This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. This is a multi-center, single-blinded, randomized, placebo-controlled trial. Centers will screen 1200-1400 subjects and will randomize a total of 134 subjects over 3 years. The primary endpoint of this study is the effectiveness of B-cell depletion by anti-CD20 mAb therapy in reducing progression of chronic renal allograft dysfunction by chronic humoral rejection.