples were obtained from these patients and from 50 control subjects whom were also in Flint. The ages of the patients and control subjects ranged from 24 to 50 years. The blood specimens were obtained from all subjects by venipuncture and were collected in 15-mL Vacutainer tubes (Becton Dickinson Vacutainer Systems. Rutherford, NJ) containing preservative-free heparin. The blood samples were drawn at 3:00 P.M. in Michigan and shipped overnight at ambient temperature to reach Specialty Laboratories in Santa Monica, California, by 9:00 the following morning. In previous experiments, we established that blood samples are still suitable for NK cell function tests 18-24 hours after collection. However, there is a 10%-20% decrease in NK cell activity in such samples as compared with that in freshly drawn blood.

    Cytotoxicity assay. Peripheral blood mononuclear cells were isolated by Ficoll-Hypaque (Pharmacia, Uppsala, Sweeden) centrifugation and used as effector cells. NK cell activity was assayed by the measurement of the release of 51Cr in a standard cytotoxicity assay, as previously described [3]. All experiments were performed in triplicate in round-bottomed microtiter plates in RPMI-1640 medium (Irvine Scientific, Santa Ana, CA) supplemented with 10% heat-inactivated fetal bovine serum and 1% penicillin/streptomycin. Assays were performed at four effector-to-target ratios (50:1, 25:1, 12.5:1, and 6.25:1) with use of 2 x 104 target cells/well. K562, an NK cell-sensitive chronic myelogenous leukemia cell line, was used as a source of target cells. The percentage of lysis was converted to lytic units (LU) according to the method of Bryant et al. [12].

    Categorization of patients with CFIDS. Independently of the double-blind measurement of NK cell activity, the 20 patients with CFIDS were globally stratified by one physician into three groups according to duration and severity of their previous physical condition (table 1), as outlined below. On the basis of a group scoring system of 1-10 points, with 10 being the most severe clinical status, the patients were classified as follows: group A, >7 points; group B, 5-7 points; and group C, <5 points.

    On a scale of 1-10, the physical condition of each patient was rated according to the duration of the following features: exhaustion/fatigue, postexertional weakness, arthralgia, myalgia, muscle weakness, twitching, depression, short-term memory loss, neuroirritability, sleep disorders, frequent headaches, fever, chills, nausea/vomiting, abdominal pain, sore throat, lymph node pain, and lymph node enlargement.

    Clinical findings were obtained by a standard physician's examination and globally rated on a scale of 1-10 in regard to the following parameters: temperature; heart rate; respiration rate; findings on examination of lymph nodes (palpable, tender), throat, chest, abdomen (tender), and muscles (tender, lumps); neurological findings; and results of electrocardiography, electroencephalography, and electromyography.

    The subjective severity (based on the duration estimated by each patient) of medically documented and other illnesses or conditions that had occurred in the previous 5 years was globally rated by the physician on a scale of 1-10. The following conditions were considered: viral infections, psychological trauma, complications with pregnancy, and other illnesses enumerated as part of the medical history.

    Personal details (occupation, gender, and race) were also recorded: most of the patients (14 of 20) were Caucasian females who were young adults.

    Statistical Analysis. Statistical comparisons were made with the Student's t-test.

    Results and Discussion

    The reference range of NK cell activity established for the 50 healthy controls was 20-250 LU. For 25 (25%), measurements were 20-50 LU; for 16 (32%), 51-100 LU; for 3 (6%), 101-130 LU; and for 6 (12%), >150 LU (figure 1). In contrast to that in 18% of the controls, in none of the 20 patients with CFIDS was NK cell activity > 100 LU. Those stratified as least severely affected (group C; 10 patients [50%]) had NK cell activity of 61.0 21.7 LU; those with conditions of intermediate severity (group B: 7 patients [35%]) had measures of 18.3 7.3 LU; and the most severely affected (group A: 3 patients [15%]) had measures of 8.0 5.3 LU (figure 1). The NK cell activity of all three groups (A + B + C) was significantly lower than that of the control group (P < .05). Of the three CFIDS groups, only group B (intermediate severity) had NK cell activity that was significantly lower than that of the control group (P <.05). The NK cell activity of group C (least severity) was not significantly different from that of the control group (P = 1.0); this group compromised patients with complaints of the shortest duration and with the least severe affliction according to the global assessment. Although the mean LU of activity in group A (most severity) was lower than that in the control group, the difference between the means was not statistically significant (P = 0.1), a finding that possibly is a reflection of the small sample size of group A.

    Additional blind, controlled studies of NK cell activity in larger groups of patients with CFIDS and in patients with clinically similar problems are needed to validate the stratification of patients with CFIDS into distinct groups. OF course, there almost certainly was substantial overlapping in the complaints of patients in group C and of the control group subjects, perhaps reflecting the fact that those patients' complaintss were of shorter duration than those of group A and B patients. Nevertheless, the preliminary data suggests that a relatively crude, admittedly less-than-objective global stratification of the patients with CFIDS into distinct groups according to the severity or duration of past and current complaints and physical abnormalities might allow identification of laboratory abnormalities that are possibly associated with severity.

    In conclusion, whether the relatively low level of NK cell activities observed in some patients with CFIDS are a cause or effect of CFIDS is presently unknown. We are currently studying a larger group of patients with CFIDS who have been stratified by a similar system with regard to NK cell activity, the presence of antibodies to the early antigen of human herpes virus 6, and the presence of other possibly relevant analytes. However, the fact that NK cell activity decreases with the increased severity and duration of certain clinical variables suggests that measurement of NK cell function could be useful for stratification of patients and possibly for monitoring therapy for and/or the progression of CFIDS.

    Acknowledgments

    The authors are very grateful to Diane Roberts, R.N., for her assistance in providing the patients with CFIDS, and to Shirley C. Chang for technical assistance.

    References

    1. Klas Krr. Natural killing: an unexpected petition for pardon. Current Biology 1992:2:613-5.

    2. Lopez C, Kirkpatrick D, Fitzgerald P. The role of NK (HSV-1) effector cells in the resistance to herpes virus infections in man. In: Herberman RB. ed. NK cells and other effector cells. New York: Academic Press. 1985: 1445-53.

    3. Ojo-Amaize EA, Salimonu LS, Williams AIO, et al. Positive correlation between degree of parasitemia, interferon titers, and natural killer cell activity in Plasmodium falciparum-infected children. J Immunol 1981: i27:2296-300.

    4. Habu S. Akamatsu K, Tamaoki N, Okumura K. In vivo significance of NK cell on resistance against virus (HSV-1) infections in mice. J Immunol 1984:133:2743-7.

    5. Ojo-Amaize EA. Positive correlation between the levels of natural killer cells and the in vivo resistance to syngeneic tumor transplants as influenced by various routes of administration of Corynebacterium parvum bacteria. Cell Immunol 1979:45:182-7.

    6. Whiteside TL, Herberman RB. The role of natural killers cells in human disease. Clin Immunol Immunopathol 1979:45:182-87.

    7. Biron CA. Byron KS, Sullivan JL. Severe herpes virus infections in an adolescent without natural killer cells. N Eng J Med 1989:320:1731-5.

    8. Klimas NG, Salvato FR, Morgan R, Fletcher MA. Immunologic abnormalities in chronic fatigue syndrome. J Clinical Microbiol 1990:28:1403-10.

    9. Gin W, Christiansen FT, Peter JB. Immune function and chronic fatigue syndrome. Med J Aust 1989:151:117-8.

    10. Caligiuri M, Murray C, Buchwald D, et al. Phenotypic and functional deficiency of natural killer cells in patients with chronic fatigue syndrome. J Immunol 1987:139:3306-13.

    11. Holmes GP, Kaplan JE, Gantz NM, et al. Chronic fatigue syndrome: a working case definition. Ann Intern Med 1988:108:387-9.

    12. Bryant J, Day R, Whiteside TL, Herberman RB. Calculation of lytic units for the expression of cell-mediated cytotoxicity. J Immunol Methods 1992: 146:91-103.
  15. Athene

    Athene Never give up

    Messages:
    1,130
    Likes:
    147
    Italy
    Thanks for those articles JT.
    Thanks, everyone, for this great thread.
  16. aiden424

    aiden424

    Messages:
    68
    Likes:
    3
    I had a natural killer cell functional assay. Normal is 8-170. Mine was 11. In the low normal range.
  17. Nina

    Nina Senior Member

    Messages:
    220
    Likes:
    14
    Thanks everybody for your great input!

    The most important take home message for me is that I definitely won't be able to compare my German lab results with what Dr. Klimas does.

    I also wondered since I belong to the group that never gets a flu or fever if the low NK-cell activity should be a marker for that kind of immune system setting as well?

    Definitely more questions arising, but good ones!
  18. Hope123

    Hope123 Senior Member

    Messages:
    1,141
    Likes:
    531
    It looks like your NK cell COUNT is normal but on the lower end of normal. These labs don't tell us anything about function.

    Also, taking one of two (or even more) values as indicative of the immune system being over or underactive may be misleading as the immune system is a complicated network and the way it might be affected by CFS could vary depending on what our true underlying cause is, the co-moribidities we have, our individual variances, etc. This is not to say that NK cell function or another immune measure might not eventually be our biomarker for CFS but rather that things are more complicated -- at the same time, Klimas is interested that NK cell function is down, her papers have also focused on upregulated cytokines indicating an overactive immune system.
  19. Hope123

    Hope123 Senior Member

    Messages:
    1,141
    Likes:
    531
    Thanks for the references, JT.

    The article about severity and NK cell function I referred to earlier as Klimas is I think the same one you posted. (I don't have the energy to dig up the paper in my files to check the name.)

    In terms of B12, I hear she suggests supplementation of B vitamins in some of her patients although I think there was a trial before of B12 in CFS (without B12 deficiency) which was mixed and I found B12 didn't make much difference for me clinically. One of the ID docs I know does suggest a trial of it IM as he finds it helps some people a bit and has little harm.
  20. firefly

    firefly

    Messages:
    87
    Likes:
    10
    Interesting thread. I just had my follow up call with Irma Rey at U. of Miami. Apparently my NK cell function is just over 3 percent. (Lowest normal value for my age and gender is 24 percent.) We are starting immunovir and she is going to discuss with Nancy Klimas on Thursday whether they want to recommend gamma-globulin as well. Apparently some other values were off too.
    I'll post more once I have the hard copy results and can give reference ranges as well.

See more popular forum discussions.

Share This Page