Ancient Retrovirus May Contribute to Chronic Fatigue Syndrome

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Market Wire > June, 2008

Ancient Retrovirus May Contribute to Chronic Fatigue Syndrome, Multiple

Sclerosis and

Autoimmunity

Brigitte Huber, PhD, of the Tufts University School of Medicine, presented

evidence at a

medical conference that suggested that a reactivated ancient retrovirus embedded

in the

human genome may be active in chronic fatigue syndrome (CFS) and multiple

sclerosis

(MS) patients. Danish scientists at the same conference suggested that the

activation of

this retrovirus, dormant in healthy individuals, could be the reason why

autoimmune

conditions worsen with viral infections.

Chronic Fatigue Syndrome and Multiple Sclerosis Patients at Increased Risk From

the

Effects of HERV-K18 Activation

" Patients with profoundly fatiguing diseases such as MS and CFS may be

particularly

susceptible to HERV-K18 activation, " said Dr. Huber. The announcement was made

at the

International Symposium on Viruses in CFS and Post-Viral Fatigue, a satellite

conference

of the 6th International Conference on HHV-6 & 7. Using an SNP-based genotyping

method, Dr. Huber found that both MS and CFS patients (whose illness had been

triggered

by infectious mononucleosis) were at a higher relative risk for containing

HERV-K18

variants known to induce superantigen activity. Superantigens are proteins that

are able to

induce a strong undifferentiated T-cell response believed to deplete the immune

system

over time.

Viral activity and/or immune activation has been shown to trigger HERV-K18

activity. Both

Epstein-Barr virus infection (infectious mononucleosis) and interferon-alpha

administration are associated with HERV-K18 activity. " HHV-6 activates HERV-K18

as

well, " said Danish investigator Per Hollsberg, MD and professor from the

University of

Aarhus In Denmark. His PhD student Vanda Lauridsen Turcanova presented this data

at

the same conference. " Furthermore, this retrovirus activation may have important

consequences for autoimmunity, " he added.

HERV-K18 activation may be the endpoint of an HHV6/EBV interferon pathway

operating

in both MS and CFS. HHV-6 is being investigated as a co-factor in both diseases.

Other

retroviruses, HERV-H and HERV-W, have been implicated in MS by other

researchers. Over

75% of MS patients meet the criteria for CFS. Fatigue is often the most

disabling symptom

for MS patients. The two diseases also share characteristics such as grey matter

atrophy,

impaired cerebral glucose metabolism, autonomic nervous system activity and

altered

patterns of brain activity.

Dr. Huber's study suggests that endogenous retroviral activation in CFS and MS

could

produce some of the symptoms associated with both diseases. She has received a

National

Institutes of Health (NIH) grant to study these issues. Per Hollsberg has done

extensive

research on the role of EBV and HHV-6 in multiple sclerosis.

The HHV-6 Foundation

The HHV-6 Foundation encourages scientific exchanges and provides grants to

researchers seeking to increase our understanding of HHV-6 infection in a wide

array of

central nervous system disorders. Daram Ablashi, the co-discoverer of the HHV-6

virus, is

the Foundation's Scientific Director.