Gold Nanobipyramid-Mediated Apoptotic Camouflage of Adipocytes for Obesity Immunotherapy.

Obesity treatment is a global public health challenge due to the inadequate weight loss and weight regain even after endeavors with multimodal treatments. Considering abundant resident macrophages in adipose tissues, precise regulation of the interactions between macrophages and adipocytes may provide chances for immunotherapy of obesity. Herein, inspired by the phagocytosis of macrophages to clear apoptotic cells in homeostasis, an immunotherapy strategy for obesity treatment was proposed for the first time through apoptotic camouflage of adipocytes by PA Au BPs to activate macrophages for clearance, where PA Au BPs were gold nanobipyramids engineered with adipose-targeting and apoptotic cell-mimicking functions. During the clearance, macrophage was switched from pro-inflammatory M1 to anti-inflammatory M2, remarkably modulating the immune microenvironment of adipose tissues to prevent weight regain. After inguinal injection with PA Au BPs, the body weights of obesity mice were effectively decreased by 24.4%, and could be decreased by 33.3% when combined with photothermal lipolysis, and little weight regain was associated with treatments. This study demonstrates the strategy of camouflaging adipocytes with apoptotic feature holds great potential for obesity immunotherapy. This article is protected by copyright. All rights reserved.