Immunotherapy via PD-L1-presenting biomaterials leads to long-term islet graft survival. - Coronel MM; Martin KE; Hunckler MD; Barber G; O'Neill EB; Medina JD; Opri E; McClain CA; Batra L; Weaver JD; Lim HS; Qiu P; et al. (Science advances, 2020)