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关键词： cell main spectra   circulating tumour cell   MALDI-TOF   method development  

摘要： Simple Summary Cancer cells can detach from a primary tumour and present in peripheral blood as circulating tumour cells, or in the widest sense, as circulating atypical cells (CAC). Although CAC are a promising biomarker for non-invasive cancer screening, they occur at very low frequency and their detection and characterization remains challenging. We here validated isolation and concentration of untouched CAC from spiked cancer cell blood samples and combined this with matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS). This workflow was optimised to detect as little as six cancer cells per 5000 white blood cells. Future development of our workflow may cover a larger range of cancer types and further improvements to enable the use of MALDI-TOF MS as a cancer-screening platform in clinical settings. Circulating atypical cells (CAC) are released from a primary tumour site into peripheral blood and are indicators of cancer metastasis. CAC occur at very low frequency in circulating blood, and their detection remains challenging. Moreover, white blood cells (WBC) are the major contaminant in enriched CAC samples. Here, we developed matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) as a novel CAC characterization platform. Main spectra profiles (MSP) of normal and cancer cells were generated by MALDI-TOF MS, and a cell-main spectra database was then compiled and analysed using the MALDI Biotyper software. Logarithmic scores accurately predicted distinct cell types. The feasibility of this workflow was then validated using simulated samples, which were prepared by 5000 WBC of three healthy individuals spiked with varying numbers (3, 6, 12, 25, 50, and 100) of lung, colon, or prostate cancer cells. MALDI-TOF MS was able to detect cancer cells down to six cells over the background noise of 5000 WBC with significantly higher predictive scores as compared to WBC alone. Further development of c

关键词： Crystal structure   Citrate synthase   Hymenobacter sp   PAMC 26554   Domain movement   X-ray crystallography  

摘要： Citrate synthase (CS) catalyzes the formation of citrate and coenzyme A from acetyl-CoA and oxaloacetate. CS exists in two forms: type I and type II. We determined the citrate-bound crystal structure of type II CS from the Hymenobacter sp. PAMC 26554 bacterium (HyCS;isolated from Antarctic lichen). Citrate molecules bound to a cleft between the large and small domains of HyCS. Structural comparison of HyCS with other type II CSs revealed that type II CSs have a highly conserved flexible hinge region (residues G264-P265 in HyCS), enabling correct positioning of active site residues. Notably, the catalytic His266 residue of HyCS interacted with Trp262 in the inactive (unliganded open) state of other type II CSs, whereas the His266 residue moved to the active site via a small-domain swing motion, interacting with the bound citrate in the closed conformation of HyCS. However, type I CSs lack this tryptophan residue and face-to-edge interactions. Thus, type II CSs might have a unique domain-motion control mechanism enabling a tight allosteric regulation. An activity assay using a W262A mutant showed a Hill coefficient of 2.4;thus, the interaction between Trp262 and His266 was closely related to the positive cooperative ligand binding of type II CS. (c) 2021 Published by Elsevier B.V.

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摘要： Objective. To investigate the clinical effect of iodine-125 seed implantation combined with chemotherapy in patients with primary liver cancer and the effect on peripheral blood Th1/Th2 cells. Methods. A total of 136 patients with primary liver cancer from April 2017 to June 2018 were selected as subjects and randomly divided into the control group and observation group with 68 cases in each group. The control group was treated with chemotherapy, and the observation group was treated with iodine-125 seed implantation on the basis of the control group. After 3 months of treatment, the curative effect was investigated. Serum tumor markers, peripheral blood Th1/Th2 cells, and side effects and recurrence rate were compared between the two groups. Results. The levels of serum tumor markers in both groups at 3 months after treatment were lower than before treatment (P<0.05). Three months after treatment, the levels of tumor markers AFP, AFP-L3, and GP73 in the observation group were 14.61 +/- 3.49 mu g/L, 3.29 +/- 0.41 ng/mL, and 51.24 +/- 4.51 mu g/L, respectively, which were lower than those in the control group, 32.53 +/- 4.59 mu g/L, 5.63 +/- 0.63 ng/mL, and 71.52 +/- 6.05 mu g/L (P<0.05). At 3 months after treatment, the level of including interleukin-2 (IL-2) and tumor necrosis factor-alpha (TNF-alpha) in Th1 cells of the observation group was higher than that of the control group (P<0.05), whereas the levels of IL-4, IL-6, and IL-10 in Th2 cells were lower than those in the control group (P<0.05). There was no statistical significance in the incidence of leukopenia, thrombocytopenia, and gastrointestinal reactions between the two groups (P>0.05). The recurrence rate of the observation group at 12, 24, and 36 months after treatment was lower than that of the control group (P<0.05). Conclusion. Iodine-125 seed implantation combined with chemotherapy in patients with primary liver cancer can reduce the level of serum tumor markers, improve the level of peripheral bloo

关键词： artificial antigen-presenting cells   cancer immunotherapy   intracellular hydrogelation   radical polymerization   T-cell expansion  

摘要： Robust and modular systems for T cell expansion have immense utilities for clinical development and immunoengineering research. In article 2101190, Che-Ming J. Hu and co-workers demonstrate a photoactivated intracellular radical polymerization technique that transforms live dendritic cells into a functional T-cell-stimulating biomaterial, which effectively enhances adoptive cell therapy against cancer in mice.

关键词： intracellular trafficking   endosomal maturation   confocal Raman microscopy   hyperspectral imaging   near-infrared fluorescence   machine learning   immunofluorescence colocalization  

摘要： Intracellular vesicle trafficking involves a complex series of biological pathways used to sort, recycle, and degrade extracellular components, including engineered nanomaterials (ENMs) which gain cellular entry via active endocytic processes. A recent emphasis on routes of ENM uptake has established key physicochemical properties which direct certain mechanisms, yet relatively few studies have identified their effect on intracellular trafficking processes past entry and initial subcellular localization. Here, we developed and applied an approach where single-walled carbon nanotubes (SWCNTs) play a dual *** of an ENM undergoing intracellular processing, in addition to functioning as the signal transduction element reporting these events in individual cells with single organelle resolution. We used the exceptional optical properties exhibited by noncovalent hybrids of single-stranded DNA and SWCNTs (DNA-SWCNTs) to report the progression of intracellular processing events via two orthogonal hyperspectral imaging approaches of near-infrared (NIR) fluorescence and resonance Raman scattering. A positive correlation between fluorescence and G-band intensities was uncovered within single cells, while exciton energy transfer and eventual aggregation of DNA-SWCNTs were observed to scale with increasing time after internalization. An analysis pipeline was developed to colocalize and deconvolute the fluorescence and Raman spectra of subcellular regions of interest (ROIs), allowing for single-chirality component spectra to be obtained with submicron spatial resolution. This approach uncovered correlations between DNA-SWCNT concentration, dielectric modulation, and irreversible aggregation within single intracellular vesicles. An immunofluorescence assay was designed to directly observe the DNA-SWCNTs in labeled endosomal vesicles, revealing a distinct relationship between the physical state of organelle-bound DNA-SWCNTs and the dynamic luminal conditions during endosomal