Biology subjects

Ling, Y.

Publications and source records attributed to Ling, Y..

23 records · Page 2Linked to original sources

bioRxiv2020

Large-scale single-cell analysis reveals critical immune characteristics of COVID-19 patients

Dysfunctional immune response in the COVID-19 patients is a recurrent theme impacting symptoms and mortality, yet the detailed understanding of pertinent immune cells is not complete. We applied single-cell RNA sequencing to 284 samples from 205 COVID-19 patients and controls to create a comprehensive immune landscape. Lymphopenia and active T and B cell responses were found to coexist and associated with age, sex and their interactions with COVID-19. Diverse epithelial and immune cell types were observed to be virus-positive and showed dramatic transcriptomic changes. Elevation of ANXA1 and S100A9 in virus-positive squamous epithelial cells may enable the initiation of neutrophil and macrophage responses via the ANXA1-FPR1 and S100A8/9-TLR4 axes. Systemic upregulation of S100A8/A9, mainly by megakaryocytes and monocytes in the peripheral blood, may contribute to the cytokine storms frequently observed in severe patients. Our data provide a rich resource for understanding the pathogenesis and designing effective therapeutic strategies for COVID-19. HIGHLIGHTSO_LILarge-scale scRNA-seq analysis depicts the immune landscape of COVID-19 C_LIO_LILymphopenia and active T and B cell responses coexist and are shaped by age and sex C_LIO_LISARS-CoV-2 infects diverse epithelial and immune cells, inducing distinct responses C_LIO_LICytokine storms with systemic S100A8/A9 are associated with COVID-19 severity C_LI

genomics↗

bioRxiv2020

A putative long noncoding RNA-encoded micropeptide maintains cellular homeostasis in pancreatic β-cells

Micropeptides (microproteins) encoded by transcripts previously annotated as long noncoding RNA (IncRNAs) are emerging as important mediators of fundamental biological processes in health and disease. Here we applied two computational tools to identify putative micropeptides encoded by lncRNAs that are expressed in the human pancreas. We experimentally verified one such micropeptide encoded by a {beta}-cell- and neural cell-enriched lncRNA TUNAR (also known as TUNA, HI-LNC78 or LINC00617). We named this highly conserved 48-amino-acid micropeptide Beta cell- and Neural cell-regulin (BNLN). BNLN contains a single-pass transmembrane domain and localized at the endoplasmic reticulum in pancreatic {beta}-cells. Overexpression of BNLN lowered ER calcium levels, increased cytosolic calcium levels, and maintained ER homeostasis in response to high glucose challenge. To determine the physiological and pathological roles of BNLN, we assessed the BNLN expression in islets from mice fed with a high-fat diet and a regular diet, and found that BNLN is suppressed by diet-induced obesity (DIO). Conversely, overexpression of BNLN elevated glucose-stimulated insulin secretion in INS-1 cells. Lastly, BNLN overexpression enhanced insulin secretion in islets from lean and obese mice as well as from humans. Taken together, our study provides the first evidence that lncRNA-encoded micropeptides play a critical role in pancreatic {beta}-cell function and provides a foundation for future comprehensive analyses of micropeptide function and pathophysiological impact on diabetes.

molecular biology↗

bioRxiv2019

Antibody Bank: the Synthetic Cell Repertoire for Immunotherapy

The immune surveillance hypothesis is regarded as the intellectual underpinning of cancer immunology. We find that engineered T cell library displaying CAR constructs, where the antibody repertoires took the place of the antigen-recognition region, has the capacity to recognize nonself-antigens and showed antigen dependent clonal expanding and persistence. This process coupled with long-lasting anti-tumour effect in a broad spectrum of epithelial tumours. Moreover, CAR-T library showed robust immunologic memory and maintenance of diversity to recognize mutated or evolved tumours in both immunodeficiency and immunoresponsive murine tumor models. Large CAR library was further developed in logic-gated NK-92 cells to develop an off-the shelf therapeutic library. Thus, the biological behaviour of synthetic cell library is highly accordance with the immune surveillance function, which proved the way to rebuilt functional MHC unrestricted cellular immunity in vitro using synthetic method.

bioengineering↗

bioRxiv2019

Targeted mRNA demethylation using an engineered dCas13b-ALKBH5 fusion protein

Studies on biological functions of N6-methyladenosine (m6A) modification in mRNA have sprung up in recent years. Here we construct and characterize a CRISPR-Cas13b-based tool for the first time that targeted m6A methylation of mRNA by fusing the catalytically dead Type VI-B Cas13 enzyme from Prevotella sp.P5-125 (dPspCas13b) with the m6A demethylase ALKBH5, which is named as dm6ACRISPR. Subsequently, such system is shown to specific demethylase the m6A of target mRNA such as CYB5A to increase its mRNA stability. In addition, the dm6ACRISPR system appeared to afford efficient demethylation of the target genes with tenuous off-target effects. Together, we provide a programmable and in vivo manipulation tool to study mRNA modification and its potential biological functions of specific gene.

cell biology↗

bioRxiv2019

Treatment of Murine Lupus with TIGIT-Ig

The TIGIT (T cell immunoreceptor with Ig and ITIM domains) protein is a co-inhibitory receptor that has been reported to suppress autoreactive T and B cells to trigger immunological tolerance. We generated a new recombinant protein by connecting the extracellular domain of murine TIGIT to the Fc region of the rat immunoglobulin IgG2a. The fusion protein was then characterized. The results suggested that among mice with lupus that were treated with the TIGIT-Ig fusion protein, the onset of proteinuria was delayed, serum concentrations of autoantibodies, such as antinuclear antibodies, were reduced without a decrease in the total IgG concentrations, and the survival rate was significantly increased compared to those of the controls. In conclusion, TIGIT-Ig administration showed promising results for both the prevention and treatment of autoimmune diseases in mice. This indicates that treatment with recombinant human TIGIT-Ig shows promise as an effective way to treat human autoimmune diseases.

immunology↗