Infection Elicited Autoimmunity and Myalgic Encephalomyelitis/Chronic Fatigue Syndrome: An Explanatory Model

Abstract:

Myalgic encephalomyelitis (ME) often also called chronic fatigue syndrome (ME/CFS) is a common, debilitating, disease of unknown origin. Although a subject of controversy and a considerable scientific literature, we think that a solid understanding of ME/CFS pathogenesis is emerging. In this study, we compiled recent findings and placed them in the context of the clinical picture and natural history of the disease.

A pattern emerged, giving rise to an explanatory model. ME/CFS often starts after or during an infection. A logical explanation is that the infection initiates an autoreactive process, which affects several functions, including brain and energy metabolism. According to our model for ME/CFS pathogenesis, patients with a genetic predisposition and dysbiosis experience a gradual development of B cell clones prone to autoreactivity. Under normal circumstances these B cell offsprings would have led to tolerance. Subsequent exogenous microbial exposition (triggering) can lead to comorbidities such as fibromyalgia, thyroid disorder, and orthostatic hypotension.

A decisive infectious trigger may then lead to immunization against autoantigens involved in aerobic energy production and/or hormone receptors and ion channel proteins, producing postexertional malaise and ME/CFS, affecting both muscle and brain. In principle, cloning and sequencing of immunoglobulin variable domains could reveal the evolution of pathogenic clones. Although evidence consistent with the model accumulated in recent years, there are several missing links in it. Hopefully, the hypothesis generates testable propositions that can augment the understanding of the pathogenesis of ME/CFS.

Source: Jonas Blomberg, Gerhard Gottfries, Amal Elfaitouri, Muhammad Rizwan and Anders Rosén. Infection Elicited Autoimmunity and Myalgic Encephalomyelitis/Chronic Fatigue Syndrome: An Explanatory Model. Hypothesis and Theory Article, Front. Immunol., 15 February 2018 | https://doi.org/10.3389/fimmu.2018.00229 (Full article)

On chronic fatigue syndrome and nosological categories

Abstract:

Chronic fatigue syndrome (CFS) is a heterogeneous disease which presents with pronounced disabling fatigue, sleep disturbances, and cognitive impairment that negatively affects patients’ functional capability. CFS remains a poorly defined entity and its etiology is still in question. CFS is neither a novel diagnosis nor a new medical condition. From as early as the eighteenth century, a constellation of perplexing symptoms was observed that resembled symptoms of CFS. Commencing with “febricula” and ending with CFS, many names for the disease were proposed including neurocirculatory asthenia, atypical poliomyelitis, Royal Free disease, effort syndrome, Akureyri disease, Tapanui disease, chronic Epstein-Barr virus syndrome, and myalgic encephalitis. To date, it remains unclear whether CFS has an autoimmune component or is a condition that precedes a full-blown autoimmune disease.

Research suggests that CFS may overlap with other diseases including postural orthostatic tachycardia syndrome (POTS), autoimmune syndrome induced by adjuvants (ASIA), and Sjögren’s syndrome. Additionally, it has been postulated that the earliest manifestations of some autoimmune diseases can present with vague non-specific symptoms similar to CFS. Sometimes only when exposed to a secondary stimulus (e.g., antigen) which could accelerate the natural course of the disease would an individual develop the classic autoimmune disease. Due to the similarity of symptoms, it has been postulated that CFS could simply be an early manifestation of an autoimmune disease. This paper will provide a historical background review of this disease and a discussion of CFS as an entity overlapping with multiple other conditions.

Source: Sharif K, Watad A, Bragazzi NL, Lichtbroun M, Martini M, Perricone C, Amital H, Shoenfeld Y. On chronic fatigue syndrome and nosological categories. Clin Rheumatol. 2018 Feb 7. doi: 10.1007/s10067-018-4009-2. [Epub ahead of print] https://www.ncbi.nlm.nih.gov/pubmed/29417255

Do anorexia, irritable bowel syndrome, chronic fatigues share a common cause?

Irritable bowel syndrome, chronic fatigue syndrome and anorexia nervosa may all have a common origin according to researchers.

They speculate that all three disorders may be caused by antibodies to the body’s own nerve cells because of a mistake by the immune system following infection.

At the moment, the ultimate cause of these illnesses remains a mystery.

Writing in Medical Hypotheses, Dr Jim Morris from the University Hospitals of Morecambe Bay NHS Trust, Dr Sue Broughton and Dr Quenton Wessels from Lancaster University say current explanations are unsatisfactory.

“Psychological factors might be important, but are unconvincing as the primary or major cause.

“There might, for instance, be an increased incidence of physical and sexual abuse in childhood in those who go on to manifest functional disorders. It is easy to see how this could influence symptoms in adults but it stretches credulity to imagine abuse as the sole and sufficient cause of the functional disorder.”

It is already well known that women are more at increased risk of autoimmune disease especially ones in which antibodies to the body’s own cells are thought to play a role, like thyroid disease, pernicious anemia and myasthenia gravis.

The researchers said: “The female to male ratio in these conditions is of the order of 10. The female excess in Irritable Bowel Syndrome, Chronic Fatigue Syndrome and Anorexia Nervosa is equally extreme and therefore this fits with the idea that auto-antibodies to nerve cells could be part of the pathogenesis of these conditions.”

The formation of auto-antibodies is found mostly among women and increases with age, which could be why these disorders are more common in midlife. Even with anorexia, which reaches a peak at the age of 30, auto-antibodies have been found in the bodies of patients.

There are also links with infection in that the onset of IBS commonly follows an episode of infectious diarrhea while chronic fatigue syndrome can be triggered by infectious mononucleosis and viral hepatitis.

Even anorexia could be influenced by secretions from bacteria affecting the brain, triggering the production of antibodies which affect mood and motivation.

“Auto-antibodies acting on the (brain’s) limbic system could induce extremes of emotion including disgust and fear. These then become linked, in the minds of adolescent girls, to culturally determined ideas of what is, and what is not, the ideal body shape and size. It is then a small step for disgust and fear to be directed to food and obesity which the fashion industry currently demonizes.”

If their idea is proven, the researchers suggest that these disorders may be amenable to treatment using pooled immunoglobulin from the blood of healthy people, especially in severe cases of anorexia where life is threatened. It should also be possible to identify and eliminate from the gut the bacteria which are triggering auto-antibodies.

Journal Reference: J.A. Morris, S.J. Broughton, Q. Wessels. Microbes, molecular mimicry and molecules of mood and motivation. Medical Hypotheses, 2016; 87: 40 DOI:10.1016/j.mehy.2015.12.011

 

Source: Lancaster University. “Do anorexia, irritable bowel syndrome, chronic fatigues share a common cause?.” ScienceDaily. ScienceDaily, 25 April 2016. https://www.sciencedaily.com/releases/2016/04/160425100204.htm

 

Humoral Immunity Profiling of Subjects with Myalgic Encephalomyelitis Using a Random Peptide Microarray Differentiates Cases from Controls with High Specificity and Sensitivity

Abstract:

Myalgic encephalomyelitis (ME) is a complex, heterogeneous illness of unknown etiology. The search for biomarkers that can delineate cases from controls is one of the most active areas of ME research; however, little progress has been made in achieving this goal. In contrast to identifying biomarkers that are directly involved in the pathological process, an immunosignature identifies antibodies raised to proteins expressed during, and potentially involved in, the pathological process. Although these proteins might be unknown, it is possible to detect antibodies that react to these proteins using random peptide arrays.

In the present study, we probe a custom 125,000 random 12-mer peptide microarray with sera from 21 ME cases and 21 controls from the USA and Europe and used these data to develop a diagnostic signature. We further used these peptide sequences to potentially uncover the naturally occurring candidate antigens to which these antibodies may specifically react with in vivo.

Our analysis revealed a subset of 25 peptides that distinguished cases and controls with high specificity and sensitivity. Additionally, Basic Local Alignment Search Tool (BLAST) searches suggest that these peptides primarily represent human self-antigens and endogenous retroviral sequences and, to a minor extent, viral and bacterial pathogens.

 

Source: Singh S, Stafford P, Schlauch KA, Tillett RR, Gollery M, Johnston SA, Khaiboullina SF, De Meirleir KL, Rawat S, Mijatovic T, Subramanian K, Palotás A, Lombardi VC. Humoral Immunity Profiling of Subjects with Myalgic Encephalomyelitis Using a Random Peptide Microarray Differentiates Cases from Controls with High Specificity and Sensitivity. Mol Neurobiol. 2016 Dec 15. [Epub ahead of print] https://www.ncbi.nlm.nih.gov/pubmed/27981498

 

Nitrosative Stress, Hypernitrosylation, and Autoimmune Responses to Nitrosylated Proteins: New Pathways in Neuroprogressive Disorders Including Depression and Chronic Fatigue Syndrome

Abstract:

Nitric oxide plays an indispensable role in modulating cellular signaling and redox pathways. This role is mainly effected by the readily reversible nitrosylation of selective protein cysteine thiols. The reversibility and sophistication of this signaling system is enabled and regulated by a number of enzymes which form part of the thioredoxin, glutathione, and pyridoxine antioxidant systems.

Increases in nitric oxide levels initially lead to a defensive increase in the number of nitrosylated proteins in an effort to preserve their function. However, in an environment of chronic oxidative and nitrosative stress (O&NS), nitrosylation of crucial cysteine groups within key enzymes of the thioredoxin, glutathione, and pyridoxine systems leads to their inactivation thereby disabling denitrosylation and transnitrosylation and subsequently a state described as “hypernitrosylation.”

This state leads to the development of pathology in multiple domains such as the inhibition of enzymes of the electron transport chain, decreased mitochondrial function, and altered conformation of proteins and amino acids leading to loss of immune tolerance and development of autoimmunity. Hypernitrosylation also leads to altered function or inactivation of proteins involved in the regulation of apoptosis, autophagy, proteomic degradation, transcription factor activity, immune-inflammatory pathways, energy production, and neural function and survival.

Hypernitrosylation, as a consequence of chronically elevated O&NS and activated immune-inflammatory pathways, can explain many characteristic abnormalities observed in neuroprogressive disease including major depression and chronic fatigue syndrome/myalgic encephalomyelitis. In those disorders, increased bacterial translocation may drive hypernitrosylation and autoimmune responses against nitrosylated proteins.

 

Source: Morris G, Berk M, Klein H, Walder K, Galecki P, Maes M. Nitrosative Stress, Hypernitrosylation, and Autoimmune Responses to Nitrosylated Proteins: New Pathways in Neuroprogressive Disorders Including Depression and Chronic Fatigue Syndrome. Mol Neurobiol. 2016 Jun 23. [Epub ahead of print] https://www.ncbi.nlm.nih.gov/pubmed/27339878

 

Antibodies to β adrenergic and muscarinic cholinergic receptors in patients with Chronic Fatigue Syndrome

Abstract:

Infection-triggered disease onset, chronic immune activation and autonomic dysregulation in CFS point to an autoimmune disease directed against neurotransmitter receptors. Autoantibodies against G-protein coupled receptors were shown to play a pathogenic role in several autoimmune diseases.

Here, serum samples from a patient cohort from Berlin (n=268) and from Bergen with pre- and post-treatment samples from 25 patients treated within the KTS-2 rituximab trial were analysed for IgG against human α and β adrenergic, muscarinic (M) 1-5 acetylcholine, dopamine, serotonin, angiotensin, and endothelin receptors by ELISA and compared to a healthy control cohort (n=108).

Antibodies against β2, M3 and M4 receptors were significantly elevated in CFS patients compared to controls. In contrast, levels of antibodies against α adrenergic, dopamine, serotonin, angiotensin, and endothelin receptors were not different between patients and controls. A high correlation was found between levels of autoantibodies and elevated IgG1-3 subclasses, but not with IgG4. Further patients with high β2 antibodies had significantly more frequently activated HLA-DR+ T cells and more frequently thyreoperoxidase and anti-nuclear antibodies.

In patients receiving rituximab maintenance treatment achieving prolonged B-cell depletion, elevated β2 and M4 receptor autoantibodies significantly declined in clinical responder, but not in non-responder.

We provide evidence that 29.5% of patients with CFS had elevated antibodies against one or more M acetylcholine and β adrenergic receptors which are potential biomarkers for response to B-cell depleting therapy. The association of autoantibodies with immune markers suggests that they activate B and T cells expressing β adrenergic and M acetylcholine receptors. Dysregulation of acetylcholine and adrenergic signalling could also explain various clinical symptoms of CFS.

Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

 

Source: Loebel M, Grabowski P, Heidecke H, Bauer S, Hanitsch LG, Wittke K, Meisel C, Reinke P, Volk HD, Fluge Ø, Mella O, Scheibenbogen C. Antibodies to β adrenergic and muscarinic cholinergic receptors in patients with Chronic Fatigue Syndrome. Brain Behav Immun. 2016 Feb;52:32-9. doi: 10.1016/j.bbi.2015.09.013. Epub 2015 Sep 21. https://www.ncbi.nlm.nih.gov/pubmed/26399744

 

Attenuation of autoimmune responses to oxidative specific epitopes, but not nitroso-adducts, is associated with a better clinical outcome in Myalgic Encephalomyelitis/chronic fatigue syndrome

Abstract:

OBJECTIVES: There is evidence that inflammatory, oxidative and nitrosative stress (IO&NS) pathways participate in the pathophysiology of a subgroup of patients with Myalgic Encephalomyelitis/chronic fatigue syndrome (ME/CFS). Increased IgM-related autoimmune responses to oxidative specific epitopes (OSEs), including malondialdehyde (MDA), oleic acid and phosphatidyl inositol (Pi), and nitroso-(NO)-adducts, including NO-tryptophan (NOW), NO-arginine and NO-cysteinyl, are frequently observed in ME/CFS. Autoimmune responses in ME/CFS may be driven by increased bacterial translocation as measured by IgM and IgA responses to LPS of gram negative bacteria.

METHODS: The aim of this study is to examine whether IgM responses to OSEs and NO-adducts are related to a better outcome as measured by the Fibromyalgia and Fatigue Rating Scale (FF). 76 ME/CFS patients with initially abnormal autoimmune responses were treated with care-as-usual, including nutraceuticals with anti-IO&NS effects (NAIOS), such as L-carnitine, coenzyme Q10, taurine + lipoic acid, with or without curcumine + quercitine or N-acetyl-cysteine, zinc + glutamine.

RESULTS: We found that use of these NAIOS was associated with highly significant reductions in initially increased IgM-mediated autoimmune responses to OSEs and NO-adducts. A greater reduction in autoimmune responses to OSEs during intake of these NAIOS was associated with a lower FF score. Reductions in IgM responses to oleic acid, MDA and Pi, but not in any of the NO-adducts, were associated with reductions in severity of illness. These associations remained significant after adjusting for possible effects of increased bacterial translocation (leaky gut).

CONCLUSIONS: Our results show that autoimmune responses to OSEs are involved in the pathophysiology of ME/CFS and that these pathways are a new drug target in a subgroup of ME/CFS patients. Although hypernitrosylation and nitrosative stress play a role in ME/CFS, reductions in these pathways are not associated with lowered severity of illness. Randomized controlled trials with NAIOS should be carried out in the subgroup of ME/CFS patients with initially increased autoimmune responses to OSEs.

 

Source: Maes M, Leunis JC. Attenuation of autoimmune responses to oxidative specific epitopes, but not nitroso-adducts, is associated with a better clinical outcome in Myalgic Encephalomyelitis/chronic fatigue syndrome. Neuro Endocrinol Lett. 2014;35(7):577-85. https://www.ncbi.nlm.nih.gov/pubmed/25617880

 

Oxidative and Nitrosative Stress and Immune-Inflammatory Pathways in Patients with Myalgic Encephalomyelitis (ME)/Chronic Fatigue Syndrome (CFS)

Abstract:

Myalgic Encephalomyelitis (ME) / Chronic Fatigue Syndrome (CFS) has been classified as a disease of the central nervous system by the WHO since 1969. Many patients carrying this diagnosis do demonstrate an almost bewildering array of biological abnormalities particularly the presence of oxidative and nitrosative stress (O&NS) and a chronically activated innate immune system.

The proposal made herein is that once generated chronically activated O&NS and immune-inflammatory pathways conspire to generate a multitude of self-sustaining and self-amplifying pathological processes which are associated with the onset of ME/CFS. Sources of continuous activation of O&NS and immune-inflammatory pathways in ME/CFS are chronic, intermittent and opportunistic infections, bacterial translocation, autoimmune responses, mitochondrial dysfunctions, activation of the Toll-Like Receptor Radical Cycle, and decreased antioxidant levels.

Consequences of chronically activated O&NS and immune-inflammatory pathways in ME/CFS are brain disorders, including neuroinflammation and brain hypometabolism / hypoperfusion, toxic effects of nitric oxide and peroxynitrite, lipid peroxidation and oxidative damage to DNA, secondary autoimmune responses directed against disrupted lipid membrane components and proteins, mitochondrial dysfunctions with a disruption of energy metabolism (e.g. compromised ATP production) and dysfunctional intracellular signaling pathways. The interplay between all of these factors leads to self-amplifying feed forward loops causing a chronic state of activated O&NS, immune-inflammatory and autoimmune pathways which may sustain the disease.

 

Source: Morris G, Maes M. Oxidative and Nitrosative Stress and Immune-Inflammatory Pathways in Patients with Myalgic Encephalomyelitis (ME)/Chronic Fatigue Syndrome (CFS). Curr Neuropharmacol. 2014 Mar;12(2):168-85. doi: 10.2174/1570159X11666131120224653. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3964747/ (Full article)

 

Role of adaptive and innate immune cells in chronic fatigue syndrome/myalgic encephalomyelitis

Abstract:

Perturbations in immune processes are a hallmark of a number of autoimmune and inflammatory disorders. Chronic fatigue syndrome/myalgic encephalomyelitis (CFS/ME) is an inflammatory disorder with possible autoimmune correlates, characterized by reduced NK cell activity, elevations in regulatory T cells (Tregs) and dysregulation in cytokine levels. The purpose of this article is to examine innate and adaptive immune cell phenotypes and functional characteristics that have not been previously examined in CFS/ME patients.

Thirty patients with CFS/ME and 25 non-fatigued controls were recruited for this study. Whole blood samples were collected from all participants for the assessment of cell phenotypes, functional properties, receptors, adhesion molecules, antigens and intracellular proteins using flow cytometric protocols. The cells investigated included NK cells, dendritic cells, neutrophils, B cells, T cells, γδT cells and Tregs.

Significant changes were observed in B-cell subsets, Tregs, CD4(+)CD73(+)CD39(+) T cells, cytotoxic activity, granzyme B, neutrophil antigens, TNF-α and IFN-γ in the CFS/ME patients in comparison with the non-fatigued controls. Alterations in B cells, Tregs, NK cells and neutrophils suggest significant impairments in immune regulation in CFS/ME and these may have similarities to a number of autoimmune disorders.

 

Source: Brenu EW, Huth TK, Hardcastle SL, Fuller K, Kaur M, Johnston S, Ramos SB, Staines DR, Marshall-Gradisnik SM. Role of adaptive and innate immune cells in chronic fatigue syndrome/myalgic encephalomyelitis. Int Immunol. 2014 Apr;26(4):233-42. doi: 10.1093/intimm/dxt068. Epub 2013 Dec 16. http://intimm.oxfordjournals.org/content/26/4/233.long (Full article)

 

Epitopes of microbial and human heat shock protein 60 and their recognition in myalgic encephalomyelitis

Abstract:

Myalgic encephalomyelitis (ME, also called Chronic Fatigue Syndrome), a common disease with chronic fatigability, cognitive dysfunction and myalgia of unknown etiology, often starts with an infection. The chaperonin human heat shock protein 60 (HSP60) occurs in mitochondria and in bacteria, is highly conserved, antigenic and a major autoantigen.

The anti-HSP60 humoral (IgG and IgM) immune response was studied in 69 ME patients and 76 blood donors (BD) (the Training set) with recombinant human and E coli HSP60, and 136 30-mer overlapping and targeted peptides from HSP60 of humans, Chlamydia, Mycoplasma and 26 other species in a multiplex suspension array. Peptides from HSP60 helix I had a chaperonin-like activity, but these and other HSP60 peptides also bound IgG and IgM with an ME preference, theoretically indicating a competition between HSP60 function and antibody binding. A HSP60-based panel of 25 antigens was selected.

When evaluated with 61 other ME and 399 non-ME samples (331 BD, 20 Multiple Sclerosis and 48 Systemic Lupus Erythematosus patients), a peptide from Chlamydia pneumoniae HSP60 detected IgM in 15 of 61 (24%) of ME, and in 1 of 399 non-ME at a high cutoff (p<0.0001). IgM to specific cross-reactive epitopes of human and microbial HSP60 occurs in a subset of ME, compatible with infection-induced autoimmunity.

 

Source: Elfaitouri A, Herrmann B, Bölin-Wiener A, Wang Y, Gottfries CG, Zachrisson O, Pipkorn R, Rönnblom L, Blomberg J. Epitopes of microbial and human heat shock protein 60 and their recognition in myalgic encephalomyelitis. PLoS One. 2013 Nov 28;8(11):e81155. doi: 10.1371/journal.pone.0081155. ECollection 2013. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3842916/ (Full article)