DETECTION OF HERPESVIRIDAE IN POSTMORTEM MULTIPLE-SCLEROSIS BRAIN-TISSUE AND CONTROLS BY POLYMERASE CHAIN-REACTION

Objective: To test for the presence of herpesviruses in postmortem bra in samples from multiple sclerosis patients and controls using polymer ase chain reaction. Background: Herpes simplex virus, varicella-zoster virus, Epstein-Barr virus, cytomegalovirus, and human herpesvirus-6 a re common viruses capable of persistence and latency. All have been de tected in the CNS. Methods: Active and inactive plaque tissue, unaffec ted white matter (WM) and gray matter (GM) from MS cases, and WM and G M controls (Alzheimer's disease, Parkinson's disease and non-neurologi cal disease) were screened for the herpesvirus by PCR. Results: (1) 37 % of the MS cases were positive for herpes simplex virus (HSV). Twenty -eight percent of controls cases were positive for HSV. Forty-one perc ent of active plaques were positive for HSV in contrast to only 20% of inactive plaques (Sanders ef al, 1996). (2) 57% of the MS cases and 4 3% of the control cases were positive for HHV-6. Thirty-two percent of the active plaques contained HHV-6 compared to 17% of inactive plaque s. (3) 43% of the MS cases and 32% of the control cases were positive for VZV. Fourteen percent of the active plaques and 10% ofthe inactive plaques were positive for VZV. (4) 27% of MS cases and 38% of control cases were positive for EBV. Five percent of the active plaques were positive for EBV and 10% ofthe inactive plaques were positive. (5) 16% of the MS cases and 22% ofthe controls were positive for CMV. Nine pe rcent ofthe active plaques and 10% ofthe inactive plaques were positiv e. We also compared MS WM and GM with controls and found no significan t difference. Conclusions: HSV, HHV-6, and VZV were present in a great er frequency of MS cases compared to controls; however, no statistical differences were noted. The presence of herpesvirus in all tissue mak es an etiologic association to MS uncertain. Cellular localization of virus and its relationship to pathology and latency may reveal an asso ciation.