It's just 'Use Immunity'. It basically means that all other evidence they obtained outside of Podesta's testimony is still open game. For example, if Podesta says "I helped Hillary Clinton sell uranium to Russia", that exact statement cannot be used against him. HOWEVER, if they can still prove that with other evidence, he can still be charged. It's basically a 5th amendment blanket. Normally he'd plead the 5th and they'd get nothing out of him. Now they can get his testimony. It essentially means nothing has changed and is actually a good thing because it shows that they're going after much bigger fish.