AHMF: 98 Conference: DeMeirLeir

Low Molecular Weight RNaseL in CFS

K. De Meirleir [1], I. Campine [1], P. De Becker [1], E. Van Steenberge [1], C. Bisbal [2], T.Salezadah [2], B. Lebleu [2]

1 Human Physiology and Medicine
V.U.B.
Brussels
Belgium
2 Institut de Genetique Moleculaire de Montpellier
CNRS
Montpellier
France

Chronic fatigue syndrome (CFS) is associated with persistent and debilitating fatigue, with cognitive dysfunction and with other symptoms. Its unknown aetiology and the absence of biochemical markers complicate diagnostic. Activation of immune responses and infection by several viruses have been suggested in several studies. Recent studies by Suhadolnik et al. have pointed to increased levels of 2-5A and RNaseL activity in PBMC from CFS patients, as well as to previously unrecognised low molecular weight forms of RNase L in a small group of severely disabled CFS patients.

In keeping with these observations we are providing evidence for the presence of a 37 kDa 2-5A binding polypeptide in PBMC extracts from a large cohort of CFS patients. The relation if any between this 37 kDa polypeptide, the increased RNase L activity and the physiopathology of CFS cannot be ascertained at the present time. Likewise the molecular mechanisms underlying the accumulation of this 37 kDa polypeptide are unknown although proteolytic degradation in the extracts can be eliminated.

These observations could provide the basis for the development of a biochemical assay for the differential diagnostic of CFS and for the follow up of its clinical evolution.

Supported by grants from ARC and CFIDS Association of America to BL. I Campine is "Aspirant"of the Fund of Scientific Research (Belgium).