Abstract
Regulatory T (Treg) cells underlie multiple autoimmune disorders and potentialize an anti-inflammation treatment with adoptive cell therapy. However, systemic delivery of cellular therapeutics often lacks tissue targeting and accumulation for localized autoimmune diseases. Besides, the instability and plasticity of Treg cells also induce phenotype transition and functional loss, impeding clinical translation. Here, we developed a perforated microneedle (PMN) with favorable mechanical performance and a spacious encapsulation cavity to support cell survival, as well as tunable channels to facilitate cell migration for local Treg therapy of psoriasis. In addition, the enzyme-degradable microneedle matrix could release fatty acid in the hyperinflammatory area of psoriasis, enhancing the Treg suppressive functions via the fatty acid oxidation (FAO)-mediated metabolic intervention. Treg cells administered through PMN substantially ameliorated psoriasis syndrome with the assistance of fatty acid-mediated metabolic intervention in a psoriasis mouse model. This tailorable PMN could offer a transformative platform for local cell therapy to treat a variety of diseases.