Category: Immune System

Viral studies of chronic fatigue syndrome

Abstract:

Chronic fatigue syndrome (CFS) has many characteristics suggesting persistent fatigue following a viral illness. At least nine different RNA and DNA viruses have been considered to be associated with this disease, but none of these viruses has been found to be the etiologic agent. Immunologic studies have demonstrated activated CD8+ cells and reduced function of natural killer cells suggesting a host response to an infection that has led to persistent immune disorders. Some of the symptoms of CFS may be due to cytokines produced by this hyperactive immune response to a virus that is still present in the host or that has been eliminate but leaves abnormal immunologic sequelae. These possibilities offer directions for future studies of CFS and therapeutic approaches to this condition.

 

Source: Levy JA. Viral studies of chronic fatigue syndrome. Clin Infect Dis. 1994 Jan;18 Suppl 1:S117-20. http://www.ncbi.nlm.nih.gov/pubmed/8148437

 

The chronic fatigue syndrome

Abstract:

CFIDS (chronic fatigue and immune disfunction syndrome) is also known as CFS (chronic fatigue syndrome), CEBV (chronic Epstein-Barr virus), M.E. (myalgic encephalomyelitis), yuppie flu and by other names.

It is a complex illness characterized by incapacitating fatigue (experienced as exhaustion and extremely poor stamina), neurological problems and a constellation of symptoms that can resemble many disorders, including; mononucleosis, multiple sclerosis, fibromyalgia, AIDS-related complex (ARC) and autoimmune diseases such as lupus. These symptoms tend to wax and wane, but any often severely debilitating and may last for many months or years. All sections of the population (including children) are at risk, but women under 45 seem to be most susceptible.

The investigators suggest that CFIDS results from dysfunction of the immune system. The exact nature of this dysfunction is not yet well defined, but it can generally be viewed as an unregulated or overactive state which is responsible for most of the symptoms. There is also evidence of some immune suppression in CFIDS. None of the treatments is consistently satisfactory, but some may be helpful: psychotherapy, physiotherapy, exercise programs, acupunctures, small doses of antidepressants, etc.

 

Source: Artsimovich NG, Chugunov VS, Kornev AV, Ivanova TM, Chugunov AV, Oprishchenko MA. The chronic fatigue syndrome. Zh Nevrol Psikhiatr Im S S Korsakova. 1994;94(5):47-50. [Article in Russian] http://www.ncbi.nlm.nih.gov/pubmed/7900453

 

Chronic fatigue syndrome: immune dysfunction, role of pathogens and toxic agents and neurological and cardial changes

Abstract:

375 patients with chronic fatigue syndrome (CFS) were examined using a standardized questionnaire and subsequent interview on 11 risk factors and 45 symptoms. Additionally immunologic, serologic, toxicologic, neuroradiologic, neurophysiologic and cardiologic investigations were performed.

Immunologic tests showed cellular immunodeficiences particularly in functional regard (pathological lymphocyte stimulation in 50% of the patients, disorders of granulocyte function in 44%). Furthermore variable deviations were found in the lymphocyte subpopulations (CD3, CD4, CD8, CD19, DR, Leu 11 + 19).

In the humoral part tendencies to low IgG-3- and IgG-1-subclass-levels occurred (59% respectively 11% of the patients) also as decreases in complement system (CH50, C3, C4, C1-esterase-inhibitor). In the group of activation markers and cytokines 42% of the investigated patients had circulating immune complexes (CIC), 47% increases of tumor-necrosis-factor (TNF-a) and 21% increases of soluble interleukin-2-receptor (IL-2-R).

The increased occurrence of autoantibodies in the CFS-patients (specially antinuclear anti-bodies [ANA], microsomal thyroid antibodies) suggest, that CFS is associated with or the beginning of manifest autoimmune disease.

Under the pathogens 78% of the patients had a striking serological constellation of Epstein-Barr-Virus (EBV-EA positive, low EBNA-titers), in the HHV-6-Virus 47% showed increased antibody-titers. Tests on further herpes viruses and on Borreliae, Chlamydiae, Candida and Amoebae were positive in 8 to 36% of the examined patients. Furthermore there were found variable deficits of vitamins and trace elements also as hormonal disturbances.

In 26% of the patients there were hints of pollutants (e.g. wood preservatives), in 32 patients blood-levels of pentachlorphenol (PCP) and gamma-hexachlorcyclohexan (γ-HCH, lindan) were measured, which showed vanable increases.

178 (83%) of 225 investigated patients showed disturbances of perfusion in cerebral SPECT imaging, 65 (29%) of 218 patients cerebral punctuate signal changes in cranial magnetic resonance imaging (MRI).

Neurophysiologic measurements (motor evoked potentials, MEP) showed in about 50% of 112 patients prolonged central motor conduction times. 62 patients were additionally investigated by myocardial SPECT-imaging, which was abnormal under exercise in 73%. Our data confirm the concept, that CFS must be considered as a complex psycho-neuro-immunological disorder.

 

Source: Hilgers A, Frank J. Chronic fatigue syndrome: immune dysfunction, role of pathogens and toxic agents and neurological and cardial changes. Wien Med Wochenschr. 1994;144(16):399-406.[Article in German] http://www.scopus.com/record/display.uri?eid=2-s2.0-0027940724&origin=inward&txGid=0

and http://www.ncbi.nlm.nih.gov/pubmed/7856214

 

 

Infection of natural killer cells by human herpesvirus 6

Abstract:

Natural killer (NK) cells are a functionally defined subset of non-T, non-B lymphocytes of bone marrow origin, which induce lysis of selected target cells, including neoplastic and virus-infected cells. The NK cell function provides an important mechanism of primary defence against viruses in vivo, as demonstrated by the occurrence of multiple herpesvirus infections in patients congenitally lacking NK cells.

Here we show that functionally competent CD3- NK clones can be productively infected by human herpesvirus 6 (HHV-6), a T-lymphotropic DNA virus that may play a role in the acquired immunodeficiency syndrome (AIDS) and in the chronic fatigue syndrome, two disorders associated with a defective NK cell activity.

The infection is cytopathic and induces de novo expression of CD4, an antigen not expressed within the NK lineage, thereby predisposing NK cells to infection by human immunodeficiency virus type 1 (HIV-1).

These results provide evidence that a herpesvirus can directly target and kill NK cells, a potential strategy to suppress the natural anti-viral immunity of the host.

 

Source: Lusso P, Malnati MS, Garzino-Demo A, Crowley RW, Long EO, Gallo RC. Infection of natural killer cells by human herpesvirus 6. Nature. 1993 Apr 1;362(6419):458-62. http://www.ncbi.nlm.nih.gov/pubmed/7681936

 

Fibromyalgia, sleep disorder and chronic fatigue syndrome

Abstract:

Various research studies show that the amalgam of disordered sleep physiology, chronic fatigue, diffuse myalgia, and cognitive and behavioural symptoms constitutes a non-restorative sleep syndrome that may follow a febrile illness, as in the chronic fatigue syndrome. Where rheumatic complaints are prominent such a constellation of disturbed sleep physiology and symptoms also characterizes the fibromyalgia disorder.

In contrast to the chronic fatigue syndrome, fibromyalgia is associated with a variety of initiating or perpetuating factors such as psychologically distressing events, primary sleep disorders (e.g. sleep apnoea, periodic limb movement disorder) and inflammatory rheumatic disease, as well as an acute febrile illness.

The chronic fatigue syndrome and fibromyalgia have similar disordered sleep physiology, namely an alpha rhythm disturbance (7.5-11 Hz) in the electroencephalogram (EEG) within non-rapid eye movement (NREM) sleep that accompanies increased nocturnal vigilance and light, unrefreshing sleep. Aspects of cytokine and cellular immune functions are shown to be related to the sleep-wake system.

The evidence suggests a reciprocal relationship of the immune and sleep-wake systems. Interference either with the immune system (e.g. by a viral agent or by cytokines such as alpha-interferon or interleukin 2) or with the sleeping-waking brain system (e.g. by sleep deprivation) has effects on the other system and will be accompanied by the symptoms of the chronic fatigue syndrome.

 

Source: Moldofsky H. Fibromyalgia, sleep disorder and chronic fatigue syndrome. Ciba Found Symp. 1993;173:262-71; discussion 272-9. http://www.ncbi.nlm.nih.gov/pubmed/8491102

 

Immunity and the pathophysiology of chronic fatigue syndrome

Abstract:

The pathophysiology of chronic fatigue syndrome (CFS) remains unknown. The syndrome often follows a recognized or presumed infection and the disorder may therefore result from a disordered immune response to a precipitating infection or antigenic challenge.

Abnormalities of both humoral and cellular immunity have been demonstrated in a substantial proportion of patients with CFS. The most consistent findings are of impaired lymphocyte responses to mitogen and reduced natural killer cell cytotoxicity. Cutaneous anergy and immunoglobulin G subclass deficiencies have also been found.

Further studies are needed examining cytokine levels in serum and cerebrospinal fluid, and cytokine production in vitro in patients with CFS. Interpretation of the findings of published studies of immunity is limited by probable heterogeneity in the patient groups studied, and by the lack of standardization and reproducibility in the assays used.

The pattern of abnormalities reported in immunological testing in patients with CFS is consistent with the changes seen during the resolving phases of acute viral infection. These data provide circumstantial support for the hypothesis that CFS results from a disordered immune response to an infection. Longitudinal studies of immunity in patients developing CFS after defined infectious illnesses will provide the best means of further examining this hypothesis.

 

Source: Lloyd AR, Wakefield D, Hickie I. Immunity and the pathophysiology of chronic fatigue syndrome. Ciba Found Symp. 1993;173:176-87; discussion 187-92. http://www.ncbi.nlm.nih.gov/pubmed/8491097

 

Enteroviruses and postviral fatigue syndrome

Abstract:

Postviral fatigue syndrome (PFS) occurs both in epidemics and sporadically. Many of the original epidemics were related to poliomyelitis outbreaks which either preceded or followed them.

The core clinical symptoms are always the same: severe fatigue made worse by exercise, myalgia, night sweats, atypical depression and excessive sleep. The other common symptoms include dysequilibrium disorders and irritable bowel syndrome.

We have detected enteroviral genome sequences in muscle biopsies from cases of PFS, using specific enteroviral oligonucleotide primers in the polymerase chain reaction (PCR). In addition, whole virus particles can be demonstrated in PCR-positive muscle, using solid-phase immuno-electron microscopy.

An increase in the number and size of muscle mitochondria was found in 70% of PFS cases, suggesting an abnormality in metabolic function. Evidence of hypothalamic dysfunction was present, particularly involving 5-hydroxytryptamine metabolism.

A putative model of PFS, based on persistent enteroviral infection in laboratory mice, revealed resolving inflammatory lesions in muscle with, however, a marked increase in the production of certain cytokines in the brain. This model may help to explain the pathogenesis of PFS.

 

Source: Behan PO, Behan WM, Gow JW, Cavanagh H, Gillespie S. Ciba Found Symp. 1993;173:146-54; discussion 154-9. http://www.ncbi.nlm.nih.gov/pubmed/8387908

 

Lymphocyte phenotype and function in the chronic fatigue syndrome

Abstract:

Lymphocytes of 18 patients meeting the Centers for Disease Control (CDC) case definition for the chronic fatigue syndrome (CFS), 10 similar, chronically fatigued patients not fully conforming to the CDC case definition, and 17 matched, healthy individuals were studied to determine the presence of abnormalities of peripheral cell phenotype and function.

Extensive phenotypic analyses of B- and T-cell subsets, natural killer (NK) cells, and macrophages were performed using single-, dual-, and three-color flow cytometry. Compared to controls, in CFS patients the percentage of CD4 T cells and CD4,CD45RA, or naive T cells, was reduced. The CD4,CD45RO, or memory T-cell, subset was numerically normal but expressed increased levels of adhesion markers (CD29, CD54, and CD58). CFS patient lymphocytes showed reduced proliferative responses to phytohemagglutinin, concanavalin A, and staphylococcal enterotoxin B. Lymphocytes from fatigue patients not meeting the CDC definition showed similar abnormalities.

These data indicate that peripheral T cells manifest an increased state of differentiation in CFS and related conditions. This may arise as a consequence of an underlying neuropsychiatric and/or neuroendocrine disorder or because of exposure to antigens or superantigens of an infectious agent.

 

Source: Straus SE, Fritz S, Dale JK, Gould B, Strober W. Lymphocyte phenotype and function in the chronic fatigue syndrome. J Clin Immunol. 1993 Jan;13(1):30-40. http://www.ncbi.nlm.nih.gov/pubmed/8095270

 

Plasma and cerebrospinal fluid monoamine metabolism in patients with chronic fatigue syndrome: preliminary findings

Abstract:

The syndrome of chronic fatigue, feverishness, diffuse pains, and other constitutional complaints, often precipitated by an acute infectious illness and aggravated by physical and emotional stressors, has a lengthy history in the medical literature.

The Centers for Disease Control (CDC) recently formulated a case definition, renaming the illness “chronic fatigue syndrome.” Nevertheless, there remain few biological data that can validate the existence of this syndrome as distinct from a wide variety of other, largely psychiatric disorders, and little understanding of its pathogenesis.

In the present study, basal plasma and cerebrospinal fluid levels of the monoamine metabolites, 3-methoxy-4-hydroxyphenylglycol (MHPG), 5-hydroxyindoleacetic acid (5-HIAA), and homovanillic acid (HVA) were determined in 19 patients meeting CDC research case criteria for chronic fatigue syndrome and in 17 normal individuals.

Patients with chronic fatigue syndrome showed a significant reduction in basal plasma levels of MHPG and a significant increase in basal plasma levels of 5-HIAA. Although the functional significance of these findings has not been definitively elucidated, they are compatible with the clinical presentation of a syndrome associated with chronic lethargy and fatigue, and with evidence of persistent immune stimulation, and lend support to the idea that chronic fatigue syndrome represents a clinical entity with potential biological specificity.

 

Source: Demitrack MA, Gold PW, Dale JK, Krahn DD, Kling MA, Straus SE. Plasma and cerebrospinal fluid monoamine metabolism in patients with chronic fatigue syndrome: preliminary findings. Biol Psychiatry. 1992 Dec 15;32(12):1065-77. http://www.ncbi.nlm.nih.gov/pubmed/1282370

 

Allergy among Japanese patients with chronic fatigue syndrome

Abstract:

Allergy is a common feature of patients with chronic fatigue syndrome (CFS). Because of this strong association, we attempted to explore the prevalence of allergies among Japanese patients with CFS.

Of the present 18 patients, 78% had allergies during their premorbid and/or postmorbid conditions. Their allergies were mainly cutaneous reactions including drug allergies and 43% of the patients had 2 or more allergic reactions.

In the case of a premorbid condition, allergies improved spontaneously after onset of CFS. Clinical manifestations of CFS, however, became worse during the period of an association with allergies.

Immunologic tests, including peripheral blood lymphocyte-subsets, blastogenesis, natural killer-cell functions and cytokine-assays, were not any correlation between both patients with and without allergies.

Source: Matsumoto Y, Ninomiya S. Allergy among Japanese patients with chronic fatigue syndrome. Arerugi. 1992 Dec;41(12):1722-5. [Article in Japanese] http://www.ncbi.nlm.nih.gov/pubmed/1290417