Immunopathology & Immunotherapy

Autoimmune Dis. 2012; 2012: 189096.

Published online 2012 January 24. doi:  10.1155/2012/189096PMCID: PMC3270541CD8+ T-Cell Deficiency, Epstein-Barr Virus Infection, Vitamin D Deficiency, and Steps to Autoimmunity: A Unifying HypothesisMichael P. Pender Conclusions

CD8+ T-cell deficiency is a general feature of chronic autoimmune diseases and also occurs in healthy blood relatives of patients with these diseases. It is proposed that this deficiency is genetically determined and underlies the development of chronic autoimmune diseases by impairing CD8+ T-cell control of EBV infection, with the result that EBV-infected autoreactive B cells accumulate in the target organ where they produce pathogenic autoantibodies and provide costimulatory survival signals to autoreactive T cells. Autoimmunity is postulated to evolve in a series of steps culminating in the development of ectopic lymphoid follicles containing EBV-infected autoreactive B cells in the target organ. It is also proposed that deprivation of sunlight and vitamin D facilitates the development of autoimmune diseases by aggravating the CD8+ T cell deficiency and thereby further impairing control of EBV. The hypothesis makes predictions which can be tested, including the prevention and successful treatment of chronic autoimmune diseases by controlling EBV infection.