Biomedical subjects

Shuangshuang Yang

Publications and source records attributed to Shuangshuang Yang.

3 recordsLinked to original sources

PubMed2026

Efficient and precise programmable DNA knock-in without double-strand breaks.

Programmable gene knock-in holds substantial promise for treating genetic diseases and advancing cell therapies. However, achieving precise and efficient kilobase-scale DNA fragment integration remains challenging1,2. Here we report CRISPR kilobase-scale nickase-targeting (KNIT) editing for efficient, precise and programmable kilobase-scale DNA insertion without double-strand DNA cleavage, which is enabled through the coupling of a Cas9 nickase with a DNA donor recruiting system. KNIT editing facilitates programmable integration of DNA fragments from 0.7 kb to more than 10 kb and is effective across genomic loci and cell types. It achieves up to 89% efficiency and markedly reduces unintended insertion-deletion mutation (indels) rates, translocations and off-target editing. The system supports repeated insertion editing and multiloci gene knock-in with minimal translocations. Its enhanced version, KNIT editor 2, further improves efficiency via a single transfection. Moreover, in mutant cells with a pathological mutation, KNIT editing restores normal gene expression by inserting a therapeutic gene into a safe harbour locus or its native locus. Notably, KNIT editing enables non-viral and programmable chimeric antigen receptor T cell (CAR-T cell) engineering without double-strand breaks and with clinically relevant efficiencies. Moreover, the engineered CAR-T cells exhibit effective antitumour activity in vitro and in mouse models. Therefore, by achieving programmable and site-specific kilobase-scale DNA insertions without double-strand breaks while reducing unintended outcomes, KNIT editing provides a versatile platform for advancing personalized medicine.

Animals↗

PubMed2025

High Hcy regulates fluid shear stress pathway activity through histone H3K79 homocysteinylation in hyperhomocysteinemia-related child hypertension.

BACKGROUND: The rise of hypertension in children has been increasingly associated with hyperhomocysteinemia (HHcy), which is recognized as a major risk factor. However, the underlying mechanisms linking homocysteine and hypertension (termed HHYP) are not fully understood. METHODS: This study utilized plasma samples from 27 control children and 27 children with HHYP (aged 8 ~ 16 years) for TMT6-labeled proteomic quantification, identifying significant altered proteins. Bioinformatics analysis revealed pathway alterations. Verification was carried out via parallel reaction monitoring (PRM) and western blot (WB) analyses. Additionally, a rat model of HHYP induced by high methionine diets, and umbilical vein endothelial cell models exposed to high homocysteine (hcy) levels were developed to investigate the molecular underpinnings further. Protein expression changes and epigenetic modifications were assessed using WB, immunohistochemistry (IHC), and ChIP-qPCR techniques. RESULTS: Key findings indicated that 357 proteins and 69 pathways were altered in children with HHYP. Specifically, 12 proteins within the fluid shear stress and atherosclerosis (FSSA) pathway showed differential expression, including the downregulation of TRX1 and GPX1 and the upregulation of ICAM1. The same expression patterns were noted in both the HHYP rat aortic tissues and the high hcy cultured endothelial cells. Moreover, elevated H3K79hcy modification levels were observed alongside epigenetic regulation of genes related to the FSSA pathway. Importantly, folic acid (FA), a medication frequently used in the clinical treatment of HHYP, has been demonstrated to effectively reverse H3K79hcy modifications and restore the disrupted FSSA pathway in both animal models and cell cultures. CONCLUSIONS: The present study suggests that HHcy may contribute to hypertension through the epigenetic dysregulation of the FSSA pathway mediated by H3K79hcy. Furthermore, the pediatric proteomics data gleaned from this study offer new clinical insights into the pathophysiology of HHYP in children.

Hyperhomocysteinemia↗

PubMed2022

An epithelial-immune circuit amplifies inflammasome and IL-6 responses to SARS-CoV-2.

Elevated levels of cytokines IL-1β and IL-6 are associated with severe COVID-19. Investigating the underlying mechanisms, we find that while primary human airway epithelia (HAE) have functional inflammasomes and support SARS-CoV-2 replication, they are not the source of IL-1β released upon infection. In leukocytes, the SARS-CoV-2 E protein upregulates inflammasome gene transcription via TLR2 to prime, but not activate, inflammasomes. SARS-CoV-2-infected HAE supply a second signal, which includes genomic and mitochondrial DNA, to stimulate leukocyte IL-1β release. Nuclease treatment, STING, and caspase-1 inhibition but not NLRP3 inhibition blocked leukocyte IL-1β release. After release, IL-1β stimulates IL-6 secretion from HAE. Therefore, infection alone does not increase IL-1β secretion by either cell type. Rather, bi-directional interactions between the SARS-CoV-2-infected epithelium and immune bystanders stimulates both IL-1β and IL-6, creating a pro-inflammatory cytokine circuit. Consistent with these observations, patient autopsy lungs show elevated myeloid inflammasome gene signatures in severe COVID-19.

Humans↗