Project description:Cell states are regulated by extrinsic signals from various external factors such as intercellular interactions, and intrinsic gene expression. Although comprehensive cell state profiling has been attempted, it remains simultaneous analysis of signal activation has still been challenging. Multiplexed imaging is a technique acquiring multiple protein information at a single cell level as traditional immunofluorescence. However, the method often compromises resolution, hindering the analysis of intracellular localization dynamics and post-translational modifications of proteins. To address these limitations, we developed an erasable fluorescence method using disulfide linkers to label antibodies. We term these antibodies ‘Precise Emission Canceling Antibodies (PECAbs)’. PECAb allows for high-resolution iterative imaging with minimal non-specific binding. Automation enables our system to achieve reproducible quantitative analysis using 206 antibodies. The resulting quantitative data allow reconstruction of the spatiotemporal dynamics of signaling pathways over both long and short timescales. Additionally, combining this approach with sequential RNA-FISH can effectively classify cells and identify their signal activation states in human tissue. Overall, the PECAb system serves as a comprehensive platform for analyzing complex cell processes, from signal transduction to gene expression.
Project description:Cell states are regulated by extrinsic signals from various external factors such as intercellular interactions, and intrinsic gene expression. Although comprehensive cell state profiling has been attempted, it remains simultaneous analysis of signal activation has still been challenging. Multiplexed imaging is a technique acquiring multiple protein information at a single cell level as traditional immunofluorescence. However, the method often compromises resolution, hindering the analysis of intracellular localization dynamics and post-translational modifications of proteins. To address these limitations, we developed an erasable fluorescence method using disulfide linkers to label antibodies. We term these antibodies ‘Precise Emission Canceling Antibodies (PECAbs)’. PECAb allows for high-resolution iterative imaging with minimal non-specific binding. Automation enables our system to achieve reproducible quantitative analysis using 206 antibodies. The resulting quantitative data allow reconstruction of the spatiotemporal dynamics of signaling pathways over both long and short timescales. Additionally, combining this approach with sequential RNA-FISH can effectively classify cells and identify their signal activation states in human tissue. Overall, the PECAb system serves as a comprehensive platform for analyzing complex cell processes, from signal transduction to gene expression.
Project description:During a minimally invasive tumor resection procedure, it is still a challenge to rapidly and accurately trace tiny malignant tumors in real time. Fluorescent molecular imaging is considered an efficient method of localizing tumors during surgery due to its high sensitivity and biosafety. On the basis of the fact that γ-glutamyltranspeptidase (GGT) is overexpressed in ovarian cancer, we herein designed a highly sensitive ratiometric fluorescent GGT-responsive probe Py-GSH for rapid tumor detection. Methods: The GGT response probe (Py-GSH) was constructed by using GSH group as a response group and pyrionin B as a fluorescent reporter. Py-GSH was characterized for photophysical properties, response speed and selectivity of GGT and response mechanism. The anti-interference ability of ratiometric probe Py-GSH to probe concentration and excitation power was evaluated both in vitro and in tissue. The biocompatibility and toxicity of the ratiometric probe was examined using cytoxicity test. The GGT levels in different lines of cells were determined by ratiometric fluorescence imaging and cytometry analysis. Results: The obtained probe capable to rapidly monitored GGT activity in aqueous solution with 170-fold ratio change. By ratiometric fluorescence imaging, the probe Py-GSH was also successfully used to detect high GGT activity in solid tumor tissues and small peritoneal metastatic tumors (~1 mm in diameter) in a mouse model. In particular, this probe was further used to determine whether the tissue margin following clinical ovarian cancer surgery contained tumor. Conclusion: In combination of ratiometric fluorescence probes with imaging instrument, a point-of-care imaging method was developed and may be used for surgical navigation and rapid diagnosis of tumor tissue during clinical tumor resection.
Project description:Elevated levels of bacteria, including biofilm, increase the risk of chronic wound infection and inhibit healing. Addressing asymptomatic high bacterial loads is challenged by a lack of clinical terminology and diagnostic tools. This post-hoc multicenter clinical trial analysis of 138 diabetic foot ulcers investigates fluorescence (FL)-imaging role in detecting biofilm-encased and planktonic bacteria in wounds at high loads. The sensitivity and specificity of clinical assessment and FL-imaging were compared across bacterial loads of concern (104 -109 CFU/g). Quantitative tissue culture confirmed the total loads. Bacterial presence was confirmed in 131/138 ulcers. Of these, 93.9% had loads >104 CFU/g. In those wounds, symptoms of infection were largely absent and did not correlate with, or increase proportionately with, bacterial loads at any threshold. FL-imaging increased sensitivity for the detection of bacteria across loads 104 -109 (P < .0001), peaking at 92.6% for >108 CFU/g. Imaging further showed that 84.2% of ulcers contained high loads in the periwound region. New terminology, chronic inhibitory bacterial load (CIBL), describes frequently asymptomatic, high bacterial loads in diabetic ulcers and periwound tissues, which require clinical intervention to prevent sequelae of infection. We anticipate this will spark a paradigm shift in assessment and management, enabling earlier intervention along the bacterial-infection continuum and supporting improved wound outcomes.
Project description:Molecular analysis of the effect left ventricular assist device (LVAD) support has on congestive heart failure patients. Keywords = Congestive heart failure, left ventricular assist device, eNOS, gene, dimethylarginine dimethylaminohydrolase Keywords: other