EBV causes MS in genetically susceptible individuals by infecting a white blood cell, these infected cell seed the nervous system where they produce pathogenic autoantibodies and promote the survival of autoimmue T cells that would normally be eliminated. Thus, the virus promotes the autoimmune process.
Studies on EBV in lupus patients show increased EBV viral load, abnormal expression a decreased immune response to EBV, and increased levels of EBV-directed antibodies. As EBV is known to be controlled by cell-mediated immunity, the reduced EBV-specific T-cell response in SLE patients may result in defective control of EBV causing frequent reactivation. These high antibody levels have been shown to react with normal cells thus promoting a cross reactive autoimmunity, causing lupus.