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Abstract Cell and gene therapies hold tremendous promise for treating a range of difficult-to-treat diseases. However, concerns over the safety and efficacy require to be further addressed in order to realize their full potential. Synthetic receptors, a synthetic biology tool that can precisely control the function of therapeutic cells and genetic modules, have been rapidly developed and applied as a powerful solution. Delicately designed and engineered, they can be applied to finetune the therapeutic activities, i.e., to regulate production of dosed, bioactive payloads by sensing and processing user-defined signals or biomarkers. This review provides an overview of diverse synthetic receptor systems being used to reprogram therapeutic cells and their wide applications in biomedical research. With a special focus on four synthetic receptor systems at the forefront, including chimeric antigen receptors (CARs) and synthetic Notch (synNotch) receptors, we address the generalized strategies to design, construct and improve synthetic receptors. Meanwhile, we also highlight the expanding landscape of therapeutic applications of the synthetic receptor systems as well as current challenges in their clinical translation.

Abstract CRISPR‐based gene therapies are making remarkable strides toward the clinic. But the large size of most widely used Cas endonucleases including Cas9 and Cas12a restricts their efficient delivery by the adeno‐associated virus (AAV) for in vivo gene editing. Being exceptionally small, the recently engineered type V‐F CRISPR‐Cas12f1 systems can overcome the cargo packaging bottleneck and present as strong candidates for therapeutic applications. In this study, the pairwise editing efficiencies of different engineered Cas12f1/sgRNA scaffold combinations are systemically screened and optimized, and the CasMINI_v3.1/ge4.1 system is identified as being able to significantly boost the gene editing activity. Moreover, packaged into single AAV vectors and delivered via subretinal injection, CasMINI_v3.1/ge4.1 achieves remarkably high in vivo editing efficiencies, over 70% in transduced retinal cells. Further, the efficacy of this Cas12f1 system‐based gene therapy to treat retinitis pigmentosa in RhoP23H mice is demonstrated by the therapeutic benefits achieved including rescued visual function and structural preservation. And minimal bystander editing activity is detected. This work advances and expands the therapeutic potential of the miniature Cas12f1 system to support efficient and accurate in vivo gene therapy.

In the pursuit of precision medicine for cancer, a promising step is to predict drug response based on data mining, which can provide clinical decision support for cancer patients. Although some machine learning methods for predicting drug response from genomic data already exist, most of them focus on point prediction, which cannot reveal the distribution of predicted results. In this paper, we propose a three-layer feature selection combined with a gamma distribution based GLM and a two-layer feature selection combined with an ANN. The two regression methods are applied to the Encyclopedia of Cancer Cell Lines (CCLE) and the Cancer Drug Sensitivity Genomics (GDSC) datasets. Using ten-fold cross-validation, our methods achieve higher accuracy on anticancer drug response prediction compared to existing methods, with an R2 and RMSE of 0.87 and 0.53, respectively. Through data validation, the significance of assessing the reliability of predictions by predicting confidence intervals and its role in personalized medicine are illustrated. The correlation analysis of the genes selected from the three layers of features also shows the effectiveness of our proposed methods.

Abstract CRISPR-based nucleic acid detection methods are reported to facilitate rapid and sensitive DNA detection. However, precise DNA detection at the single-base resolution and its wide applications including high-fidelity SNP genotyping remain to be explored. Here we develop a Cas12b-mediated DNA detection (CDetection) strategy, which shows higher sensitivity on examined targets compared with the previously reported Cas12a-based detection platform. Moreover, we show that CDetection can distinguish differences at the single-base level upon combining the optimized tuned guide RNA (tgRNA). Therefore, our findings highlight the high sensitivity and accuracy of CDetection, which provides an efficient and highly practical platform for DNA detection.

Abstract Diploidy is the typical genomic mode in all mammals. Haploid stem cells are artificial cell lines experimentally derived in vitro in the form of different types of stem cells, which combine the characteristics of haploidy with a broad developmental potential and open the possibility to uncover biological mysteries at a genomic scale. To date, a multitude of haploid stem cell types from mouse, rat, monkey and humans have been derived, as more are in development. They have been applied in high-throughput genetic screens and mammalian assisted reproduction. Here, we review the generation, unique properties and broad applications of these remarkable cells.

Abstract CRISPR-Cas12a/Cpf1, a single RNA-guided endonuclease system, provides a promising tool for genome engineering. However, only three Cas12a orthologs have been employed for mammalian genome editing, and the editing efficiency as well as targeting coverage still requires improvements. Here, we harness six novel Cas12a orthologs for genome editing in human and mouse cells, some of which utilize simple protospacer adjacent motifs (PAMs) that remarkably increase the targeting range in the genomes. Moreover, we identify optimized CRISPR RNA (crRNA) scaffolds that can increase the genome editing efficiency of Cas12a.

Summary: Trophoblast stem (TS) cells are increasingly used as a model system for studying placentation and placental disorders. However, practical limitations of genetic manipulation have posed challenges for genetic analysis using TS cells. Here, we report the generation of mouse parthenogenetic haploid TS cells (haTSCs) and show that supplementation with FGF4 and inhibition of Rho-associated protein kinase (ROCK) enable the maintenance of their haploidy and developmental potential. The resulting haTSCs have 20 chromosomes, exhibit typical expression features of TS cells, possess the multipotency to differentiate into specialized trophoblast cell types, and can chimerize E13.5 and term placentas. We also demonstrate the capability of the haTSCs to undergo genetic manipulation and facilitate genome-wide screening in the trophoblast lineage. We expect that haTSCs will offer a powerful tool for studying functional genomics and placental biology. : Trophoblast stem (TS) cells are increasingly used as a model system for studying placentation and placental disorders. Here, Cui et al. report the generation of mouse haploid TS cells, which possess a wide extraembryonic developmental potential and can serve as a powerful tool for studying functional genomics and placental biology. Keywords: haploidy, trophoblast, stem cells, TSC