J Clin Microbiol 2002 Nov;40(11):4131-4137
Caselli E, Boni M, Bracci A, Rotola A, Cermelli C, Castellazzi M, Di Luca D, Cassai E.
Section of Microbiology, Department of Experimental and Diagnostic Medicine. Section of Neurology, Department of Medical Surgical, Communication and Behavioral Sciences, University of Ferrara, Ferrara. Department of Hygienistic, Microbiological and Biostatistical Sciences, University of Modena and Reggio Emilia, Modena, Italy.
The association between human herpesvirus 6 (HHV-6) and multiple sclerosis (MS) is controversial.
In fact, it is difficult to establish a causative role of HHV-6, due to the high prevalence of latently infected individuals in the healthy population.
Therefore, the presence of virus sequences in tissue biopsy does not support a viral role, and serological assays do not show significant differences between MS patients and control populations.
The only viral gene expressed during latency is U94/rep.
Therefore, we have developed a serological assay for the detection of antibodies specifically directed against U94/REP protein.
Different populations were analyzed by enzyme-linked immunosorbent assay, including healthy controls, MS patients, and subjects with diseases unrelated to HHV-6 infection, including other neurological diseases.
The results show statistically significant differences (P > 0.01) between MS patients and control groups, both in antibody prevalence (87 and 43.9%, respectively) and in geometric mean titer (1:515 and 1:190, respectively).
The detection of antibodies specific for HHV-6 U94/REP shows that the immune system is exposed to this antigen during natural infection.
The higher prevalence and higher titers of antibodies to U94/REP suggest that MS patients and control groups might experience different exposures to HHV-6.