A different response to cytomegalovirus (CMV) and Epstein–Barr virus (EBV) infection in UK people with multiple sclerosis (PwMS) compared to controls

Abstract

The nature of past cytomegalovirus (CMV) infection in multiple sclerosis (MS) populations is relatively unexplored. Relationships between CMV infection markers and Epstein-Barr virus (EBV) infection markers in a UK resident population of people with MS (PwMS) and controls have been investigated. CMV and EBV nuclear antigen-1(EBNA-1)/virus capsid antigen (VCA) IgG levels were determined for 78 MS patients and anonymised controls by enzyme immunoassays. CMV IgG levels were expressed as Paul Ehrlich Institute (PEI) units/ml (U/ml) and EBNA-1/VCA IgG levels as enzyme units/ml. CMV IgG seroprevalence was lower (p = 0.0003) in PwMS (35.9% [95%CI: 25.2-46.5]) compared to controls (62.9% [95%CI:54.4-71.4). CMV IgG geometric mean levels in PwMS (353 PEI U/ml [95%CI:272-457]) were lower (p = 0.03) compared to the controls (492 PEI U/ml [95%CI:405-599]). EBNA-1 IgG levels were higher (p<0.0001) in PwMS compared to the controls and were lower (p = 0.238) in CMV seropositive PwMS (49.4 units/ml [95%CI:32.2-75.6]) compared to CMV seronegative PwMS (65.4 units/ml [95%CI:53.4-80.1]). These effects were not apparent with EBV VCA IgG. Several aspects of CMV and EBV infection in PwMS appear to differ compared to controls. The potential immunomodulatory effect of CMV infection on MS disease and potential interactions with EBV require further investigation.