Multiple sclerosis-associated retrovirus in early multiple sclerosis: a six-year follow-up of a Sardinian cohort.
The human endogenous retroviruses (HERV)-W family contains an extracellular particle detected in multiple sclerosis (MS) patients and designated as MS-associated retrovirus (MSRV). Through nested RT-PCR assays specific for pol MSRV gene, we preliminary reported that its presence in the cerebrospinal fluid (CSF) of early MS patients could be indicative of a poor prognosis upon a three-year follow-up. In the present clinical study, we enlarged our blind observation up to six years. At study entry, 10 MS patients were MSRV+ and eight were MSRV- in the CSF, both groups having a similar mean age and Expanded Disability Status Scale (EDSS) score. After six year follow-up, the mean EDSS significantly differed between the MSRV+ and MSRV- cohorts (4.3 versus 2.2; P = 0.004), as did the annual relapse rate (0.5 in the MSRV+ versus 0.3 in the MSRV-; P = 0.01). Finally, two MSRV+ patients entered the progressive phase, whilst none of the MSRV- group entered this phase, and 9/10 MSRV+ versus 2/8 MSRV patients were treated with immunomodulatory or immunosuppressive drugs (P = 0.009). In conclusion, we found that the presence of MSRV virions in the CSF at the onset of MS is associated, not only with disability accumulation, but also with a higher rate of clinical re-exacerbations. With the known potential pathogenic effects of MSRV given in the literature, further investigations on MSRV are warranted.
Sotgiu
S
S
Institute of Clinical Neurology, University of Sassari, Viale San Pietro 10, 07100, Sassari, Italy. stesot@hotmail.com
Arru
G
G
Mameli
G
G
Serra
C
C
Pugliatti
M
M
Rosati
G
G
Dolei
A
A
D000293:Adolescent; D000328:Adult; D002555:Cerebrospinal Fluid / Q000821:virology; D015331:Cohort Studies; D004185:Disability Evaluation; D020077:Endogenous Retroviruses / Q000235:genetics / Q000302:isolation & purification* / Q000378:metabolism; D005260:Female; D005500:Follow-Up Studies; D015751:Genes, pol; D006801:Humans; D007558:Italy / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D020529:Multiple Sclerosis, Relapsing-Remitting / Q000453:epidemiology* / Q000821:virology*; D016133:Polymerase Chain Reaction; D011237:Predictive Value of Tests; D011379:Prognosis