Melo has struggled in his first season at Juve, but still did enough to earn selection in coach Dunga's provisional squad.
"Being called for a World Cup represents the realisation of a dream I had since I first started playing football," he said.
"I am very happy and want to celebrate with my family and loved ones. When Dunga gave me the opportunity to take part in some games, I made my presence felt, even if I know many are against my inclusion.
"I will go to South Africa convinced that I can give my contribution and hopeful the Brazilian people can come together in a unified sentiment with us to take the World Cup title back to our country."