CD34 and thromboangiitis obliterans: This study focuses on the use of poly(lactic-co-glycolic) acid (PLGA)-based microspheres (MS) coupled with CD34-specific aptamers to enhance the targeted delivery of Tocilizumab (Toc), an IL-6 receptor monoclonal antibody, to CD34+ orbital fibroblasts, which is a critical cell type implicated in TAO.