Can abstract class be a parameter in a controller's action?

Question

I have an Action function inside of a Controller, which is being called with AJAX. That Action is taking in 1 parameter. Client side, I construct a JSON object which shoul

Answer 1

If you have access to the controller could you add another class that inherits the abstract class without specifing any member, and use that to serialize deserialize, and then return its base onto the other layer?

I know this is not good practice but some hack however I don't know if abstract classes can be serialized in some way.