"With TB on the rise, this scenario could play out not only in cities in the United States but all over the world, " Prof Modlin said.

BBC: 'Wrong' immune response aids TB

Prof Robert Modlin, a dermatology and microbiology expert at the University of California, Los Angeles, said the study raises the possibility that a decrease or increase of one of these two proteins could shift the balance from mild to more serious disease.

BBC: 'Wrong' immune response aids TB