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See no evil, hear no evil, do no evil: the lessons of immune privilege

Abstract

Immune-mediated inflammation and allograft rejection are greatly reduced in certain organs, a phenomenon called 'immune privilege'. Immune privilege is well developed in three regions of the body: the eye, the brain and the pregnant uterus. Immune-mediated inflammation has devastating consequences in the eye and brain, which have limited capacity for regeneration. Likewise, loss of immune privilege at the maternal-fetal interface culminates in abortion in rodents. However, all three regions share many adaptations that restrict the induction and expression of immune-mediated inflammation. A growing body of evidence from rodent studies suggests that a breakdown in immune privilege contributes to multiple sclerosis, uveitis, corneal allograft rejection and possibly even immune abortion.

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Acknowledgements

I dedicate this review to the memory of J.W. Streilein, who contributed substantially to the understanding of immune-privileged sites. Supported by Research to Prevent Blindness.

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The author declares no competing financial interests.

Correspondence to Jerry Y Niederkorn.

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Figure 1: Organ systems involved in the induction of ACAID.