Beta-interferon treatment reduces human herpesvirus-6 viral load in multiple sclerosis relapses but not in remission.
To determine whether the DNA prevalence of human herpesvirus-6 (HHV-6), the viral load and the prevalence of both HHV-6 variants in relapsing-remitting multiple sclerosis (RRMS) patients in exacerbation are altered by beta-interferon (IFN-beta) treatment, in comparison with RRMS patients in remission, we analyzed HHV-6 (A and B) genomes in 189 serum samples by quantitative real-time polymerase chain reaction: 105 of the RRMS patients were receiving IFN-beta treatment (48 in exacerbation) and 84 were untreated (36 in relapse). The results were as follows. (1) Prevalence decrease because of IFN-beta treatment was not significant: 25% of RRMS patients in relapse vs. 15.9% in remission (p = 0.45). (2) Viral load was twice as much in untreated patients in relapse than in treated ones. (3) We only found variant A. Since IFN-beta treatment is able to significantly reduce HHV-6 viral load in RRMS patients in relapse, but not in remission, we suggest a role for HHV-6 in the pathogenesis of multiple sclerosis exacerbations and an antiviral role for IFN-beta treatment in RRMS.
Alvarez-Lafuente
Roberto
R
Unidad de Investigación, Hospital Clínico San Carlos, Madrid, España. labesmul@hcsc.es
De Las Heras
Virginia
V
Bartolomé
Manuel
M
Picazo
Juan José
JJ
Arroyo
Rafael
R
D000328:Adult; D000998:Antiviral Agents / Q000627:therapeutic use*; D015331:Cohort Studies; D004279:DNA, Viral / Q000097:blood / Q000187:drug effects* / Q000235:genetics; D005260:Female; D015654:Herpesvirus 6, Human / Q000187:drug effects* / Q000502:physiology; D006801:Humans; D016899:Interferon-beta / Q000627:therapeutic use*; D008297:Male; D008875:Middle Aged; D020528:Multiple Sclerosis, Chronic Progressive / Q000097:blood / Q000188:drug therapy / Q000821:virology*; D012016:Reference Values; D020133:Reverse Transcriptase Polymerase Chain Reaction / Q000379:methods; D019562:Viral Load / Q000379:methods
D000998:Antiviral Agents; D004279:DNA, Viral; D016899:Interferon-beta