Category: Immune System

Serum levels of lymphokines and soluble cellular receptors in primary Epstein-Barr virus infection and in patients with chronic fatigue syndrome

Abstract:

The immunopathology in primary Epstein-Barr virus (EBV) infections and in chronic fatigue syndrome was studied by examining serum levels of interleukins (IL) and of soluble T cell receptors in serum samples.

Serum samples were from patients during and 6 months after primary EBV-induced infectious mononucleosis and from patients with chronic fatigue syndrome and serologic evidence of EBV reactivation. Markers for T lymphocyte activation (soluble IL-2 and CD8) and for monocyte activation (neopterin) were significantly elevated during acute infectious mononucleosis but not in patients with chronic fatigue syndrome.

Interferon-alpha, IL-1 beta, and IL-6 levels were not significantly increased in any patient group but inferferon-gamma levels were significantly increased during the acute phase of infectious mononucleosis. The levels of IL-1 alpha were significantly higher than in controls both in patients with infectious mononucleosis and in those with chronic fatigue syndrome. In the latter, the lack of most markers for lymphocyte activation found in patients with infectious mononucleosis makes it less likely that EBV reactivation causes symptoms.

 

Source: Linde A, Andersson B, Svenson SB, Ahrne H, Carlsson M, Forsberg P, Hugo H, Karstorp A, Lenkei R, Lindwall A, et al. Serum levels of lymphokines and soluble cellular receptors in primary Epstein-Barr virus infection and in patients with chronic fatigue syndrome. J Infect Dis. 1992 Jun;165(6):994-1000. http://www.ncbi.nlm.nih.gov/pubmed/1316417

 

A chronic illness characterized by fatigue, neurologic and immunologic disorders, and active human herpesvirus type 6 infection

Abstract:

OBJECTIVE: To conduct neurologic, immunologic, and virologic studies in patients with a chronic debilitating illness of acute onset.

DESIGN: Cohort study with comparison to matched, healthy control subjects.

PATIENTS: We studied 259 patients who sought care in one medical practice; 29% of the patients were regularly bedridden or shut-in.

MAIN OUTCOME MEASURES: Detailed medical history, physical examination, conventional hematologic and chemistry testing, magnetic resonance imaging (MRI) studies, lymphocyte phenotyping studies, and assays for active infection of patients’ lymphocytes with human herpesvirus type 6 (HHV-6).

MAIN RESULTS: Patients had a higher mean (+/- SD) CD4/CD8 T-cell ratio than matched healthy controls (3.16 +/- 1.5 compared with 2.3 +/- 1.0, respectively; P less than 0.003). Magnetic resonance scans of the brain showed punctate, subcortical areas of high signal intensity consistent with edema or demyelination in 78% of patients (95% CI, 72% to 86%) and in 21% of controls (CI, 11% to 36%) (P less than 10(-9)). Primary cell culture of lymphocytes showed active replication of HHV-6 in 79 of 113 patients (70%; CI, 61% to 78%) and in 8 of 40 controls (20%; CI, 9% to 36%) (P less than 10(-8], a finding confirmed by assays using monoclonal antibodies specific for HHV-6 proteins and by polymerase chain reaction assays specific for HHV-6 DNA.

CONCLUSIONS: Neurologic symptoms, MRI findings, and lymphocyte phenotyping studies suggest that the patients may have been experiencing a chronic, immunologically mediated inflammatory process of the central nervous system. The active replication of HHV-6 most likely represents reactivation of latent infection, perhaps due to immunologic dysfunction. Our study did not directly address whether HHV-6, a lymphotropic and gliotropic virus, plays a role in producing the symptoms or the immunologic and neurologic dysfunction seen in this illness. Whether the findings in our patients, who came from a relatively small geographic area, will be generalizable to other patients with a similar syndrome remains to be seen.

Comment in:

The chronic fatigue syndrome controversy. [Ann Intern Med. 1992]

The chronic fatigue syndrome controversy. [Ann Intern Med. 1992]

 

Source: Buchwald D, Cheney PR, Peterson DL, Henry B, Wormsley SB, Geiger A, Ablashi DV, Salahuddin SZ, Saxinger C, Biddle R, et al. A chronic illness characterized by fatigue, neurologic and immunologic disorders, and active human herpesvirus type 6 infection. Ann Intern Med. 1992 Jan 15;116(2):103-13. http://www.ncbi.nlm.nih.gov/pubmed/1309285

 

Cell-mediated immunity in patients with chronic fatigue syndrome, healthy control subjects and patients with major depression

Abstract:

The chronic fatigue syndrome (CFS) is characterized by severe persistent fatigue and neuropsychiatric symptoms. It has been proposed that the abnormalities in cell-mediated immunity which have been documented in patients with CFS may be attributable to a clinical depression, prevalent in patients with this disorder.

Cell-mediated immune status was evaluated in patients with carefully defined CFS and compared with that of matched subjects with major depression (non-melancholic, non-psychotic) as well as healthy control subjects.

Patients with CFS demonstrated impaired lymphocyte responses to phytohaemagglutinin (PHA) stimulation, and reduced or absent delayed-type hypersensitivity (DTH) skin responses when compared either with subjects with major depression or with healthy control subjects (P less than 0.05 for each analysis).

Although depression is common in patients with CFS, the disturbances of cell-mediated immunity in this disorder differ in prevalence and magnitude from those associated with major depression. These observations strengthen the likelihood of a direct relationship between abnormal cell-mediated immunity and the etiology of CFS.

 

Source: Lloyd A, Hickie I, Hickie C, Dwyer J, Wakefield D. Cell-mediated immunity in patients with chronic fatigue syndrome, healthy control subjects and patients with major depression. Clin Exp Immunol. 1992 Jan;87(1):76-9. http://www.ncbi.nlm.nih.gov/pubmed/1733640

Note : You can read the full article here: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1554231/

 

Hypothesis: cytokines may be activated to cause depressive illness and chronic fatigue syndrome

Abstract:

Abnormalities in the regulation of the hypothalamo-pituitary-adrenal (HPA) axis are a well recognised feature of endogenous depression. The mechanism underlying this phenomenon remains obscure although there is strong evidence suggesting excessive CRH activity at the level of the hypothalamus.

We propose a novel hypothesis in which we suggest that the aetiological antecent to CRH hyperactivity is cytokine activation in the brain. It is now well established both that interleukins -1 and -6 are produced in a number of central loci and that cytokines are potent stimulators of the HPA axis.

Hence, we suggest that activation of IL-1 and IL-6 by specific mechanisms (such as neurotropic viral infection) in combination with the consequent CRH-41 stimulation, may (via their known biological effects) underly many of the features found in major depression and other related disorders, particularly where chronic fatigue is a prominent part of the symptom complex.

This theory has considerable heuristic value and suggests a number of experimental stratagems which may employed in order to confirm or reject it.

 

Source: Ur E, White PD, Grossman A. Hypothesis: cytokines may be activated to cause depressive illness and chronic fatigue syndrome. Eur Arch Psychiatry Clin Neurosci. 1992;241(5):317-22. http://www.ncbi.nlm.nih.gov/pubmed/1606197

 

Immune responsiveness in chronic fatigue syndrome

Comment on: Immune responsiveness in chronic fatigue syndrome. [Postgrad Med J. 1991]

 

Sir, The paper by Milton and colleagues (1) challenges the hypothesis that patients with postviral fatigue syndrome (myalgic encephalomyelitis) have a persisting viral infection along with consequent immune dysregulation. The protocol employed in the study suggests that their conclusions may not be valid.

Firstly, the 31 patients were selected from a group attending a ‘muscle clinic’ who complained of ‘unexplained chronic fatigue’. Of these only 15 had a clear history of a precipitating viral illness – a key diagnostic feature of postviral fatigue syndrome. Secondly, although other research groups have also demonstrated that raised levels of Coxsackie B virus IgG and IgM antibodies are not diagnostic of the syndrome, (2) these findings cannot be used to exclude the possibility of persisting viral infection within either muscle or the central nervous system.

As far as muscle is concerned, Gow and colleagues( 3) have recently detected enteroviral RNA sequences in muscle biopsies of 53% of patients with a well-defined postviral fatigue syndrome compared to 15% in a control group, and Archard et al. (4) have shown that this persisting enterovirus is poorly replicating.

Demonstrating the presence of persisting virus within the central nervous system is obviously far more difficult without autopsy material. However, Daugherty et al. (5) in America have published the results of MRI scans and cognitive function tests on 20 patients (with age and sex matched healthy controls) showing abnormalities consistent with an organic brain syndrome similar to that seen in patients who are positive for human immunodeficiency virus.

You can read the rest of this letter here: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2399327/pdf/postmedj00061-0069a.pdf

 

Source: Shepherd C. Immune responsiveness in chronic fatigue syndrome. Postgrad Med J. 1992 Jan;68(795):66-7. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2399327/

 

Immunology of postviral fatigue syndrome

Abstract:

Postviral fatigue syndrome is associated with persistent infection by a virus. The patient with the condition has failed to eliminate the virus in the usual time. There is little evidence of a deficient immune response by the patient as the explanation for the viral persistence, and it must be assumed that most of the explanation lies in down-regulation of virus expression in infected cells. The general symptomatology of postinfectious syndromes may be mediated by cytokines liberated as part of the infection. Part of the syndrome may also be due to local effects of virus infection in muscles or the central nervous system (CNS).

 

Source: Mowbray JF, Yousef GE. Immunology of postviral fatigue syndrome. Br Med Bull. 1991 Oct;47(4):886-94. http://www.ncbi.nlm.nih.gov/pubmed/1724405

 

Chronic fatigue syndrome: clinical condition associated with immune activation

Abstract:

There is much conflicting immunological and viral data about the causes of chronic fatigue syndrome (CFS); some findings support the notion that CFS may be due to one or more immune disorders that have resulted from exposure to an infectious agent.

In the present study, flow cytometry and several different recognising T, B, and natural killer (NK) cell populations as well as activation and cell adhesion antigens were used to study 147 individuals with CFS.

Compared with healthy controls, a reduced CD8 suppressor cell population and increased activation markers (CD38, HLA-DR) on CD8 cells were found. The differences were significant (p = 0.01) in patient with major symptoms of the disease. These immunological indices were not observed in 80 healthy individuals, in 22 contacts of CFS patients, or in 43 patients with other diseases.

No correlation of these findings in CFS patients with any known human viruses could be detected by serology. The findings suggest that immune activation is associated with many cases of CFS.

 

Source: Landay AL, Jessop C, Lennette ET, Levy JA. Chronic fatigue syndrome: clinical condition associated with . Lancet. 1991 Sep 21;338(8769):707-12. http://www.ncbi.nlm.nih.gov/pubmed/1679864

 

Clinical and pathogenetic observations on children with chronic mononucleosis

Abstract:

Epstein-Barr virus is seldom the causative agent of a prolonged atypical illness, known as chronic mononucleosis syndrome, characterized by a persistent pattern of clinical manifestations and by a defective immune response to specific viral antigens. This paper refers about 6 children for whom clinical and serological findings suggest the chronic Epstein-Barr virus infection. The authors believe that this chronic state might be explained by the unusual antibody pattern to EBV virus, with the persistent presence of anti-EA and the absence of anti-EBNA titers, expression of a reduced EBV-specific cytotoxic T cell activity.

 

Source: Cataldo F, Ammatuna P, Bellia L, Sammartano F, Violante M, Albeggiani A. Clinical and pathogenetic observations on children with chronic mononucleosis. Pediatr Med Chir. 1991 Sep-Oct;13(5):489-94. [Article in Italian] http://www.ncbi.nlm.nih.gov/pubmed/1664943

 

Altered cytokine release in peripheral blood mononuclear cell cultures from patients with the chronic fatigue syndrome

Abstract:

Chronic fatigue syndrome (CFS) is an idiopathic illness associated with a variety of immunologic abnormalities. To investigate potential pathogenetic mechanisms, we evaluated serum levels and peripheral blood mononuclear cell (PBMC) production of selected cytokines and immunoglobulins.

Serum bioactive transforming growth factor beta (TGF-beta) levels were higher (P less than 0.01) in patients with CFS (290 +/- 46 pg/mL) than in control subjects (104 +/- 18 pg/mL), but levels of other cytokines tested were not different. Lipopolysaccharide-stimulated release of interleukin 1 beta (IL-1 beta), IL-6, and tumor necrosis factor-alpha was increased (P less than 0.05) in PBMC cultures from patients with CFS versus control subjects; enhanced (P less than 0.01) IL-6 release to phytohemagglutinin was also observed.

In contrast, TGF-beta release in response to lipopolysaccharide was depressed (P less than 0.01) in PBMC cultures derived from patients with CFS. No differences in IL-2 and IL-4 or immunoglobulin production were observed.

The enhanced release of inflammatory cytokines by stimulated PBMC from patients with CFS suggests that these cells are primed for an increased response to immune stimuli. These data also suggest an association between abnormal regulation of TGF-beta production in vivo and in vitro with the immunologic consequence of CFS.

 

Source: Chao CC1, Janoff EN, Hu SX, Thomas K, Gallagher M, Tsang M, Peterson PK. Altered cytokine release in peripheral blood mononuclear cell cultures from patients with the chronic fatigue syndrome. Cytokine. 1991 Jul;3(4):292-8. http://www.ncbi.nlm.nih.gov/pubmed/1873478

 

Immune responsiveness in chronic fatigue syndrome

Abstract:

We have endeavoured to find immunological indications of chronic virus infection in patients with chronic fatigue syndrome (myalgic encephalomyelitis) and to investigate immune responsiveness to viruses in such patients in comparison with normal subjects and patients with muscular dystrophy.

Levels of circulating IgM immune complexes were elevated (above the 95% normal control range) in 10 (17%) of 58 patients with chronic fatigue syndrome, which was not significantly different from the normal controls or from dystrophy controls (by Mann Whitney U test). Levels of IgG complexes were only increased in 10% of patients. Lymphocyte proliferation in response to concanavalin A (Con A), assessed by increase in 3H-thymidine incorporation, did not differ between 14 patients and 18 normal subjects.

The proliferative response to Coxsackie B virus antigen did not differ between chronic fatigue patients and normal subjects when expressed either as an increase in counts or as a stimulation index. Adjustment of the counts in relation to the proliferation response to Con A, as an indication of the overall proliferative response of the cell preparation, did not reveal any hidden difference. IgM antibodies to Coxsackie B viruses were not found in any of 20 patients and in 1 of 20 dystrophy controls.

Significant levels of neutralizing antibodies to Coxsackie B viruses 1-5 were found in 6 out of 19 (32%) patients compared with 4 out of 17 (24%) dystrophy controls, which does not differ from currently expected normal incidence. Antibody titres to other respiratory viruses were also not notably different between the patient and control groups.

In conclusion we can find no evidence for a definable viral aetiology for the chronic fatigue syndrome, neither in terms of a persistent infection nor an altered ability to respond to virus.

Comment in: Immune responsiveness in chronic fatigue syndrome. [Postgrad Med J. 1992]

 

Source: Milton JD, Clements GB, Edwards RH. Immune responsiveness in chronic fatigue syndrome. Postgrad Med J. 1991 Jun;67(788):532-7. http://www.ncbi.nlm.nih.gov/pubmed/1656416

Note: You can read the full article here: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2398884/