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Virology

Enteroviruses 

One of the poster presentations made by Dr. John Chia and his son, Andrew Chia, demonstrated that enteroviral infections were frequently found in CFS. Their research confirmed enteroviruses (EV) in the tissue samples taken from 132 consecutive stomach biopsies of CFS patients. (Some of these patients also had gastrointestinal symptoms). The majority of CFS cases tested positive— 82% had viral protein and 64% had viral nucleic acid, while EV was found in only a small fraction of controls (i.e., 10% or 4 of 40 controls).

In addition, when biopsied material that looked like it contained viral antigens and proteins was injected into animals which were later checked for replicating virus, many of them revealed production of antiviral proteins and antibodies to the EV. The importance of this study, according to Dr. Komaroff, was that the Chias’ research suggests EV may play a central role in this illness.

XMRV and pMLV false-positive results came from contamination

Topics of utmost interest at the Ottawa conference were xenotropic murine leukemia retroviruses (XMRV) and polytropic murine leukemia viruses (pMLVs), especially since the results of the multi-laboratory XMRV/MLV study were being published by Science at the same time. Dr. Komaroff briefly touched on the differences in research findings, from the original data published by Whittemore Peterson Institute (WPI) to the final results of the Blood Working Group Study.

Two years ago, WPI came out with some remarkable information: a significant percentage of CFS patients were found to have viral nucleic acid and viral antigen to XMRV; that the virus could be cultivated from patients’ plasma and cells; that antibodies to the virus were found in CFS patients; and moreover, that some of the healthy blood donors had also tested positive.

A second study by scientists from the National Institutes of Health (NIH) and Food and Drug Administration (FDA) only looked for XMRV viral nucleic acid, which they failed to confirm. However, they detected MLV-related virus in CFS. Many laboratories around the world tried to repeat the studies, but results came back negative and/or with inconsistencies. A large replication study was established to verify these findings. The research was spread across 9 highly reputable laboratories that conducted blinded testing of blood samples from a large CFS patient group, including those which had previously tested positive for XMRV or pMLVs. But the results were negative.

False positives of XMRV /pMLVs are now attributed to contamination of laboratory reagents and commercial reagents with mouse DNA. Dr. Komaroff indicated that XMRV was an accidental laboratory recombinant virus, going back to the early 1990s and considered this finding in itself as troubling, because quite a few people developed CFS many years prior to this incident.

Various cell lines were also found to be contaminated with mouse DNA and this contamination is considered to be widespread, affecting many laboratories around the world. In view of these results and developments, Dr. Komaroff regards XMRV/ pMLVS research to be on very “shaky grounds.”