Category: Viruses

Cytomegalovirus, Epstein-Barr Virus and Human Herpesvirus 6 Infections in Patients with Myalgic Еncephalomyelitis/Chronic Fatigue Syndrom

Abstract:

Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) is a disabling multisystem chronic disease. The etiology and pathogenesis of ME/CFS are unknown. Infections of cytomegalovirus (CMV), Epstein-Barr virus (EBV) and human herpesvirus-6 (HHV-6) are suspected as etiological agents for ME/CFS. This study aims to estimate prevalence and type (active/latent) of EBV, CMV and HHV-6 infections in Bulgarian ME/CFS patients.

In the study were included 58 ME/CFS patients and 50 healthy controls. Virus-specific antibodies were detected by ELISA and viral genomic sequences in PBMCs and plasma samples – by nPCR. We did not observe any significant differences in virus specific IgG and IgM positivity rates between ME/CFS patients and control group. In ME/CFS plasma samples EBV DNA was found in 24.1%, CMV DNA – in 3.4% and HHV-6 DNA in 1.7% of samples. EBV DNA was detected in 4%, CMV and HHV-6 DNA were not found in plasma samples of controls. The frequency of viral genome detection in PBMCs of patients and controls was 74% vs 78% for CMV, 81% vs 84% for EBV, and 82.8% vs 82% for HHV-6. The difference in frequency of EBV active infection in ME/CFS and control group was statistically significant (p=0.0027). No ME/CFS and control individuals with active CMV and HHV-6 infection were observed.

In conclusion, our study using both serological and PCR-based techniques for distinguishing between active and latent infection, showed high rate of active EBV infection among ME/CFS patients indicating that at least in a subset of cases EBV is important factor for development of disease.

Source: Shikova E, Reshkova V, Kumanova А, Raleva S, Alexandrova D, Capo N, Murovska M; European Network on ME/CFS (EUROMENE). Cytomegalovirus, Epstein-Barr Virus and Human Herpesvirus 6 Infections in Patients with Myalgic Еncephalomyelitis/Chronic Fatigue Syndrome. J Med Virol. 2020 Mar 4. doi: 10.1002/jmv.25744. [Epub ahead of print] https://www.ncbi.nlm.nih.gov/pubmed/32129496

Antibodies to Human Herpesviruses in Myalgic Encephalomyelitis/Chronic Fatigue Syndrome Patients

Abstract:

Myalgic encephalomyelitis, also referred to as chronic fatigue syndrome (ME/CFS) is a debilitating disease characterized by myalgia and a sometimes severe limitation of physical activity and cognition. It is exacerbated by physical and mental activity. Its cause is unknown, but frequently starts with an infection. The eliciting infection (commonly infectious mononucleosis or an upper respiratory infection) can be more or less well diagnosed.

Among the human herpesviruses (HHV-1-8), HHV-4 (Epstein-Barr virus; EBV), HHV-6 (including HHV-6A and HHV-6B), and HHV-7, have been implicated in the pathogenesis of ME/CFS. It was therefore logical to search for serological evidence of past herpesvirus infection/reactivation in several cohorts of ME/CFS patients (all diagnosed using the Canada criteria).

Control samples were from Swedish blood donors. We used whole purified virus, recombinant proteins, and synthetic peptides as antigens in a suspension multiplex immunoassay (SMIA) for immunoglobulin G (IgG). The study on herpesviral peptides based on antigenicity with human sera yielded novel epitope information. Overall, IgG anti-herpes-viral reactivities of ME/CFS patients and controls did not show significant differences. However, the high precision and internally controlled format allowed us to observe minor relative differences between antibody reactivities of some herpesviral antigens in ME/CFS versus controls. ME/CFS samples reacted somewhat differently from controls with whole virus HHV-1 antigens and recombinant EBV EBNA6 and EA antigens.

We conclude that ME/CFS samples had similar levels of IgG reactivity as blood donor samples with HHV-1-7 antigens. The subtle serological differences should not be over-interpreted, but they may indicate that the immune system of some ME/CFS patients interact with the ubiquitous herpesviruses in a way different from that of healthy controls.

Source: Blomberg J, Rizwan M, Böhlin-Wiener A, Elfaitouri A, Julin P, Zachrisson O, Rosén A, Gottfries CG. Antibodies to Human Herpesviruses in Myalgic Encephalomyelitis/Chronic Fatigue Syndrome Patients. Front Immunol. 2019 Aug 14;10:1946. doi: 10.3389/fimmu.2019.01946. eCollection 2019 https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6702656/ (Full article)

Epstein-Barr virus (EBV) reactivation and therapeutic inhibitors

Abstract:

Epstein-Barr virus (EBV) is a ubiquitous human virus which infects almost all humans during their lifetime and following the acute phase, persists for the remainder of the life of the individual. EBV infects B lymphocytes leading to their immortalisation, with persistence of the EBV genome as an episome. In the latent phase, EBV is prevented from reactivating through efficient cytotoxic cellular immunity.

EBV reactivates (lytic phase) under conditions of psychological stress with consequent weakening of cellular immunity, and EBV reactivation has been shown to occur in a subset of individuals with each of a variety of cancers, autoimmune diseases, the autoimmune-like disease, chronic fatigue syndrome/myalgic encephalitis and under other circumstances such as being an inpatient in an intensive care unit.

Chronic EBV reactivation is an important mechanism in the pathogenesis of many such diseases, yet is rarely tested for in immunocompetent individuals. This review summarises the pathogenesis of EBV infection, EBV reactivation and its role in disease, and methods which may be used to detect it. Known inhibitors of EBV reactivation and replication are discussed, including drugs licensed for treatment of other herpesviruses, licensed or experimental drugs for various other indications, compounds at an early stage of drug development and nutritional constituents such as vitamins and dietary supplements.

Source: Kerr JR. Epstein-Barr virus (EBV) reactivation and therapeutic inhibitors. J Clin Pathol. 2019 Jul 17. pii: jclinpath-2019-205822. doi: 10.1136/jclinpath-2019-205822. [Epub ahead of print] https://www.ncbi.nlm.nih.gov/pubmed/31315893

Clinical symptoms and markers of disease mechanisms in adolescent chronic fatigue following Epstein-Barr virus infection: An exploratory cross-sectional study

Abstract:

INTRODUCTION: Acute Epstein-Barr virus (EBV) infection is a trigger of chronic fatigue (CF) and Chronic Fatigue Syndrome (CFS). The aim of this cross-sectional study was to explore clinical symptoms as well as markers of disease mechanisms in fatigued and non-fatigued adolescents 6 months after EBV-infection, and in healthy controls.

MATERIALS AND METHODS: A total of 200 adolescents (12-20 years old) with acute EBV infection were assessed 6 months after the initial infectious event and divided into fatigued (EBV CF+) and non-fatigued (EBV CF-) cases based on questionnaire score. The EBV CF+ cases were further sub-divided according to case definitions of CFS. In addition, a group of 70 healthy controls with similar distribution of sex and age was included. Symptoms were mapped with a questionnaire. Laboratory assays included EBV PCR and serology; detailed blood leukocyte phenotyping and serum high-sensitive C-reactive protein; and plasma and urine cortisol and catecholamines. Assessment of autonomic activity was performed with continuous, non-invasive monitoring of cardiovascular variables during supine rest, controlled breathing and upright standing. Differences between EBV CF+ and EBV CF- were assessed by simple and multiple linear regression adjusting for sex as well as symptoms of depression and anxiety. A p-value ≤ 0.05 was considered statistically significant. This study is part of the CEBA-project (Chronic fatigue following acute Epstein-Barr virus infection in adolescents).

RESULTS: The EBV CF+ group had significantly higher scores for all clinical symptoms. All markers of infection and most immune, neuroendocrine and autonomic markers were similar across the EBV CF+ and EBV CF- group. However, the EBV CF+ group had slightly higher serum C-reactive protein (0.48 vs 0.43 mg/L, p=0.031, high-sensitive assay), total T cell (CD3+) count (median 1573 vs 1481 x 106 cells/L, p=0.012), plasma norepinephrine (1420 vs 1113 pmol/L, p=0.01) and plasma epinephrine (363 vs 237 nmol/L, p=0.032); lower low-frequency:high frequency (LF/HF) ratio of heart rate variability at supine rest (0.63 vs 0.76, p=0.008); and an attenuated decline in LF/HF ratio during controlled breathing (-0.11 vs -0.25, p=0.002). Subgrouping according to different CFS diagnostic criteria did not significantly alter the results. Within the EBV CF+ group, there were no strong correlations between clinical symptoms and markers of disease mechanisms. In a multiple regression analysis, serum CRP levels were independently associated with serum cortisol (B= 4.5 x 10-4, p<0.001), urine norepinephrine (B=9.6 x 10-2, p=0.044) and high-frequency power of heart rate variability (B= -3.7 x 10-2, p=0.024).

CONCLUSIONS: In adolescents, CF and CFS 6 months after acute EBV infection are associated with high symptom burden, but no signs of increased viral load and only subtle alterations of immune, autonomic, and neuroendocrine markers of which no one is strongly correlated with symptom scores. A slight sympathetic over parasympathetic predominance is evident in CF and might explain slightly increased CRP levels.

Copyright © 2019. Published by Elsevier Inc.

Source: Kristiansen MS, Stabursvik J, O’Leary EC, Pedersen M, Asprusten TT, Leegaard T, Osnes LT, Tjade T, Skovlund E, Godang K, Wyller VBB. Clinical symptoms and markers of disease mechanisms in adolescent chronic fatigue following Epstein-Barr virus infection: An exploratory cross-sectional study.Brain Behav Immun. 2019 Apr 27. pii: S0889-1591(19)30133-3. doi: 10.1016/j.bbi.2019.04.040. [Epub ahead of print] https://www.ncbi.nlm.nih.gov/pubmed/31039432

Fatigue in Epstein-Barr virus infected adolescents and healthy controls: A prospective multifactorial association study

Abstract:

OBJECTIVE: Acute Epstein-Barr virus (EBV) infection is a known trigger of both acute and chronic fatigue. The aim of this study was to investigate associations to fatigue in adolescents with EBV infection during the initial stage and six months after, as well as in healthy controls.

METHODS: 200 adolescents (12-20 years old) with EBV infection were assessed as soon as possible after the onset of symptoms (EBVbaseline) and six months later (EBVsix months, 5 drop-outs). Also, 70 healthy controls (HC) were included. Associations between current fatigue and 148 different variables (including symptoms, functional abilities and biomarkers) were investigated separately for EBVbaseline, EBVsix months and HC using linear regression modelling.

RESULTS: Fatigue was associated with symptoms of sleeping difficulties, negative emotions, and quality of life under all circumstances. Fatigue was independently associated with markers of immune response at EBVsix months and in HC, not at EBVbaseline. An association between fatigue and markers of autonomic cardiovascular control was only present at EBVsix months. Cognitive functioning shifted from a positive association to fatigue at EBVbaseline to a negative trend at EBVsix months. Markers of infection were not associated with fatigue at EBVbaseline, EBVsix months nor in HC.

CONCLUSION: Irrespective of the cause, fatigue is important for quality of life and is highly associated with negative emotions. Markers of infection and immune response had respectively none and barely any association to fatigue. Autonomic alterations and cognitive dysfunction were exclusively associated with fatigue long after infection, corroborating findings from studies of the Chronic Fatigue Syndrome.

Copyright © 2019. Published by Elsevier Inc.

Source: Pedersen M, Asprusten TT, Godang K, Leegaard TM, Osnes LT, Skovlund E, Tjade T, Øie MG, Wyller VBB. Fatigue in Epstein-Barr virus infected adolescents and healthy controls: A prospective multifactorial association study. J Psychosom Res. 2019 Apr 10. pii: S0022-3999(18)30946-2. doi: 10.1016/j.jpsychores.2019.04.008. [Epub ahead of print] https://www.ncbi.nlm.nih.gov/pubmed/31003854

Epstein-Barr Virus Induced Gene-2 Upregulation Identifies a Particular Subtype of Chronic Fatigue Syndrome/Myalgic Encephalomyelitis

Abstract:

Chronic Fatigue Syndrome/Myalgic Encephalomyelitis (CFS/ME) is a chronic multisystem disease characterized by a variety of symptoms, and exhibits various features of an autoimmune-like disease. Subtypes are well recognized but to date are difficult to identify objectively. The disease may be triggered by infection with a variety of micro-organisms, including Epstein-Barr virus (EBV).

A subset of CFS/ME patients exhibit up regulation of EBV virus induced gene 2 (EBI2) mRNA in peripheral blood mononuclear cells (PBMC), and these patients appear to have a more severe disease phenotype and lower levels of EBNA1 IgG. EBI2 is induced by EBV infection and has been found to be upregulated in a variety of autoimmune diseases. EBI2 is a critical gene in immunity and central nervous system function; it is a negative regulator of the innate immune response in monocytes. Its heterogeneous expression in CFS/ME could explain the variable occurrence of a variety of immune and neurological abnormalities which are encountered in patients with CFS/ME.

The EBI2 subtype occurred in 38-55% CFS/ME patients in our studies. Further work is required to confirm the role of EBV and of EBI2 and its oxysterol ligands in CFS/ME, and to identify the most practical means to identify patients of the EBI subtype. There are two EBI2 antagonists currently in development, and these may hold promise in the treatment of CFS/ME patients of the EBI subtype.

Source: Kerr JR. Epstein-Barr Virus Induced Gene-2 Upregulation Identifies a Particular Subtype of Chronic Fatigue Syndrome/Myalgic Encephalomyelitis. Front Pediatr. 2019 Mar 13;7:59. doi: 10.3389/fped.2019.00059. eCollection 2019. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6424879/ (Full article)

Whole blood human transcriptome and virome analysis of ME/CFS patients experiencing post-exertional malaise following cardiopulmonary exercise testing

Abstract:

Myalgic encephalomyelitis / chronic fatigue syndrome (ME/CFS) is a syndrome of unknown etiology characterized by profound fatigue exacerbated by physical activity, also known as post-exertional malaise (PEM). Previously, we did not detect evidence of immune dysregulation or virus reactivation outside of PEM periods. Here we sought to determine whether cardiopulmonary exercise stress testing of ME/CFS patients could trigger such changes.

ME/CFS patients (n = 14) and matched sedentary controls (n = 11) were subjected to cardiopulmonary exercise on 2 consecutive days and followed up to 7 days post-exercise, and longitudinal whole blood samples analyzed by RNA-seq. Although ME/CFS patients showed significant worsening of symptoms following exercise versus controls, with 8 of 14 ME/CFS patients showing reduced oxygen consumption ([Formula: see text]) on day 2, transcriptome analysis yielded only 6 differentially expressed gene (DEG) candidates when comparing ME/CFS patients to controls across all time points.

None of the DEGs were related to immune signaling, and no DEGs were found in ME/CFS patients before and after exercise. Virome composition (P = 0.746 by chi-square test) and number of viral reads (P = 0.098 by paired t-test) were not significantly associated with PEM. These observations do not support transcriptionally-mediated immune cell dysregulation or viral reactivation in ME/CFS patients during symptomatic PEM episodes.

Source: Bouquet J, Li T, Gardy JL, Kang X, Stevens S, Stevens J, VanNess M, Snell C, Potts J, Miller RR, Morshed M, McCabe M, Parker S, Uyaguari M, Tang P, Steiner T, Chan WS, De Souza AM, Mattman A, Patrick DM, Chiu CY. Whole blood human transcriptome and virome analysis of ME/CFS patients experiencing post-exertional malaise following cardiopulmonary exercise testing. PLoS One. 2019 Mar 21;14(3):e0212193. doi: 10.1371/journal.pone.0212193. eCollection 2019. https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0212193 (Full article)
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A Validated Scale for Assessing the Severity of Acute Infectious Mononucleosis

Abstract:

OBJECTIVES: To develop a scale for the severity of mononucleosis.

STUDY DESIGN: One to 5 percent of college students develop infectious mononucleosis annually, and about 10% meet criteria for chronic fatigue syndrome (CFS) 6 months following infectious mononucleosis. We developed a severity of mononucleosis scale based on a review of the literature. College students were enrolled, generally when they were healthy. When the students developed infectious mononucleosis, an assessment was made as to the severity of their infectious mononucleosis independently by 2 physicians using the severity of mononucleosis scale. This scale was correlated with corticosteroid use and hospitalization. Six months following infectious mononucleosis, an assessment is made for recovery from infectious mononucleosis or meeting 1 or more case definitions of CFS.

RESULTS: In total, 126 severity of mononucleosis scales were analyzed. The concordance between the 2 physician reviewers was 95%. All 3 hospitalized subjects had severity of mononucleosis scores ≥2. Subjects with severity of mononucleosis scores of ≥1 were 1.83 times as likely to be given corticosteroids. Students with severity of mononucleosis scores of 0 or 1 were less likely to meet more than 1 case definition of CFS 6 months following infectious mononucleosis.

CONCLUSIONS: The severity of mononucleosis scale has interobserver, concurrent and predictive validity for hospitalization, corticosteroid use, and meeting criteria for CFS 6 months following infectious mononucleosis.

Copyright © 2019 Elsevier Inc. All rights reserved.

Source: Katz BZ, Reuter C, Lupovitch Y, Gleason K, McClellan D, Cotler J, Jason LA. A Validated Scale for Assessing the Severity of Acute Infectious Mononucleosis. J Pediatr. 2019 Mar 7. pii: S0022-3476(19)30123-4. doi: 10.1016/j.jpeds.2019.01.035. [Epub ahead of print] https://www.ncbi.nlm.nih.gov/pubmed/30853204

Chronic viral infections in myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS)

Abstract:

BACKGROUND AND MAIN TEXT: Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) is a complex and controversial clinical condition without having established causative factors. Increasing numbers of cases during past decade have created awareness among patients as well as healthcare professionals. Chronic viral infection as a cause of ME/CFS has long been debated. However, lack of large studies involving well-designed patient groups and validated experimental set ups have hindered our knowledge about this disease. Moreover, recent developments regarding molecular mechanism of pathogenesis of various infectious agents cast doubts over validity of several of the past studies.

CONCLUSIONS: This review aims to compile all the studies done so far to investigate various viral agents that could be associated with ME/CFS. Furthermore, we suggest strategies to better design future studies on the role of viral infections in ME/CFS.

Source: Rasa S, Nora-Krukle Z, Henning N, Eliassen E, Shikova E, Harrer T, Scheibenbogen C, Murovska M, Prusty BK6; European Network on ME/CFS (EUROMENE). Chronic viral infections in myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS). J Transl Med. 2018 Oct 1;16(1):268. doi: 10.1186/s12967-018-1644-y. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6167797/ (Full article)