Uveitis is a severe inflammatory disease that can cause visual impairment. Recently, activated γδ T cells were proved to play a central role in the development of experimental autoimmune uveitis (EAU). However, the mechanism underlying γδ T-cell activation in EAU is incompletely known. In this study, we determined the percentage changes in and the phenotypes of γδ T cells and dendritic cells (DCs) obtained from the spleens of immunized C57BL/6 (B6) mice, an animal model of EAU. We found that the number of γδ T cells and DCs obviously increased during the inflammation phase of EAU (days 16–20 of our experiment), and that during this time, γδ T cells expressed high levels of CD69 and the integrin lymphocyte function–associated antigen-1 (LFA-1) and secreted high levels of interleukin (IL)-17A. Moreover, DCs obtained during this phase expressed high levels of CD80, CD83, CD86, and intracellular cell adhesion molecule-1 (ICAM-1). Furthermore, we studied the interaction between DCs and T cells by using flow cytometry and confocal microscopy in order to determine whether DCs affected γδ T-cell activation in vitro. Co-cultures of the two types of cells showed that DCs induced high levels of CD69, LFA-1, and IL-17A in γδ T cells. Imaging studies revealed contact between the DCs and γδ T cells. This interaction was mediated by the accumulation of ICAM-1 and LFA-1 at the interface of DCs-γδ T cells. Thus, the activation of γδ T cells in EAU was promoted by DCs interacting with γδ T cells.

Integrins, over-expressed in a broad range of cancer diseases, are widely utilized as a tumor biomarker. Metabolism investigation also plays important roles in tumor theranostics. Developing simple integrin-targetting probe and monitoring tumor metabolism will give opportunities to find ways for cancer treatment, however, the investigation of tumor metabolism with integrin receptor based probes has been rarely reported so far. Here, we developed an octavalent fluorescent probe Octa-RGD by convenient genetic method, based on one tetrameric far-red fluorescent protein (fRFP) linked with RGD peptides. We validated its intergin targeting by confocal imaging in vitro. Then we screened a variety of tumor cells, and differentiated their binding affinity based on the fluorescence of the probe via flow cytometry. Among these cells, CNE-2 cells had the highest uptake of the probe, while B16 cells had the lowest, corresponding with their intergin expression levels. Next, the fluorescent and metabolic imaging was performed in HT1080 (intergin postive) tumor, where nicotinamide adenine dinucleotide hydrogen (NADH), flavoprotein (Fp) and fRFP fluorescent signals were collected. The tumor from mice intravenously injected with Octa-RGD probe displayed obviously higher NADH redox ratio NADH/ (FptNADH) and fRFP signal, than those with fRFP protein. It suggested that integrin targeting may have influence on the target cell metabolism, and further demonstrated Octa-RGD probe facilitated its uptake in the targeted tumor in vivo. This paper developed a useful probe, which can bind integrins specifically and efficiently in tumor cells, and together with tumor metabolic information, it may provide new insight for RGD targeting-based cancer therapeutics.

研究了偶联环状精氨酸-甘氨酸-天冬氨酸-D-苯丙氨酸-赖氨酸[c(RGDfK)]肽段的CdSe/ZnS量子点(QD-RGD)对喉癌血管靶向成像。利用羧基与氨基反应将c(RGDfK)肽段与QD偶联；采用荧光分光光度计对QD-RGD在RMPI1640培养基和小鼠血清溶液中的光谱稳定性进行了检测；利用荧光显微镜检测QD-RGD对Hep-2细胞和MCF-7细胞上整合素αvβ3的靶向性；最后将QD-RGD尾静脉注射到小鼠体内，检测了其对皮脊翼视窗中喉癌血管的靶向性。结果表明QD-RGD的发射光谱在RMPI1640培养基4 h内没有明显变化，在小鼠血清中24 h内发射光谱的荧光强度仅下降了20%；对细胞荧光成像表明QD-RGD能特异性与细胞表面的整合素αvβ3结合；血管成像表明QD-RGD 在注射2 h后聚集在喉癌局部血管，24 h 后QD-RGD从血管中移除。该研究表明QD-RGD能用于活体喉癌肿瘤血管靶向成像，这为喉癌的靶向诊断和靶向治疗研究提供了参考。

肿瘤靶向治疗的研究是当今生物医学界的研究热点。寻找具有肿瘤靶向性的高效体内运输载体是实现肿瘤靶向治疗的关键。采用整合素αvβ3单克隆抗体作为肿瘤靶向分子, 以单壁碳纳米管(SWNT)作为运输载体, 通过碳纳米管表面的适当功能化, 将整合素αvβ3单抗标记在碳纳米管上, 构建整合素αvβ3单抗标记的碳纳米管新型肿瘤靶向探针; 研究探针在人脐静脉内皮细胞HUVEC和整合素αvβ3高表达的人脑神经胶质瘤细胞U87MG的肿瘤靶向性。实验结果表明, 这种整合素αvβ3单抗标记的碳纳米管探针对U87MG细胞靶向选择性高, 将能成为一种有潜力的药物输送及肿瘤分子影像的新型肿瘤靶向载体。