单标志物不够，微环境还爱干扰#

巨噬细胞向泡沫细胞转化是动脉粥样硬化早期事件，但常规影像看到的是已形成斑块，难以定量追踪不同阶段。miRNA或活性氧单标志物探针又容易受细胞类型和氧化微环境干扰。作者把次氯酸（HClO）和miR-214做成双输入AND门，只有两者同时升高才点亮荧光，试图提高泡沫细胞成像的选择性并分辨阶段。

Fig.1 Characterization of TPCM nanoprobe. (A) PAGE analysis of the stepwise assembly of TP and TPCM. (B) AFM image of TPCM. Scale bar: 400 nm. (C) Cross-sectional height profile along the white line indicated in (B). (D) TEM image of TPCM. Scale bar: 100 nm. Inset: particle size distribution histogram (n = 50). (E) PAGE analysis of TPCM (2 μM) stability following incubation in 10% serum at room temperature for the indicated time intervals. (F) Confocal fluorescence images of RAW 264.7 macrophages incubated with TPCM for 0.5, 1, 2, 4, 6, and 8 h. Scale bar: 50 μm.

三角棱柱把反应加快2.52倍#

TPCM由8条核酸链组装，AFM高约0.59 nm、TEM直径12–16 nm，10%血清中至少4 h保持完整，RAW 264.7摄取4 h接近平衡、Cy5阳性细胞超过89%。单链和组装体都只在HClO与miR-214同时存在时出现超过70%荧光恢复，单输入几乎无信号。刚性支架使催化平衡从约180 min缩短到90 min，kobs从0.0132升至0.0334 min⁻¹，约2.52倍。检测线性范围：HClO 0.1–1.0 μM、LOD 0.082 μM；miR-214 1.0–50 nM、LOD 0.81 nM；其他miRNA和ROS/RNS干扰很小。用20、40、60 μg/mL ox-LDL造泡沫细胞阶段，TPCM荧光随剂量升高，并与脂滴、MPO活性、miR-214及MMP-9/ITGβ1升高一致；HEK293T、HepG2、MAEC和LPS炎症巨噬细胞几乎无信号。ABAH（0.5 mM）和Calphostin C（300 nM）处理后信号下降，CCK-8显示细胞活力高于80%。

Fig.2 TPCM enables stage-resolved imaging of foam cell progression. (A) Schematic illustration of RAW 264.7 macrophage treatment with varying ox-LDL concentrations (0, 20, 40, and 60 μg/mL) to model distinct extents (early-, middle-, and advanced-stage) of lipid accumulation in foam cells. (B) CLSM images and (C) corresponding quantitative mean Cy5 fluorescence intensities of macrophages following a 4 h incubation with 300 nM TPCM. Scale bar: 50 μm. (D) Flow cytometry analysis of the corresponding treatment groups. (E) Western blot analysis and (F) relative quantification of MMP-9 and ITGβ1 expression, using β-actin as the internal loading control. Data are presented as mean ± SD (n = 3). Statistical significance was determined by one-way ANOVA. ns, not significant, *P < 0.05, **P < 0.01, ***P < 0.001.

Fig.3 TPCM enables monitoring therapeutic interventions of foam cells. (A) Schematic illustration of inhibitor treatments (ABAH or Cal) on ox-LDL-induced foam cells. (B) CLSM images and (C) corresponding quantitative mean Cy5 fluorescence intensities of foam cells following inhibitor treatments. ABAH: 0.5 mM; Cal: 300 nM. Scale bar: 60 μm. (D) Flow cytometry analysis of the corresponding treatment groups. (E) Western blot analysis and (F) relative quantification of MMP-9 and ITGβ1 expression, using β-actin as the internal loading control. Data are presented as mean ± SD (n = 3). Statistical significance was determined by one-way ANOVA. ns, not significant, *P < 0.05, **P < 0.01, ***P < 0.001.

是细胞筛选工具，还不是在体影像#

理论上，这把“双标志物AND门＋DNA三角棱柱空间限制”做成提高特异性和动力学的手段，证明在细胞模型中可区分ox-LDL诱导的不同阶段并监测药物抑制。做动脉粥样硬化体外机制、药物筛选或DNA逻辑探针的人，可以用它比较HClO和miR-214同时升高的细胞状态，减少非靶细胞假阳性。边界也清楚：全部证据来自细胞模型，所谓阶段由ox-LDL浓度模拟，不等于人体病理分期；没有在体斑块成像、动物药代和长期毒性数据；探针依赖细胞内Mg²⁺激活DNAzyme，血清稳定只测到4 h。原文未提供直接临床或在体转化证据。它目前是有机制验证的细胞分析工具，不是现成诊断探针。