CRISPR-based molecular diagnostics: a review / 生物工程学报

Rapid and accurate detection technologies are crucial for disease prevention and control. In particular, the COVID-19 pandemic has posed a great threat to our society, highlighting the importance of rapid and highly sensitive detection techniques. In recent years, CRISPR/Cas-based gene editing technique has brought revolutionary advances in biotechnology. Due to its fast, accurate, sensitive, and cost-effective characteristics, the CRISPR-based nucleic acid detection technology is revolutionizing molecular diagnosis. CRISPR-based diagnostics has been applied in many fields, such as detection of infectious diseases, genetic diseases, cancer mutation, and food safety. This review summarized the advances in CRISPR-based nucleic acid detection systems and its applications. Perspectives on intelligent diagnostics with CRISPR-based nucleic acid detection and artificial intelligence were also provided.

Potent SARS-CoV-2 neutralizing antibodies selected from a human antibody library constructed decades ago

Combinatorial antibody libraries not only effectively reduce antibody discovery to a numbers game, but enable documentation of the history of antibody responses in an individual. The SARS-CoV-2 pandemic has prompted a wider application of this technology to meet the public health challenge of pandemic threats in the modern era. Herein, we used a combinatorial human antibody library constructed 20 years before the COVID-19 pandemic to discover three highly potent antibodies that selectively bind SARS-CoV-2 spike protein and neutralize authentic SARS-CoV-2 virus. Compared to neutralizing antibodies from COVID-19 patients with generally low somatic hypermutation (SHM), these antibodies contain over 13-22 SHMs, many of which are involved in specific interactions in crystal structures with SARS-CoV-2 spike RBD. The identification of these somatically mutated antibodies in a pre-pandemic library raises intriguing questions about the origin and evolution of human immune responses to SARS-CoV-2.

MITOCHONDRIAL CHANGES AND THEIR REGULATION INMURINE APOPTOTIC PERITONEAL MACROPHAGE / 解剖学报

Objective To study the changes in activity of NADPH oxidase, the effects of signal molecules on membrane potential and ROS production of mitochondria in apoptotic murine peritoneal macrophages. Methods Laser scanning confocal microscopy, flow cytometry and fluorescence labeling were used. Results 1 The macrophages treated with dexamethasone developed apoptosis quickly and presented concomitant apoptotic changes. 2 Mitochondria membrane depolarized quickly, the activity of NADPH oxidase declined sharply, and ROS production decreased rapidly. The erasers of ROS promoted macrophage apoptosis. 3 PKC favored, and cAMP inhibited the macrophage apoptosis and the rapid drop in ROS and mitochondrial membrane depolarization. cGMP and TPK which slightly inhibited macrophage apoptosis, had no effects on ROS. Conclusion 1 The activity of NADPH oxidase declined sharply, hence the ROS decreased rapidly, which promoted apoptosis in macrophages treated with dexamethasone. 2 The signal molecules affected apoptosis by modulating ROS decline and mitochondria depolarization. The results suggested that, mitochondria variations, especially the variations of ROS and membrane potential, mainly affected macrophage apoptosis.;