Immune Privilege: Do Your Eyes Have a 'Separate' Immune System?

To protect your vision, the human eye gets something called immune privilege. It is basically a license that the bodys immune system gives to some organs, like the eyes and the brain. Immune privilege limits the response of the immune system in those immune-privileged organs. Think of immune privilege as immunity from the bodys immunity.

However, like everything, theres a downside to this immune privilege of the eye. The immune privilege is easily circumvented when an excessively strong immune response is encountered. This may leave the privileged tissue at risk of collateral damage, as its natural defenses are more easily broken. The immune system promptly deals with foreign antigens in normal tissue and restores normalcy. But that isnt always straightforward when it comes to our eyes.