A multicenter blinded analysis indicates no association between chronic fatigue syndrome/myalgic encephalomyelitis and either xenotropic murine leukemia virus-related virus or polytropic murine leukemia virus

Abstract:

The disabling disorder known as chronic fatigue syndrome or myalgic encephalomyelitis (CFS/ME) has been linked in two independent studies to infection with xenotropic murine leukemia virus-related virus (XMRV) and polytropic murine leukemia virus (pMLV). Although the associations were not confirmed in subsequent studies by other investigators, patients continue to question the consensus of the scientific community in rejecting the validity of the association. Here we report blinded analysis of peripheral blood from a rigorously characterized, geographically diverse population of 147 patients with CFS/ME and 146 healthy subjects by the investigators describing the original association. This analysis reveals no evidence of either XMRV or pMLV infection. I

MPORTANCE Chronic fatigue syndrome/myalgic encephalomyelitis has an estimated prevalence of 42/10,000 in the United States, with annual direct medical costs of $7 billion. Here, the original investigators who found XMRV and pMLV (polytropic murine leukemia virus) in blood of subjects with this disorder report that this association is not confirmed in a blinded analysis of samples from rigorously characterized subjects. The increasing frequency with which molecular methods are used for pathogen discovery poses new challenges to public health and support of science. It is imperative that strategies be developed to rapidly and coherently address discoveries so that they can be carried forward for translation to clinical medicine or abandoned to focus resource investment more productively. Our study provides a paradigm for pathogen discovery that may be helpful to others working in this field.

 

Source: Alter HJ, Mikovits JA, Switzer WM, Ruscetti FW, Lo SC, Klimas N, Komaroff AL, Montoya JG, Bateman L, Levine S, Peterson D, Levin B, Hanson MR, Genfi A, Bhat M, Zheng H, Wang R, Li B, Hung GC, Lee LL, Sameroff S, Heneine W, Coffin J, Hornig M, Lipkin WI. A multicenter blinded analysis indicates no association between chronic fatigue syndrome/myalgic encephalomyelitis and either xenotropic murine leukemia virus-related virus or polytropic murine leukemia virus. MBio. 2012 Sep 18;3(5). pii: e00266-12. doi: 10.1128/mBio.00266-12. Print 2012. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3448165/ (Full article)

 

Failure to confirm XMRV/MLVs in the blood of patients with chronic fatigue syndrome: a multi-laboratory study

Abstract:

Murine leukemia viruses (MLVs), including xenotropic-MLV-related virus (XMRV), have been controversially linked to chronic fatigue syndrome (CFS). To explore this issue in greater depth, we compiled coded replicate samples of blood from 15 subjects previously reported to be XMRV/MLV-positive (14 with CFS) and from 15 healthy donors previously determined to be negative for the viruses. These samples were distributed in a blinded fashion to nine laboratories, which performed assays designed to detect XMRV/MLV nucleic acid, virus replication, and antibody. Only two laboratories reported evidence of XMRV/MLVs; however, replicate sample results showed disagreement, and reactivity was similar among CFS subjects and negative controls. These results indicate that current assays do not reproducibly detect XMRV/MLV in blood samples and that blood donor screening is not warranted.

 

Source: Simmons G, Glynn SA, Komaroff AL, Mikovits JA, Tobler LH, Hackett J Jr, Tang N, Switzer WM, Heneine W, Hewlett IK, Zhao J, Lo SC, Alter HJ, Linnen JM, Gao K, Coffin JM, Kearney MF, Ruscetti FW, Pfost MA, Bethel J, Kleinman S, Holmberg JA, Busch MP; Blood XMRV Scientific Research Working Group (SRWG). Failure to confirm XMRV/MLVs in the blood of patients with chronic fatigue syndrome: a multi-laboratory study. Science. 2011 Nov 11;334(6057):814-7. doi: 10.1126/science.1213841. Epub 2011 Sep 22. Collaborators (25) https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3299483/ (Full article)

 

Myalgic encephalomyelitis: International Consensus Criteria

Abstract:

The label ‘chronic fatigue syndrome’ (CFS) has persisted for many years because of the lack of knowledge of the aetiological agents and the disease process. In view of more recent research and clinical experience that strongly point to widespread inflammation and multisystemic neuropathology, it is more appropriate and correct to use the term ‘myalgic encephalomyelitis’ (ME) because it indicates an underlying pathophysiology. It is also consistent with the neurological classification of ME in the World Health Organization’s International Classification of Diseases (ICD G93.3).

Consequently, an International Consensus Panel consisting of clinicians, researchers, teaching faculty and an independent patient advocate was formed with the purpose of developing criteria based on current knowledge. Thirteen countries and a wide range of specialties were represented. Collectively, members have approximately 400 years of both clinical and teaching experience, authored hundreds of peer-reviewed publications, diagnosed or treated approximately 50 000 patients with ME, and several members coauthored previous criteria. The expertise and experience of the panel members as well as PubMed and other medical sources were utilized in a progression of suggestions/drafts/reviews/revisions.

The authors, free of any sponsoring organization, achieved 100% consensus through a Delphi-type process. The scope of this paper is limited to criteria of ME and their application. Accordingly, the criteria reflect the complex symptomatology. Operational notes enhance clarity and specificity by providing guidance in the expression and interpretation of symptoms. Clinical and research application guidelines promote optimal recognition of ME by primary physicians and other healthcare providers, improve the consistency of diagnoses in adult and paediatric patients internationally and facilitate clearer identification of patients for research studies.

© 2011 The Association for the Publication of the Journal of Internal Medicine.

Comment in: A controversial consensus–comment on article by Broderick et al. [J Intern Med. 2012]

 

Source: Carruthers BM, van de Sande MI, De Meirleir KL, Klimas NG, Broderick G, Mitchell T, Staines D, Powles AC, Speight N, Vallings R, Bateman L, Baumgarten-Austrheim B, Bell DS, Carlo-Stella N, Chia J, Darragh A, Jo D, Lewis D, Light AR, Marshall-Gradisbik S, Mena I, Mikovits JA, Miwa K, Murovska M, Pall ML, Stevens S. Myalgic encephalomyelitis: International Consensus Criteria. J Intern Med. 2011 Oct;270(4):327-38. doi: 10.1111/j.1365-2796.2011.02428.x. Epub 2011 Aug 22. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3427890/ (Full article)

 

Xenotropic murine leukemia virus-related virus-associated chronic fatigue syndrome reveals a distinct inflammatory signature

Abstract:

BACKGROUND: The recent identification of xenotropic murine leukemia virus-related virus (XMRV) in the blood of patients with chronic fatigue syndrome (CFS) establishes that a retrovirus may play a role in the pathology in this disease. Knowledge of the immune response might lead to a better understanding of the role XMRV plays in this syndrome. Our objective was to investigate the cytokine and chemokine response in XMRV-associated CFS.

MATERIALS AND METHODS: Using Luminex multi-analyte profiling technology, we measured cytokine and chemokine values in the plasma of XMRV-infected CFS patients and compared these data to those of healthy controls. Analysis was performed using the Gene Expression Pattern Analysis Suite and the Random Forest tree classification algorithm.

RESULTS: This study identifies a signature of 10 cytokines and chemokines which correctly identifies XMRV/CFS patients with 93% specificity and 96% sensitivity.

CONCLUSION: These data show, for the first time, an immunological pattern associated with XMRV/CFS.

 

Source: Lombardi VC, Hagen KS, Hunter KW, Diamond JW, Smith-Gagen J, Yang W, Mikovits JA. Xenotropic murine leukemia virus-related virus-associated chronic fatigue syndrome reveals a distinct inflammatory signature. In Vivo. 2011 May-Jun;25(3):307-14. https://www.ncbi.nlm.nih.gov/pubmed/21576403

 

Detection of an infectious retrovirus, XMRV, in blood cells of patients with chronic fatigue syndrome

Abstract:

In October 2009, we reported the first direct isolation of infectious xenotropic murine leukemia virus-related virus (XMRV). In that study, we used a combination of biological amplification and molecular enhancement techniques to detect XMRV in more than 75% of 101 patients with chronic fatigue syndrome (CFS). Since our report, controversy arose after the publication of several studies that failed to detect XMRV infection in their CFS patient populations. In this addenda, we further detail the multiple detection methods we used in order to observe XMRV infection in our CFS cohort. Our results indicate that PCR from DNA of unstimulated peripheral blood mononuclear cells is the least sensitive method for detection of XMRV in subjects’ blood. We advocate the use of more than one type of assay in order to determine the frequency of XMRV infection in patient cohorts in future studies of the relevance of XMRV to human disease.

 

Source: Mikovits JA, Lombardi VC, Pfost MA, Hagen KS, Ruscetti FW. Detection of an infectious retrovirus, XMRV, in blood cells of patients with chronic fatigue syndrome. Virulence. 2010 Sep-Oct;1(5):386-90. doi: 10.4161/viru.1.5.12486. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3073172/ (Full article)

 

Distribution of xenotropic murine leukemia virus-related virus (XMRV) infection in chronic fatigue syndrome and prostate cancer

Abstract:

In 2006, sequences described as xenotropic murine leukemia virus-related virus (XMRV) were discovered in prostate cancer patients. In October 2009, we published the first direct isolation of infectious XMRV from humans and the detection of infectious XMRV in patients with chronic fatigue syndrome. In that study, a combination of classic retroviral methods were used including: DNA polymerase chain reaction and reverse transcriptase polymerase chain reaction for gag and env, full length genomic sequencing, immunoblotting for viral protein expression in activated peripheral blood mononuclear cells, passage of infectious virus in both plasma and peripheral blood mononuclear cells to indicator cell lines, and detection of antibodies to XMRV in plasma. A combination of these methods has since allowed us to confirm infection by XMRV in 85% of the 101 patients that were originally studied.

Since 2009, seven studies, predominantly using DNA polymerase chain reaction of blood products or tumor tissue, have reported failures to detect XMRV infection in patients with either prostate cancer or chronic fatigue syndrome. A review of the current literature on XMRV supports the importance of applying multiple independent techniques in order to determine the presence of this virus. Detection methods based upon the biological and molecular amplification of XMRV, which is usually present at low levels in unstimulated blood cells and plasma, are more sensitive than assays for the virus by DNA polymerase chain reaction of unstimulated peripheral blood mononuclear cells.

When we examined patient blood samples that had originally tested negative by DNA polymerase chain reaction by more sensitive methods, we observed that they were infected with XMRV; thus, the DNA polymerase chain reaction tests provided false negative results.

Therefore, we conclude that molecular analyses using DNA from unstimulated peripheral blood mononuclear cells or from whole blood are not yet sufficient as stand-alone assays for the identification of XMRV-infected individuals. Complementary methods are reviewed, that if rigorously followed, will likely show a more accurate snapshot of the actual distribution of XMRV infection in humans.

 

Source: Mikovits JA, Huang Y, Pfost MA, Lombardi VC, Bertolette DC, Hagen KS, Ruscetti FW. Distribution of xenotropic murine leukemia virus-related virus (XMRV) infection in chronic fatigue syndrome and prostate cancer. AIDS Rev. 2010 Jul-Sep;12(3):149-52. https://www.ncbi.nlm.nih.gov/pubmed/20842203

 

Detection of an infectious retrovirus, XMRV, in blood cells of patients with chronic fatigue syndrome

Abstract:

Chronic fatigue syndrome (CFS) is a debilitating disease of unknown etiology that is estimated to affect 17 million people worldwide. Studying peripheral blood mononuclear cells (PBMCs) from CFS patients, we identified DNA from a human gammaretrovirus, xenotropic murine leukemia virus-related virus (XMRV), in 68 of 101 patients (67%) as compared to 8 of 218 (3.7%) healthy controls. Cell culture experiments revealed that patient-derived XMRV is infectious and that both cell-associated and cell-free transmission of the virus are possible. Secondary viral infections were established in uninfected primary lymphocytes and indicator cell lines after their exposure to activated PBMCs, B cells, T cells, or plasma derived from CFS patients. These findings raise the possibility that XMRV may be a contributing factor in the pathogenesis of CFS.

Comment in:

Erratum in: Partial retraction. Detection of an infectious retrovirus, XMRV, in blood cells of patients with chronic fatigue syndrome. [Science. 2011]

Retraction in: Retraction. [Science. 2011]

 

Source: Lombardi VC, Ruscetti FW, Das Gupta J, Pfost MA, Hagen KS, Peterson DL, Ruscetti SK, Bagni RK, Petrow-Sadowski C, Gold B, Dean M, Silverman RH, Mikovits JA. Detection of an infectious retrovirus, XMRV, in blood cells of patients with chronic fatigue syndrome. Science. 2009 Oct 23;326(5952):585-9. doi: 10.1126/science.1179052. Epub 2009 Oct 8. http://science.sciencemag.org/content/326/5952/585.long (Full article)