Figure 1.

Schematic of the dual-sized microparticle (dMP) system. The dMP formulation is an injectable platform that provides sustained extracellular release of a DC chemokine, GM-CSF, and a protolerogenic factor, TGF-β1, via ∼30 μm nonphagocytosable MPs to recruit and condition DCs at a subcutaneous injection site. Concurrently, ∼1 μm phagocytosable MPs encapsulating antigen, denatured insulin, and a tolerizing agent, vitamin D₃, provide targeted intracellular delivery to the locally recruited DCs in order to promote presentation of the T1D autoantigen in a tolerogenic context.