Myalgic Encephalomyelitis/Chronic Fatigue Syndrome as a Hyper-Regulated Immune System Driven by an Interplay Between Regulatory T Cells and Chronic Human Herpesvirus Infections

Abstract:

Autoimmunity and chronic viral infections are recurrent clinical observations in Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS), a complex disease with an unknown cause. Given these observations, the regulatory CD4+ T cells (Tregs) show promise to be good candidates for the underlying pathology due to their capacity to suppress the immune responses against both self and microbial antigens. Here, we discussed the overlooked role of these cells in the chronicity of Human Herpes Virus 6 (HHV6), Herpes Simplex 1 (HSV1), and Epstein-Barr virus (EBV), as often reported as triggers of ME/CFS.

Using simulations of the cross-regulation model for the dynamics of Tregs, we illustrated that mild infections might lead to a chronically activated immune responses under control of Tregs if the responding clone has a high autoimmune potential. Such infections promote persistent inflammation and possibly fatigue. We then hypothesized that ME/CFS is a condition characterized by a predominance of this type of infections under control of Tregs. In contrast, healthy individuals are hypothesized to trigger immune responses of a virus-specific clone with a low autoimmune potential.

According to this hypothesis, simple model simulations of the CD4+ T-cell repertoire could reproduce the increased density and percentages of Tregs observed in patients suffering from the disease, when compared to healthy controls. A deeper analysis of Tregs in the pathogenesis of ME/CFS will help to assess the validity of this hypothesis.

Copyright © 2019 Sepúlveda, Carneiro, Lacerda and Nacul.

Source: Sepúlveda N, Carneiro J, Lacerda E, Nacul L. Myalgic Encephalomyelitis/Chronic Fatigue Syndrome as a Hyper-Regulated Immune System Driven by an Interplay Between Regulatory T Cells and Chronic Human Herpesvirus Infections. Front Immunol. 2019 Nov 21;10:2684. doi: 10.3389/fimmu.2019.02684. eCollection 2019. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6883905/ (Full article)

Study finds differences in energy use by immune cells in ME/CFS

Press Release: New findings published in the Journal of Clinical Investigation suggest that specific immune T cells from people with myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) show disruptions in the way they produce energy. The research was supported by the National Institutes of Health.

“This research gives us additional evidence for the role of the immune system in ME/CFS and may provide important clues to help us understand the mechanisms underlying this devastating disease,” said Vicky Whittemore, Ph.D., program director at NIH’s National Institute of Neurological Disorders and Stroke (NINDS), which partially funded the study.

ME/CFS is a severe, chronic, and debilitating disease that can cause a range of symptoms including pain, severe exhaustion, cognitive impairment, and post-exertional malaise, the worsening of symptoms after physical or mental activity. Estimates suggest that between 836,000 and 2.5 million people in the United States may be affected by ME/CFS. It is unknown what causes the disease and there are no treatments.

Research by Alexandra Mandarano and collaborators in the laboratory of Maureen Hanson, Ph.D., professor of molecular biology and genetics at Cornell University in Ithaca, New York, examined biochemical reactions involved in energy production, or metabolism, in two specific types of immune cells obtained from 45 healthy controls and 53 people with ME/CFS. Investigators focused on CD4 T cells, which alert other immune cells about invading pathogens, and CD8 T cells, which attack infected cells. Dr. Hanson’s team used state-of-the-art methods to look at energy production by the mitochondria within T cells, when the cells were in a resting state and after they had been activated. Mitochondria are biological powerhouses and create most of the energy that drives cells.

Dr. Hanson and her colleagues did not see significant differences in mitochondrial respiration, the cell’s primary energy-producing method, between healthy and ME/CFS cells at rest or after activation. However, results suggest that glycolysis, a less efficient method of energy production, may be disrupted in ME/CFS. Compared to healthy cells, CD4 and CD8 cells from people with ME/CFS had decreased levels of glycolysis at rest. In addition, ME/CFS CD8 cells had lower levels of glycolysis after activation.

“Our work demonstrates the importance of looking at particular types of immune cells that have different jobs to do, rather than looking at them all mixed together, which can hide problems specific to particular cells,” said Dr. Hanson. “Additional studies focusing on specific cell types will be important to unravel what’s gone wrong with immune defenses in ME/CFS.”

Dr. Hanson’s group also looked at mitochondrial size and membrane potential, which can indicate the health of T cell mitochondria. CD4 cells from healthy controls and people with ME/CFS showed no significant differences in mitochondrial size nor function. CD8 cells from people with ME/CFS showed decreased membrane potential compared to healthy cells during both resting and activated states.

Dr. Hanson’s team examined associations between cytokines, chemical messengers that send instructions from one cell to another, and T cell metabolism. The findings revealed different, and often opposite, patterns between healthy and ME/CFS cells, suggesting changes in the immune system. In addition, the presence of cytokines that cause inflammation unexpectedly correlated with decreased metabolism in T cells.

This study was supported in part by the NIH’s ME/CFS Collaborative Research Network, a consortium supported by multiple institutes and centers at NIH, consisting of three collaborative research centers and a data management coordinating center. The research network was established in 2017 to help advance research on ME/CFS.

“In addition to providing valuable insights into the immunology of ME/CFS, we hope that the results coming out of the collaborative research network will inspire more researchers, particularly those in the early stages of their careers, to work on this disease,” said Joseph Breen, Ph.D., section chief, Immunoregulation Section, Basic Immunology Branch, National Institute of Allergy and Infectious Diseases (NIAID), which partially funded the study.

Future research studies will examine metabolism in other subsets of immune cells. In addition, researchers will investigate ways in which changes in metabolism affect the activity of T cells.

This study was supported by NINDS grant U54NS105541, NIAID grant R21AI117595, Simmaron Research, and an anonymous private donor.

NINDS (https://www.ninds.nih.gov/) is the nation’s leading funder of research on the brain and nervous system. The mission of NINDS is to seek fundamental knowledge about the brain and nervous system and to use that knowledge to reduce the burden of neurological disease.

About the National Institutes of Health (NIH): NIH, the nation’s medical research agency, includes 27 Institutes and Centers and is a component of the U.S. Department of Health and Human Services. NIH is the primary federal agency conducting and supporting basic, clinical, and translational medical research, and is investigating the causes, treatments, and cures for both common and rare diseases. For more information about NIH and its programs, visit www.nih.gov.

NIH…Turning Discovery Into Health®

Reference: Mandarano et al. “Myalgic encephalomyelitis/chronic fatigue syndrome patients exhibit altered T cell metabolism and cytokine associations,” Journal of Clinical Investigation. December 12, 2019

Can you get to Worcester, Mass., to donate blood for researchers?

From Mass ME Association:

Can you get to Worcester, Mass., to donate blood for researchers?

MassME is excited to be working with Liisa Selin, PhD, and Anna Gil, PhD, of the University of Massachusetts Medical School, in Worcester, Massachusetts. Even more exciting, these trailblazing researchers were just awarded a Ramsey grant by the Solve ME/CFS Initiative. More details: https://solvecfs.org/liisa-selin-and-anna-gil/

Liisa and Anna recently said, “We are personally aware of the devastation that ME/CFS causes and the challenge of surviving each day with this disease. We are therefore very excited by our recent findings of a unique subset of T cells that may play a role in ME/CFS immunopathogenesis and its potential to be a biomarker.”

Want to show these ME/CFS researchers a little love? Can you make the trip to Worcester, MA, 1 hour west of Boston to donate blood? They are looking for men and women aged 18 years or older with ME/CFS. Healthy men and women aged 18 years or older are also welcome.

Blood donors get $20. The researchers would need at least 30 mL of your blood — and up to 60 mL, if you are willing and able. They would like to get the first set of blood samples in December and before January 21st. The first scheduled date and time is this coming Monday, December 16, from 2 pm to 4 pm. Please contact our coordinator Jeanne Perrin at <jeanne2911@outlook.com> or 781-392-4708 as soon as possible if you can join us on Monday or to arrange another time. Jeanne will give you location and parking information.

Please feel free to forward this notice to other people with ME/CFS who might be interested.

Understanding neuromuscular disorders in chronic fatigue syndrome

Abstract:

Muscle failure has been demonstrated in patients with myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS). Neurophysiological tools demonstrate the existence of both central and peripheral fatigue in these patients. Central fatigue is deduced from the reduced amplitude of myopotentials evoked by transcranial magnetic stimulation of the motor cortex as well as by the muscle response to interpolated twitches during sustained fatiguing efforts. An impaired muscle membrane conduction velocity assessed by the reduced amplitude and lengthened duration of myopotentials evoked by direct muscle stimulation is the defining feature of peripheral fatigue.

Some patients with ME/CFS show an increased oxidative stress response to exercise. The formation of lipid hydroperoxides in the sarcolemma, which alters ionic fluxes, could explain the reduction of muscle membrane excitability and potassium outflow often measured in these patients. In patients with ME/CFS, the formation of heat shock proteins (HSPs) is also reduced. Because HSPs protect muscle cells against the deleterious effects of reactive oxygen species, the lack of their production could explain the augmented oxidative stress and the consecutive alterations of myopotentials which could open a way for future treatment of ME/CFS.

Copyright: © 2019 Jammes Y and Retornaz F.

Source: Jammes Y, Retornaz F. Understanding neuromuscular disorders in chronic fatigue syndrome.F1000Res. 2019 Nov 28;8. pii: F1000 Faculty Rev-2020. doi: 10.12688/f1000research.18660.1. eCollection 2019. https://www.ncbi.nlm.nih.gov/pubmed/31814961

Efficacy and safety of Sijunzi Decoction for chronic fatigue syndrome with spleen deficiency pattern: study protocol for a randomized, double-blind, placebo-controlled trial

Abstract:

BACKGROUND: Chronic fatigue syndrome (CFS), which is characterized by severe and disabling fatigue, has become an extensively concerned medical disorder in clinical practice. Due to the unclear etiology, current treatments are symptomatic or need assistance from psychology and kinesiology. Under the immature conditions in China, many patients would seek help from traditional Chinese medicine (TCM), in which Chinese herbal medicine (CHM) is one of the main interventions. Sijunzi Decoction (SJZD) is a classical formula and has been utilized in improving fatigue symptoms for a long time. However, lack of rigorously-designed randomized controlled trial limits its application and generalization in CFS management. Hence, we design this clinical trial to assess the effectiveness and safety of SJZD for CFS.

METHODS: This is a single-center, randomized, double-blind, placebo-controlled trial. Two hundred and twelve patients with CFS will be recruited from public and equally allocated to SJZD group and placebo group. Based on the general education, these two groups will receive corresponding drugs twice a day for consecutive 2 months. The follow-up period will be 1 month. The primary outcome will be the change of Chalder fatigue scoring after treatment. Secondary outcomes include the short form-36 physical function subscale (SF36-PF), spleen deficiency rating scale, quality of life and self-rated clinical global impression (CGI) scales.

DISCUSSION: The four ingredients of SJZD are Renshen (Radix Ginseng), Baizhu (Rhizoma Atractylodis Macrocephalae), Fulin (Poria) and Zhigancao (Radix Glycyrrhizae Preparata), which show potential to alleviate CFS on the foundation of available studies. The results of this trial will provide high-quality clinical evidence for the application of SJZD, and hope to further support a new TCM choice in CFS treatment.

TRIAL REGISTRATION: ISRCTN23930966 (ISRCTN registry, registered on 28th May, 2019).

Source: Dai L, Zhou WJ, Wang M, Zhou SG, Ji G. Efficacy and safety of Sijunzi Decoction for chronic fatigue syndrome with spleen deficiency pattern: study protocol for a randomized, double-blind, placebo-controlled trial. Ann Transl Med. 2019 Oct;7(20):587. doi: 10.21037/atm.2019.09.136. https://www.ncbi.nlm.nih.gov/pubmed/31807568

Intimate Partner Violence and the Risk of Developing Fibromyalgia and Chronic Fatigue Syndrome

Abstract:

Intimate partner violence (IPV) is a global public health issue with a variety of ill health consequences associated with exposure. Due to the stimulation of chronic stress and inflammatory pathways, childhood abuse has been associated with the subsequent development of functional syndromes such as fibromyalgia and chronic fatigue syndrome (CFS). Although IPV in women appears to elicit similar biochemical responses, this association has not been tested thoroughly in IPV survivors. These functional syndromes are complex in etiology and any indication of their risk factors would benefit health care professionals managing this population. Therefore, we aimed to investigate the association between exposure to IPV with functional syndromes: fibromyalgia and CFS.

We conducted a retrospective open cohort study using “The Heath Improvement Network” database between January 1, 1995 and December 1, 2017. A total of 18,547 women who were exposed to IPV were each matched by age to four controls who were not exposed (n = 74,188). The main outcome measures were the risk of developing fibromyalgia and CFS. These were presented as adjusted incidence rate ratios (aIRR) with 95% confidence intervals (CIs).

We found that 97 women in the exposed group developed fibromyalgia (incidence rate [IR] = 1.63 per 1,000 person-years) compared to 239 women in the unexposed group (IR = 0.83 per 1,000 person-years). Following adjustment, this translated to an IRR of 1.73 (95% CI = [1.36, 2.22]). Similarly, 19 women developed CFS in the exposed group (IR = 0.32 per 1,000 person-years), compared to 53 in the unexposed group (0.18 per 1,000 person-years), which translates to an aIRR of 1.92 (95% CI = [1.11, 3.33]).

Therefore, we have identified an association between a history of IPV in women and the development of these functional syndromes, which may provide more information to inform the biopsychosocial pathway precipitating the development of fibromyalgia and CFS.

Source: Chandan JS, Thomas T, Raza K, Bradbury-Jones C, Taylor J, Bandyopadhyay S1, Nirantharakumar K. Intimate Partner Violence and the Risk of Developing Fibromyalgia and Chronic Fatigue Syndrome. J Interpers Violence. 2019 Dec 6:886260519888515. doi: 10.1177/0886260519888515. [Epub ahead of print] https://www.ncbi.nlm.nih.gov/pubmed/31805821

Myalgic encephalomyelitis/chronic fatigue Syndrome (ME/CFS): Investigating care practices pointed out to disparities in diagnosis and treatment across European Union

Abstract:

ME/CFS is a chronic, complex, multisystem disease that often limits the health and functioning of the affected patients. Diagnosing patients with ME/CFS is a challenge, and many different case definitions exist and are used in clinical practice and research. Even after diagnosis, medical treatment is very challenging. Symptom relief and coping may affect how patients live with their disease and their quality of life. There is no consensus on which diagnostic criteria should be used and which treatment strategies can be recommended for patients.

The purpose of the current project was to map the landscape of the Euromene countries in respect of national guidelines and recommendations for case definition, diagnosis and clinical approaches for ME/CFS patients. A 23 items questionnaire was sent out by email to the members of Euromene. The form contained questions on existing guidelines for case definitions, treatment/management of the disease, tests and questionnaires applied, and the prioritization of information for data sampling in research. We obtained information from 17 countries. Five countries reported having national guidelines for diagnosis, and five countries reported having guidelines for clinical approaches.

For diagnostic purposes, the Fukuda criteria were most often recommended, and also the Canadian Consensus criteria, the International Consensus Criteria and the Oxford criteria were used. A mix of diagnostic criteria was applied within those countries having no guidelines. Many different questionnaires and tests were used for symptom registration and diagnostic investigation. For symptom relief, pain and anti-depressive medication were most often recommended. Cognitive Behavioral Therapy and Graded Exercise treatment were often recommended as disease management and rehabilitative/palliative strategies.

The lack of consistency in recommendations across European countries urges the development of regulations, guidance and standards. The results of this study will contribute to the harmonization of diagnostic criteria and treatment for ME/CFS in Europe.

Source: Strand EB, Nacul L, Mengshoel AM, Helland IB, Grabowski P, Krumina A, Alegre-Martin J, Efrim-Budisteanu M, Sekulic S, Pheby D, Sakkas GK, Sirbu CA, Authier FJ; European Network on ME/CFS (EUROMENE). Myalgic encephalomyelitis/chronic fatigue Syndrome (ME/CFS): Investigating care practices pointed out to disparities in diagnosis and treatment across European Union. PLoS One. 2019 Dec 5;14(12):e0225995. doi: 10.1371/journal.pone.0225995. eCollection 2019. https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0225995 (Full article)

Circulating levels of GDF15 in patients with myalgic encephalomyelitis/chronic fatigue syndrome

Abstract:

BACKGROUND: Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) is a debilitating condition characterised by fatigue and post-exertional malaise. Its pathogenesis is poorly understood. GDF15 is a circulating protein secreted by cells in response to a variety of stressors. The receptor for GDF15 is expressed in the brain, where its activation results in a range of responses. Among the conditions in which circulating GDF15 levels are highly elevated are mitochondrial disorders, where early skeletal muscle fatigue is a key symptom. We hypothesised that GDF15 may represent a marker of cellular stress in ME/CFS.

METHODS: GDF15 was measured in serum from patients with ME/CFS (n = 150; 100 with mild/moderate and 50 with severe symptoms), “healthy volunteers” (n = 150) and a cohort of patients with multiple sclerosis (n = 50).

RESULTS: Circulating GDF15 remained stable in a subset of ME/CFS patients when sampled on two occasions ~ 7 months (IQR 6.7-8.8) apart, 720 pg/ml (95% CI 625-816) vs 670 pg/ml (95% CI 598-796), P = 0.5. GDF15 levels were 491 pg/ml in controls (95% CI 429-553), 546 pg/ml (95% CI 478-614) in MS patients, 560 pg/ml (95% CI 502-617) in mild/moderate ME/CFS patients and 602 pg/ml (95% CI 531-674) in severely affected ME/CFS patients. Accounting for potential confounders, severely affected ME/CFS patients had GDF15 concentrations that were significantly increased compared to healthy controls (P = 0.01). GDF15 levels were positively correlated (P = 0.026) with fatigue scores in ME/CFS.

CONCLUSIONS: Severe ME/CFS is associated with increased levels of GDF15, a circulating biomarker of cellular stress that appears which stable over several months.

Source: Melvin A, Lacerda E, Dockrell HM, O’Rahilly S, Nacul L. Circulating levels of GDF15 in patients with myalgic encephalomyelitis/chronic fatigue syndrome. J Transl Med. 2019 Dec 4;17(1):409. doi: 10.1186/s12967-019-02153-6. https://www.ncbi.nlm.nih.gov/pubmed/31801546

Transient receptor potential melastatin 2 channels are overexpressed in myalgic encephalomyelitis/chronic fatigue syndrome patients

Abstract:

BACKGROUND: Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) is hallmarked by a significant reduction in natural killer (NK) cell cytotoxicity, a mechanism tightly regulated by calcium (Ca2+). Interestingly, interleukin-2 (IL-2) increases NK cell cytotoxicity. Transient receptor potential melastatin 2 (TRPM2) ion channels are fundamental for Ca2+ signalling in NK cells. This pilot investigation aimed to characterise TRPM2 and CD38 surface expression in vitro on NK cells in ME/CFS patients. This investigation furthermore examined the pharmaceutical effect of 8-bromoadenosine phosphoribose (8-Br-ADPR) and N6-Benzoyladenosine-3′,5′-cyclic monophosphate (N6-Bnz-cAMP) on TRPM2 and CD38 surface expression and NK cell cytotoxicity between ME/CFS and healthy control (HC) participants.

METHODS: Ten ME/CFS patients (43.45 ± 12.36) and 10 HCs (43 ± 12.27) were age and sex-matched. Isolated NK cells were labelled with fluorescent antibodies to determine baseline and drug-treated TRPM2 and CD38 surface expression on NK cell subsets. Following IL-2 stimulation, NK cell cytotoxicity was measured following 8-Br-ADPR and N6-Bnz-cAMP drug treatments by flow cytometry.

RESULTS: Baseline TRPM2 and CD38 surface expression was significantly higher on NK cell subsets in ME/CFS patients compared with HCs. Post IL-2 stimulation, TRPM2 and CD38 surface expression solely decreased on the CD56DimCD16+ subset. 8-Br-ADPR treatment significantly reduced TRPM2 surface expression on the CD56BrightCD16Dim/- subset within the ME/CFS group. Baseline cell cytotoxicity was significantly reduced in ME/CFS patients, however no changes were observed post drug treatment in either group.

CONCLUSION: Overexpression of TRPM2 on NK cells may function as a compensatory mechanism to alert a dysregulation in Ca2+ homeostasis to enhance NK cell function in ME/CFS, such as NK cell cytotoxicity. As no improvement in NK cell cytotoxicity was observed within the ME/CFS group, an impairment in the TRPM2 ion channel may be present in ME/CFS patients, resulting in alterations in [Ca2+]i mobilisation and influx, which is fundamental in driving NK cell cytotoxicity. Differential expression of TRPM2 between NK cell subtypes may provide evidence for their role in the pathomechanism involving NK cell cytotoxicity activity in ME/CFS.

Source: Balinas C, Cabanas H, Staines D, Marshall-Gradisnik S. Transient receptor potential melastatin 2 channels are overexpressed in myalgic encephalomyelitis/chronic fatigue syndrome patients. J Transl Med. 2019 Dec 3;17(1):401. doi: 10.1186/s12967-019-02155-4. https://www.ncbi.nlm.nih.gov/pubmed/31796045

Myalgic encephalomyelitis and chronic fatigue syndrome case definitions: effects of requiring a substantial reduction in functioning

Abstract:

BACKGROUND: Current case definitions for myalgic encephalomyelitis (ME) and chronic fatigue syndrome (CFS) require an individual to report a ‘substantial reduction’ in activity levels, when compared to premorbid functioning. However, little guidance is provided on how to measure these reductions, as well as what level of reduction should be deemed ‘substantial,’ leading to inconsistencies in how this criterion is applied across research settings.

PURPOSE: The current study examined the influence of substantial reduction criterion on case definitions.

METHOD: The current study analyzed an international convenience sample of 1002 individuals with ME or CFS, 53 healthy controls, and 260 controls with other chronic illnesses.

RESULTS: Findings indicated that the utility of the substantial reduction criterion varied by case definition, with more stringent case definitions not needing this criterion to identify cases.

CONCLUSION: These results suggest that the requirement of a substantial reduction in functioning may be redundant when case definitions specify that individuals must endorse a set of core symptoms at specified frequency and severity levels.

Source: Scartozzi S, Sunnquist M, Jason LA. Myalgic encephalomyelitis and chronic fatigue syndrome case definitions: effects of requiring a substantial reduction in functioning. Fatigue. 2019;7(2):59-68. doi: 10.1080/21641846.2019.1600825. Epub 2019 Apr 1. https://www.ncbi.nlm.nih.gov/pubmed/31788347