How can I access the Apple SDK for Accessibility from Unity?

I'm trying to develop a game, and I am concerned with the Accessibility feature. I would like blind end user to interact with my application using VoiceOver, and/or their own screen reader. For that, Apple provides a bunch of control implementing the NSAccessibility protocol. Since I will provide a buncg of custom control in my game, I would like those game objects to implement the NSAccessibility protocol as well.

How can I achieve that from the C# code in Unity?