Immunopathology associated with Epstein-Barr virus (EBV) infection: Evidence for interactions with T-lymphocyte EBV receptor CD21

Epstein-Barr virus (EBV), also termed Human Herpes Virus 4, is the causative agent of infectious mononucleosis and may be a cofactor in some human cancers. The virus has also been suggested to play a role in human autoimmune diseases including rheumatoid arthritis, systemic lupus erythematosus, and multiple sclerosis. X-linked lymphoproliferative syndrome caused by the deficiency of the Sarc homology 2 domain protein 1A, also termed signaling lymphocyte activation marker-associated protein, can result in immune dysfunction and death after EBV infection. The EBV-related immunopathology in X-linked lymphoproliferative syndrome and prototypical autoimmune syndromes is summarized in this review. A novel model of viral interaction with complement receptor CD21, which is also the receptor for EBV, is proposed to account for both the immunological abnormalities of X-linked lymphoproliferative syndrome and autoimmune diseases associated with EBV infection. The pathogenesis of both X-linked lymphoproliferative syndrome and EBV-associated immune diseases is proposed to result from increased direct infection of T cells by EBV through the T-cell complement receptor CD21 expressed on T cells. A prediction of this model is that therapy designed to decrease CD21-mediated EBV infection of T lymphocytes could also be beneficial in the treatment of some autoimmune diseases.