A deed is a written document that transfers rights from one party to another.
Your parents are the only people who can take their names off the title, and they would do that by deeding - in writing - their interest in the property to you and / or your wife.
Transferring interests in real property can have serious consequences, and must not be done without consulting with an attorney and an accountant to determine whether you are following the proper course of action. Mistakes when transferring title can have enormous - by which I mean, "expensive" - consequences.
I recommend you do some home work in order to avoid some legal issues which could bite your parents on their butt. For example If your parents are on the loan but you are not then you would not want to do this for it could trigger a clause within the loan documents which would allow the bank to call the loan.
There are other items to investigate so speak with an attorney to make sure you are making the correct moves to seek your end result. To often agents have answers to questions but do not perform their diligence on the issue or issues at hand by asking questions.
Your parents will need to sign the document in the presence of a notary public.
James Sanchez has already given you the advice you need to proceed with the plan.
I could not add more as he already covered the steps, the repercussions and how the loan will not be affected should you decide to take your parents off the deed.
I should mention though that this requires your parents' consent or willingness to do so.