Macrophages participate in many links in the pathological process of atherosclerosis (AS) and the regulation of influence of macrophages at the molecular level might be a new avenue for AS treatment. For this aim, the macrophage membrane biomimetic nanoparticles, derived from macrophage membrane coated SHP1i-loaded liposome NPs (MM@Lips-SHP1i) was designed. Due to the reservation of intrinsic membrane proteins and function from macrophages, the biomimic nanoparticles could effectively evade clearance by the immune system, prolong blood circulation time and actively tend and aggregate to atherosclerotic plaques. More importantly, in the plaque area, MM@Lips-SHP1i nanoparticles could compete with macrophages in vivo to bind with oxidized low-density lipoprotein (oxLDL) and lipopolysaccharide (LPS), reduce uptake of new lipids by macrophages, reduce foam cell formation, and inhibit the expression of pro-inflammatory cytokines. In addition, small molecule inhibitor of SHP-1, the downstream effector molecule of CD47 loaded in macrophage membrane biomimetic nanoparticles could interrupt CD47-SIRPα signal transduction in monocytes and macrophages, thereby enhancing the efferocytosis of macrophages, inhibiting the progression of plaque, achieving synergistic treatment of atherosclerosis. This work focuses on the key process in the formation of AS, macrophage foaming and chronic inflammation, and is based on the fact that macrophage membrane biomimetic nanoparticles can preserve the key surface proteins of macrophages closely related to the formation of AS, providing a new avenue to inhibit the progression of AS by utilizing the biological characteristics of macrophage membrane in macrophage membrane biomimetic nanoparticles.
Yanjie Han,Haifeng Lu,Zikuan Gu,Peixin Guan,Zhen Liu
In situ reprogramming of tumor associated macrophages (TAMs) to resurge their phagocytic ability holds great potential in cancer treatment. However, most of currently existing TAMs-reshaping approaches fail to effectively reprogram TAMs due to low efficiency, poor specificity, and potential immune side effects. Herein, we report a strategy called molecularly imprinted lysosomal nanodegrader (MILND) for resurging the phagocytosis of macrophages and reversing the "don't eat me" CD47-SIRPα signal via degrading SIRPα in lysosomes. The MILND, which was rationally engineered by controllable molecular imprinting using the N-terminal epitope of SIRPα as template, could specifically bind SIPRα on TAMs. Upon being engulfed by TAMs via endocytosis, the MILND-SIRPα complex was transferred to lysosomes for degradation. The degradation of SIRPα induced a cascade reaction of the downstream PI3K signaling pathway to resurging the phagocytic and recognition capability of TAMs towards cancer cells. Ultimately, MILND resulted in a subsequent series of anti-tumor effects. Benefiting from this, MILND effectively sensitized the immune microenvironment and amplified CD8+ T cell responses, leading to substantial tumor growth inhibition in tumor-bearing mouse model. Thus, this work provides an efficient and versatile immunomodulatory strategy for enhanced antitumor immunotherapy.
Liu Chunlan,Yu Danxia,Ge Fuchun,Yang Limin,Wang Qiuquan
Ru(bpy) 3 @SiO 2 -COOH and Ru(bpy) 3 @SiO 2 @CD47-peptide nanoparticles (NPs) with fluorescent and mass spectrometric properties were designed and synthesized as the models of drug-nanocarriers. Their phagocytic internalization could be quantitatively measured using more sensitive inductively coupled plasma mass spectrometry (ICPMS) ( 102 Ru) versus traditional laser confocal scanning microscope ( λ ex/em = 458/600 nm) for the first time. Modification of a self-signal trigging CD47-peptide on the NPs’ surface decreased internalization by 10 times, (2.79 ± 0.21) × 10 4 Ru(bpy) 3 @SiO 2 -COOH and (0.28 ± 0.04) × 10 4 Ru(bpy) 3 @SiO 2 @CD47-peptide NPs per RAW264.7 macrophage ( n = 5). The alkynyl-linked CD47-peptide allowed us to quantify the number (2412 ± 250) of CD47-peptide modified on the NP and the total content (5.14 ± 0.25 amol) of signal regulatory protein α (SIRPα) on the macrophage by measuring the clickable tagged Eu using ICPMS. Furthermore, the interaction between CD47-peptide and SIRPα as well as the changes of the remaining free SIRPα during the internalization process of Ru(bpy) 3 @SiO 2 @CD47-peptide NPs were quantitatively evaluated, providing direct experimental evidence of the longspeculated crucial CD47-SIRPα interaction for drug-nanocarriers to escape internalization by phagocytic cells. Remarkable difference in the internalization ratio of 12.3 ± 4.8 of Ru(bpy) 3 @SiO 2 -COOH NPs and 4.3 ± 0.5 Ru(bpy) 3 @SiO 2 @CD47-peptide NPs with and without the protein corona indicated that CD47-peptide still worked when the protein corona formed. Not limited to the evaluation of the NPs studied here, such a fluorescent and mass spectrometric approach is very much expected to apply to the assessment of other drug-nanocarriers designed by chemists and before their medical applications.
Graphical abstract
危险品化学品经营许可证（带存储）