Activation of human herpesviruses 6 and 7 in patients with chronic fatigue syndrome

Abstract:

BACKGROUND: Human herpesvirus 6 (HHV-6) and 7 (HHV-7) have been suggested as possible triggering agents for chronic fatigue syndrome(CFS).

OBJECTIVES: To determine the possible association of HHV-6 and HHV-7 infections with CFS.

STUDY DESIGN: The prevalence of latent/persistent and active viral infections by nPCR, characteristic of HHV-6 variants using restriction endonuclease analysis and changes of lymphocyte subsets in peripheral blood by laser flow-cytometry in 17 CFS patients was examined. In addition, 12 patients with unexplained chronic fatigue and 20 blood donors (BD) were studied.

RESULTS: No difference in prevalence of latent/persistent single viral infections between the patients and BD was found but dual infection rate was significantly higher in CFS patients. Active HHV-6 and dual (HHV-6 + HHV-7) infections were detected in CFS patients only and frequency of HHV-7 reactivation was also significantly higher in these patients. HHV-6 variant B was predominant in CFS patients (12/13). The changes of immunological parameters in CFS patients with active dual infection were characterized by significant decrease of CD3+ and CD4+ T cells, significant increase of CD95+ cells and decrease of CD4+/CD8+ ratio.

CONCLUSIONS: HHV-6 and HHV-7 may be involved in the pathogenesis of CFS and reactivation of both viruses may provoke changes in the phenotype of circulating lymphocytes.

 

Source: Chapenko S, Krumina A, Kozireva S, Nora Z, Sultanova A, Viksna L, Murovska M. Activation of human herpesviruses 6 and 7 in patients with chronic fatigue syndrome. J Clin Virol. 2006 Dec;37 Suppl 1:S47-51. https://www.ncbi.nlm.nih.gov/pubmed/17276369

 

Lymphocyte subset differences in patients with chronic fatigue syndrome, multiple sclerosis and major depression

Abstract:

Chronic fatigue syndrome (CFS) is a heterogeneous disorder of unknown aetiology characterized by debilitating fatigue, along with other symptoms, for at least 6 months. Many studies demonstrate probable involvement of the central and autonomic nervous system, as well as a state of generalized immune activation and selective immune dysfunction in patients with CFS. The aim of this study was to compare the lymphocyte subsets of patients with chronic fatigue syndrome to those of patients with major depression and multiple sclerosis as well as those of healthy control subjects.

No differences were found in total numbers of T cells, B cells or natural killer (NK) cells. However, differences were found in T, B and NK cell subsets. Patients with major depression had significantly fewer resting T (CD3(+)/CD25(-)) cells than the other groups. Patients with major depression also had significantly more CD20(+)/CD5(+) B cells, a subset associated with the production of autoantibodies.

Compared to patients with multiple sclerosis, patients with CFS had greater numbers of CD16(+)/CD3(-) NK cells. Further study will be required to determine whether these alterations in lymphocyte subsets are directly involved in the pathophysiology of these disorders, or are secondary effects of the causal agent(s).

 

Source: Robertson MJ, Schacterle RS, Mackin GA, Wilson SN, Bloomingdale KL, Ritz J, Komaroff AL. Lymphocyte subset differences in patients with chronic fatigue syndrome, multiple sclerosis and major depression. Clin Exp Immunol. 2005 Aug;141(2):326-32. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1809442/ (Full article)

 

Immunological variables mediate cognitive dysfunction in gulf war veterans but not civilians with chronic fatigue syndrome

Abstract:

We explored the relationship between a set of immunological variables and a set of cognitive and functional status measures and a diagnosis of chronic fatigue syndrome (CFS) in civilians and veterans using various regression and factor analytic methods.

Our approach emphasized the extraction of a few distinct factors in order to limit statistical problems associated with doing large numbers of multiple comparisons. This approach led to our finding cytokine data grouping into type 1 and type 2 clusters. A type 2 cluster plus a T and B cell factor predicted CFS caseness for Gulf War veterans but not for civilians with CFS. When a cognitive variable, reaction time, was added into the model, both immunological factors lost statistical significance; this indicates that the cognitive variable reaction time moderated the effects of the immunological factors in predicting patient status.

We did a similar analysis on the roles of the immunological and cognitive variables in functional status using SF-36 data. Higher levels of these same two immunological factors predicted poorer general health as well as poorer physical and social functioning in Gulf War veterans but not in civilians with CFS. When the reaction time factor was added, only the lymphocyte factor remained significant. This implies that lymphocytes are directly related to functional status in Gulf War veterans with CFS, but the Th2 factor produces its effect on functional status via changes in cognitive abilities.

Copyright 2002 S. Karger AG, Basel

 

Source: Brimacombe M, Zhang Q, Lange G, Natelson B. Immunological variables mediate cognitive dysfunction in gulf war veterans but not civilians with chronic fatigue syndrome. Neuroimmunomodulation. 2002-2003;10(2):93-100. http://www.ncbi.nlm.nih.gov/pubmed/12372983

 

Increased production of interleukin-6 by adherent and non-adherent mononuclear cells during ‘natural fatigue’ but not following ‘experimental fatigue’ in patients with chronic fatigue syndrome

Abstract:

In an investigator-blinded study, adherent (monocytes) and non-adherent cells (lymphocytes) from patients with chronic fatigue syndrome (CFS) were examined on two separate occasions (when feeling ‘fatigued’ and when feeling ‘rested’) for in vitro spontaneous, phytohemagglutinin- (PHA, for lymphocytes), and lipopolysaccharide- (LPS, for monocytes) induced production of IL-6 by ELISA assay.

A group of CFS patients and controls were also subjected to exercise-induced fatigue (‘experimental fatigue’) and IL-6 production was compared, in a double-blinded manner, prior to and following induction of fatigue.

A significant increase in spontaneous, PHA- and LPS-induced IL-6 secretion by both lymphocytes and monocytes was observed in CFS patients during ‘natural fatigue’ as compared to during state. However, no such changes in IL-6 production were observed during ‘experimental fatigue’.

These data suggest a role of IL-6 in natural symptomatology and perhaps in the pathogenesis of CFS. In addition, the data demonstrate that laboratory-induced fatigue (experimental fatigue) may not be a good model to study immunological changes in CFS; immunological parameters should be studied in a longitudinal manner during the natural course of the disease.

 

Source: Gupta S, Aggarwal S, Starr A. Increased production of interleukin-6 by adherent and non-adherent mononuclear cells during ‘natural fatigue’ but not following ‘experimental fatigue’ in patients with chronic fatigue syndrome. Int J Mol Med. 1999 Feb;3(2):209-13. http://www.ncbi.nlm.nih.gov/pubmed/9917531

 

Lymphocyte subsets, apoptosis, and cytokines in patients with chronic fatigue syndrome

Abstract:

Whether immunologic abnormalities correlate with fatigue severity and functional impairment in chronic fatigue syndrome (CFS) was investigated. Blood mononuclear cells were immunophenotyped and circulating ex vivo-produced cytokines were measured in 76 CFS patients and 69 healthy matched controls. Expression of CD11b on CD8 cells was significantly decreased in CFS patients. However, the previously reported increased expression of CD38 and HLA-DR was not confirmed. There was no obvious difference in apoptosis in leukocyte cultures, circulating cytokines, and ex vivo production of interleukin (IL)-1 alpha and IL-1 receptor antagonist. Endotoxin-stimulated ex vivo production of tumor necrosis factor-alpha and IL-beta was significantly lower in CFS. The immunologic test results did not correlate with fatigue severity or psychologic well-being was measured by Checklist Individual Strength, Beck Depression Inventory, and Sickness Impact Profile. Thus, these immunologic tests cannot be used as diagnostic tools in individual CFS patients.

 

Source: Swanink CM, Vercoulen JH, Galama JM, Roos MT, Meyaard L, van der Ven-Jongekrijg J, de Nijs R, Bleijenberg G, Fennis JF, Miedema F, van der Meer JW. Lymphocyte subsets, apoptosis, and cytokines in patients with chronic fatigue syndrome. J Infect Dis. 1996 Feb;173(2):460-3. http://jid.oxfordjournals.org/content/173/2/460.long (Full article)

 

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

 

Chronic Fatigue Syndrome: Do herbs or homeopathy help?

Abstract:

To determine the effect of certain herbal and homeopathic preparations on symptoms, lymphocyte markers, and cytotoxic function of the lymphocytes in patients with chronic fatigue syndrome, we studied six outpatients diagnosed with the disease by their family physicians. Patients were given herbal and homeopathic preparations after a 3-week symptom-recording period. After treatment, symptoms were again recorded. Blood samples were taken before and after treatment. None of the values showed any significant change after treatment.

 

Source: Leyton E, Pross H. Chronic Fatigue Syndrome: Do herbs or homeopathy help? Can Fam Physician. 1992 Sep;38:2021-6. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2145466/ (Full article)

 

A comprehensive immunological analysis in chronic fatigue syndrome

Abstract:

A detailed analysis of cell-mediated and antibody-mediated immunity was performed in 20 CDC-defined patients with chronic fatigue syndrome (CFS) and 20 age- and sex-matched healthy controls.

CD3+, CD4+, CD8+, and CD20+ lymphocytes were comparable in two groups. Natural killer cells as defined by CD16, CD56 and CD57 antigens were significantly reduced in CFS. A significant increase in the proportions of CD4+ ICAM 1+ T cells was observed in CFS. Monocytes from CFS displayed increased density (as determined by mean fluorescence channel numbers) of intercellular adhesion molecule 1 (ICAM-1) and lymphocyte function associated antigen 1 (LFA-1), but showed decreased enhancing response to recombinant interferon-gamma in vitro.

The lymphocyte DNA synthesis in response to phytohaemoglobulin (PHA), Concanavalin A (Con A) and pokeweed mitogen (PWM) was normal but the response to soluble antigens was significantly reduced. Serum IgM, IgG, IgA, and IgG subclasses were normal. In vivo specific antibody response to pneumococcus vaccine was depressed in CFS.

Forty percent of patients showed titres of anti-human herpes virus 6 (anti-HHV-6) antibody higher than that in the controls (greater than or equal to 1/80). These data suggest immunological dysfunction in patients with chronic fatigue syndrome. The significance of these observations is discussed.

 

Source: Gupta S, Vayuvegula B. A comprehensive immunological analysis in chronic fatigue syndrome. Scand J Immunol. 1991 Mar;33(3):319-27. http://www.ncbi.nlm.nih.gov/pubmed/1849315

 

Epidemic myalgic encephalomyelitis

The letter below, “Epidemic myalgic encephalomyelitis,” was published in the British Medical Journal in 1978. In it, the authors maintain that ME is an organic illness that exists as a distinct clinical entity with recognizable signs and symptoms. The authors propose that the cause may be “a persistent viral infection.

 

Epidemic myalgic encephalomyelitis

Outbreaks of the paralytic disease known as epidemic myalgic encephalomyelitis have puzzled doctors all over the world in the past 30 years. One of the best known of these epidemics was that at the Royal Free Hospital in London in 1955, which affected more than 300 people. (1) Most outbreaks tend to occur in the summer, young adults are predominantly affected, and the incidence is higher in women. The evidence suggests that infection is spread by personal contact, and young hospital personnel seem particularly at risk. The features common to every epidemic include headache, unusual muscular pains (which may be severe), lymphadenopathy-often of the posterior cervical lymph nodes-and low-grade fever.(2, 3) In a minority of cases frank neurological signs can be detected by careful clinical examination: there may be nystagmus, diplopia, myoclonus, bulbar weakness, motor weakness, increased or decreased tendon reflexes, disturbances of the sphincters, and extensor plantar responses.(2-7) Fasciculations, cranial nerve lesions, and extrapyramidal signs have also been reported. Most patients complain of paraesthesiae, and sensory loss is common.”(4) One characteristic feature of the disease is exhaustion, any effort producing generalised fatigue. Often there are psychiatric abnormalities, especially emotional lability and lack of concentration.(1- 3, 4) The clinical outcome may take any of three courses: some patients recover completely, some follow a relapsing course, and some are permanently incapacitated.(3)

At a symposium held recently at the Royal Society of Medicine to discuss the disease and plan research there was clear agreement that myalgic encephalomyelitis is a distinct nosological entity. Other terms that have been used to describe the disease were rejected as unsatisfactory for various reasons: the cardinal clinical features show that the disorder is an encephalomyelitis; “Iceland disease” is not specific enough; and “neuromyasthenia” suggests a relation to myasthenia gravis whereas the muscle fatigability is different, as are the electrophysiological findings.(8) Indeed, the exhaustion and tiredness are similar to that described by patients with multiple sclerosis.(9) From the patient’s point of view the designation benign is also misleading, since the illness may be devastating. Originally the term was used because no deaths had been recorded from myalgic encephalomyelitis. Two patients who had had the disease have now been examined post mortem: one was found to have multiple sclerosis. The adjective epidemic is correct, since most cases occur in an epidemic, but the disease may be endemic, and sporadic cases may occur. (10-12)

Some authors have attempted to dismiss this disease as hysterical, (13) but the evidence now makes such a tenet unacceptable. Some purely psychiatric symptoms may well occur, particularly in patients entering the chronic phase. No doubt, too, in an epidemic some hysterical persons will simulate the symptoms of the disease. Nevertheless, the organic basis is clear-from the finding that the putative agent can be transferred to monkeys(14); the detection of an increased urinary output of creatine2 (15); the persistent finding of abnormal lymphocytes in the peripheral blood of some patients (16); the presence of lymphocytes and an increased protein concentration in the cerebrospinal fluid of occasional patients (3); and the neurological findings. At this symposium more evidence was produced to support the organic nature of the disease. Increased serum concentrations of lactic dehydrogenases and transaminases have been found in several patients examined during the acute attack. In a recent outbreak in London immunological studies showed a high incidence of serum anticomplementary activity and the presence of ill-defined aggregates on electron microscopy of acute-phase sera.(17) A perplexing finding, suggesting the possibility of a persistent virus infection, was the ability of lymphocytes from patients to proliferate and survive in vitro for up to 19 weeks. The results of electroencephalographic studies were also stated to be abnormal, confirming other reports. (10)

We still know nothing about the nature and cause of epidemic myalgic encephalomyelitis, but outbreaks are still occurring. Future epidemics should be studied by a collaborative team of neurologists, epidemiologists, virologists, and immunologists. Its findings would be important not only for the study of epidemic myalgic encephalomyelitis but also for other neurological disorders, including multiple sclerosis.

1 British Medical Journal, 1957, 2, 895.

2 White, D N, and Burtch, R B, Neurology, 1954, 4, 506.

3 Acheson, E D, American Journal of Medicine, 1959, 26, 569.

4 Gilliam, A G, Epidemiological Study of an Epidemic, Public Health Bulletin, No 240. US Public Health Service, Washington, 1938.

5 Acheson, E D, Lancet, 1955, 2, 394.

6 Pellew, R A A, Medical Journal of Australia, 1951, 1, 944.

7 Hill, R C J, South African Medical Journal, 1955, 29, 344.

8 Richardson, A T, Annals of Physical Medicine, 1956, 3, 81.

9 McAlpine, D, Compston, N D, and Lumsden, C E, Multiple Sclerosis, chap 5. Edinburgh and London, Livingstone, 1955. ”

10 Ramsay, A M, and O’Sullivan, E, Lancet, 1956, 1, 761.

11 Jelinek, J E, Lancet, 1956, 2, 494.

12 Ramsay, A M, Lancet, 1957, 2, 1196.

13 McEvedey, C P, and Beard, A W, British Medical Journal, 1970, 1, 7.

14 Pellew, R A A, and Miles, J A R, Medical Journal of Australia, 1955, 2, 480.

15 Albrecht, R M, Oliver, V L, and Poskanzer, D C, Journal of the American Medical Association, 1964, 187, 904.

16 Wallis, A L, MD Thesis, Edinburgh University, 1957.

17 Dillon, M J, et al, British Medical Journal, 1974, 1, 301.

 

Source: BRITISH MEDICAL JOURNAL 3 JUNE 1978 1436-1437

You can read and download a PDF file of the letter at:  http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1604957/?page=1