How Shylock as an antagonist ?

On the surface of things, Shylock could be seen as an antagonist. He is a Jewish moneylender in Venice. He demands a pound of flesh from Antonio, but is forced to convert to Christianity by the end of the play. He loses his daughter Jessica and most of his wealth. Shakespeare does an interesting thing by letting the audience sympathize with Shylock near the end of the play. This puts into question how much of an antagonist Shylock really is.