The present invention relates to αv&bgr;8 antagonists, anti-αv&bgr;8 antibodies or immunoconjugates for reducing TGF&bgr; activation in an individual. Further provided are compositions comprising one of the αv&bgr;8 antagonists, anti-αv&bgr;8 antibodies or immunoconjugates, methods for using the compositions, and related subject matter.