Fibroblast Activation Protein-Targeted PET/CT With Al18F-NODA-FAPI-04 for In Vivo Imaging of Tendon Healing in Rat Achilles Tendon Injury Models.

BACKGROUND: Fibroblast activation protein (FAP) has shown high expression in inflammatory responses and fibrosis. HYPOTHESIS: We speculated that FAP could serve as a diagnostic and monitoring target in the tendon healing process. STUDY DESIGN: Controlled laboratory study. METHODS: A total of 72 Sprague-Dawley rats were randomly divided into a tendon crush group and a half-partial tendon laceration group. Four rats in each group were injected with radiotracers weekly for 4 weeks after surgery, with aluminum fluoride-labeled 1,4,7-triazacyclononane-N,N',N″-triacetic acid-conjugated FAP inhibitor (Al18F-NODA-FAPI-04) administered on the first day of each week and 18F-fludeoxyglucose (18F-FDG) on the next day. Small animal positron emission tomography (PET) imaging was performed, and tendon tissue was collected for pathology and quantitative reverse transcription polymerase chain reaction (qRT-PCR) analysis each week after surgery. RESULTS: One week after surgery, both radiotracers showed signal concentration at the lesion site, which was the highest radioactive uptake observed during 4 weeks postoperatively, consistent with the severity of the lesion. Consistent trends were observed for inflammatory cytokines during qRT-PCR analysis. Additionally, Al18F-NODA-FAPI-04 PET exhibited a more precise lesion pattern, attributed to its high specificity for naive fibroblasts when referring to histological findings. Over time, the uptake of both radiotracers at the injury site gradually decreased, with 18F-FDG experiencing a more rapid decrease than Al18F-NODA-FAPI-04. In the fourth week after surgery, the maximum standardized uptake values of Al18F-NODA-FAPI-04 in the injured lesion almost reverted to the baseline levels, indicating a substantial decrease in naive fibroblasts and inflammatory cells and a reduction in inflammation and fibrosis, especially compared with the first week. Corresponding trends were also revealed in pathological and qRT-PCR results. CONCLUSION: Our findings suggest that inflammation is a prominent feature during the early stage of tendon injury. Al18F-NODA-FAPI-04 PET allows accurate localization and provides detailed morphological imaging, enabling continuous monitoring of the healing progress and assessment of injury severity.

Targeted glycan degradation potentiates cellular immunotherapy for solid tumors.

Immune cell-based cancer therapies, such as chimeric antigen receptor T (CAR-T)-cell immunotherapy, have demonstrated impressive potency against hematological tumors. However, the efficacy of CAR-T cells against solid tumors remains limited. Herein, we designed tumor-targeting molecule-sialidase conjugates that potently and selectively stripped different sialoglycans from a variety of cancer cells. Desialylation enhanced induced pluripotent stem cell-derived chimeric antigen receptor-macrophage (CAR-iMac) infiltration and activation. Furthermore, the combination of cancer cell desialylation and CAR-iMac adoptive cellular therapy exerted a dramatic therapeutic effect on solid tumors and significantly prolonged the survival of tumor-bearing mice; these effects were mainly dependent on blockade of the checkpoint composed of sialic acid-binding immunoglobulin-like lectin (Siglec)-5 and Siglec-10 on the macrophages, and knockout of the glycoimmune checkpoint receptors could construct a CAR-iMac cell with stronger anticancer activity. This strategy that reverts the immune escape state ("cold tumor") to a sensitive recognition state ("hot tumor") has great significance for enhancing the effect of cellular immunotherapy on solid tumors. Therefore, desialylation combined with CAR-iMac cellular immunotherapy is a promising approach to enhance treatment with cellular immunotherapy and expand the valid indications among solid tumors, which provides inspiration for the development of cellular immunotherapies with glycoimmune checkpoint inhibition for the treatment of human cancer.

[18F]AlF-NOTA-ADH-1: A new PET molecular radiotracer for imaging of N-cadherin-positive tumors.

Background: The cell adhesion molecule (CAM) N-cadherin has become an important target for tumor therapy. The N-cadherin antagonist, ADH-1, exerts significant antitumor activity against N-cadherin-expressing cancers. Methods: In this study, [18F]AlF-NOTA-ADH-1 was radiosynthesized. An in vitro cell binding test was performed, and the biodistribution and micro-PET imaging of the probe targeting N-cadherin were also studied in vivo. Results: Radiolabeling of ADH-1 with [18F]AlF achieved a yield of up to 30% (not decay-corrected) with a radiochemical purity of >97%. The cell uptake study showed that Cy3-ADH-1 binds to SW480 cells but weakly binds to BXPC3 cells in the same concentration range. The biodistribution results demonstrated that [18F]AlF-NOTA-ADH-1 had a good tumor/muscle ratio (8.70±2.68) in patient-derived xenograft (PDX) tumor xenografts but a lower tumor/muscle ratio (1.91±0.69) in SW480 tumor xenografts and lowest tumor/muscle ratio (0.96±0.32) in BXPC3 tumor xenografts at 1 h post-injection (p.i.) These findings were in accordance with the immunohistochemistry results. The micro PET imaging results revealed good [18F]AlF-NOTA-ADH-1 tumor uptake in pancreatic cancer PDX xenografts with strong positive N-calcium expression, while lower tumor uptake in SW480 xenografts with positive expression of N-cadherin, and significantly lower tumor uptake in BXPC3 xenografts with low expression of N-cadherin, which was consistent with the biodistribution and immunohistochemistry results. The N-cadherin-specific binding of [18F]AlF-NOTA-ADH-1 was further verified by a blocking experiment involving coinjection of a non radiolabeled ADH-1 peptide, resulting in a significant reduction in tumor uptake in PDX xenografts and SW480 tumor. Conclusion: [18F]AlF-NOTA-ADH-1 was successfully radiosynthesized, and Cy3-ADH-1 showed favorable N-cadherin-specific targeting ability by in vitro data. The biodistribution and microPET imaging of the probe further showed that [18F]AlF-NOTA-ADH-1 could discern different expressions of N-cadherin in tumors. Collectively, the findings demonstrated the potential of [18F]AlF-NOTA-ADH-1 as a PET imaging probe for non-invasive evaluation of the N-cadherin expression in tumors.

Kaempferol prevents acetaminophen-induced liver injury by suppressing hepatocyte ferroptosis via Nrf2 pathway activation.

Acetaminophen (APAP)-induced liver injury (AILI) has become a growing public health problem. Ferroptosis, an iron-dependent form of cell death associated with lipid peroxide accumulation, has been recently implicated in AILI. The activation of the Nrf2 signaling pathway is a potential therapy for AILI. Kaempferol (KA), a flavonoid widely existing in edible plants, has been reported to exert profound anti-inflammatory and antioxidant activities. This study aimed to investigate whether KA exerts anti-AILI effects via the Nrf2 signaling pathway. Mice were fasted for 22 h and injected intraperitoneally with APAP (250 mg kg-1) to induce AILI. Mice were pre-injected intragastrically with KA for 2 h followed by APAP injection. The hepatic injury was observed by H&E staining. Biochemical parameters of the serum and liver were measured using kits. KA alleviated hepatic injury and inflammatory response in AILI mice and ameliorated APAP-induced hepatic iron overload and oxidative stress in mice. In addition, the protective effects of KA against APAP-induced hepatotoxicity were examined in L02 cells in vitro. Cell viability was assayed by the CCK8 assay. Mitochondrial reactive oxygen species (ROS) in L02 cells were detected by MitoSox fluorescence. KA reversed the APAP-induced decrease in cell viability and GSH levels and inhibited the accumulation of intracellular ROS. Furthermore, KA activated the Nrf2 pathway and upregulated Gpx4 in mouse livers and L02 cells to inhibit ferroptosis induced by APAP. Finally, molecular docking indicated the potential interaction of KA with Keap1. Taken together, KA ameliorated oxidative stress and ferroptosis-mediated AILI by activating Nrf2 signaling.

Low frequency vibrating magnetic field-triggered magnetic microspheres with a nanoflagellum-like surface for cancer therapy.

BACKGROUND: The magneto-mechanical force killing cancer cells is an interesting and important strategy for cancer therapy. RESULTS: Novel magnetic microspheres composed of a Fe3O4 nanocore, a bovine serum albumin (BSA) matrix, and a rod-like SiO2 nanoshell, which had flagellum-like surface for force-mediated cancer therapy were developed. One such magnetic microsphere (Fe3O4/BSA/rSiO2) at a cancer cell (not leave the cell surface) under a low frequency vibrating magnetic field (VMF) could generate 6.17 pN force. Interestingly, this force could induce cancer cell to generate reactive oxygen species (ROS). The force and force-induced ROS could kill cancer cells. The cell killing efficiency of Fe3O4/BSA/rSiO2 exposed to a VMF was enhanced with increasing silica nanorod length, and the microspheres with straight nanorods exhibited stronger cell killing ability than those with curled nanorods. Fe3O4/BSA/rSiO2 triggered by a VMF could efficiently inhibit mouse tumor growth, while these microspheres without a VMF had no significant effect on the cell cycle distribution, cell viability, tumor growth, and mouse health. CONCLUSIONS: These microspheres with unique morphological characteristics under VMF have great potential that can provide a new platform for treating solid tumors at superficial positions whether with hypoxia regions or multidrug resistance.

Mitigating life cycle GHG emissions of roads to be built through 2030: Case study of a Chinese province.

The expansion of road networks in emerging economies such as China causes significant greenhouse gas (GHG) emissions. This development is conflicting with China's commitment to achieve carbon neutrality. Thus, there is a need to better understand life cycle emissions of road infrastructure and opportunities to mitigate these emissions. Existing impact studies of roads in developing countries do not address recycled materials, improved pavement maintenance, or pavement-vehicle interaction and electric vehicle (EV) adoption. Combining firsthand information from Chinese road construction engineers with publicly available data, this paper estimates a comprehensive account of GHG emissions of the road pavement network to be constructed in the next ten years in the Shandong province in Northern China. Further, we estimate the potential of GHG emission reductions achievable under three scenario sets: maintenance optimization, alternative pavement material replacement, and EV adoption. Results show that the life cycle GHG emissions of highways and Class 1-4 roads to be constructed in the next 10 years amount to 147 Mt CO2-eq. Considering the use phase in our model reveals that it is the dominant stage in terms of emissions, largely due to pavement-vehicle interaction. Vehicle electrification can only moderately mitigate these emissions. Other stages, such as materials production and road maintenance and rehabilitation, contribute substantially to GHG emissions as well, highlighting the importance of optimizing the management of these stages. Surprisingly, longer, not shorter maintenance intervals, yield significant emission reductions. Another counter-intuitive finding is that thicker and more material-intensive pavement surfaces cause lower emissions overall. Taken together, optimal maintenance and rehabilitation schedules, alternative material use, and vehicle electrification provide GHG reduction potentials of 11%, 4%-16% and 2%-6%, respectively.

Nanodrug-loaded Bifidobacterium bifidum conjugated with anti-death receptor antibody for tumor-targeted photodynamic and sonodynamic synergistic therapy.

Using bacteria for tumor-targeted therapy has attracted much attention in recent years. However, how to improve the targeted delivery and cancer therapy efficacy is an important but challenging scientific issue. Herein, a drug delivery system using a probiotic as a carrier was developed for tumor-targeted photodynamic and sonodynamic synergistic therapy. In this system, chlorin e6 (Ce6) nanoparticles (NPs) were prepared and incorporated into B. bifidum, followed by the conjugation of anti-death receptor 5 antibody (anti-DR5 Ab). Interestingly, B. bifidum under 671 nm laser or ultrasound (US) irradiation could generate reactive oxygen species (ROS), and Ce6-B. bifidum-anti-DR5 Ab obtained could target hypoxic regions in tumor with high efficiency after intravenous injection. The ROS level generated by Ce6-B. bifidum-anti-DR5 Ab under both laser and US irradiation was much higher than the combined ROS generated separately using a laser and US for the same probiotics. The cytotoxicity and laryngeal tumor growth-inhibiting efficiency of Ce6-B. bifidum-anti-DR5 Ab under both laser and US irradiation were significant higher than the values obtained using laser or US irradiation alone, which demonstrated the synergistic effect on tumor growth. B. bifidum could be eliminated from the body without exerting harmful effects on mouse health. This strategy is a platform that can be extended to treat other solid tumors. STATEMENT OF SIGNIFICANCE: Using bacteria as drug delivery carriers will show unique advantages. However, how to improve the targeted delivery efficiency and tumor inhibiting capacity is a challenging scientific issue. Herein, a delivery system using a probiotic as carrier was developed for tumor-targeted therapy. In this delivery system, chlorin e6 nanoparticles were prepared and then incorporated into living Bifidobacterium bifidum (B.bifidum), followed by the conjugation of anti-death receptor 5 antibody. This delivery system could efficiently target to mouse tumors, accumulate the hypoxic areas and inhibit the tumor growth through the photodynamic and sonodynamic synergistic effect. Our results will provide a platform for B.bifidum-mediated tumor targeted therapy.

Flexible ultrasonic array for breast-cancer diagnosis based on a self-shape-estimation algorithm.

Breast cancer is a very common malignant tumour that typically occurs in women aged 35-70 years (accounting for 85% of patients). Recently, it has been appearing in younger women as well. Traditional ultrasonic transducers usually use a fixed array, which avoids the radiation from mammography, has a low cost, and can be used for repeated testing. This substantially benefits the clinical diagnosis of breast cancer. However, the fixed transducer-array diagnosis process exerts considerable pressure on the human body, which can easily cause mass displacement or unnecessary pain. Therefore, ultrasound breast cancer diagnosis without compression has attracted attention. In this study, we used a flexible ultrasonic array to record the ultrasound information of the mass, and proposed a mathematical model suitable for breast-cancer diagnosis. Then, we used a self-shape-estimation algorithm to obtain a two-dimensional (2D) ultrasound image of the breast cancer. The algorithm was tested with simulated and experimental array data, and its performance was evaluated according to the tumour location. The surface-shape error obtained through the numerical simulation was less than 0.8 mm, and the deviation in the estimated mass position was less than 1.24 mm. The tumour location was also obtained experimentally in a breast-cancer model. Therefore, the method proposed in this paper can realize ultrasound diagnoses and represents a new diagnostic tool for breast cancer.