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Qiao, S.-W.

Publications and source records attributed to Qiao, S.-W..

5 recordsLinked to original sources

A fast and inexpensive plate-based NGS library preparation method for insect genomics

Entomological sampling and storage conditions often prioritise efficiency, practicality and conservation of morphological characteristics, and may therefore be suboptimal for DNA preservation. This practice can impact downstream molecular applications, such as the generation of high-throughput genomic libraries, which often requires substantial DNA input amounts. Here, we investigate a fast and economical Tn5 transposase tagmentation-based library preparation method optimised for 96-well plates and low yield DNA extracts from insect legs stored under different conditions. Using a standardised input of 6ng DNA, library preparation costs were significantly reduced through the 6-fold dilution of a commercially available tagmentation enzyme. Costs were further suppressed by direct post-amplification pooling, skipping quality assessment of individual libraries. We find that reduced DNA yields associated with ethanol-based storage do not impede overall sequencing success. Furthermore, we find that the efficiency of tagmentation-based library preparation can be improved by thorough post-amplification bead clean-up which selects against both short and large DNA fragments. By lowering data generation costs, broadening the scope of whole genome studies to include low yield DNA extracts and increasing throughput, we expect this protocol to be of significant value for a range of applications in the field of insect genomics.

genomics↗

Stereotyped B-cell responses are linked to IgG constant region polymorphisms in multiple sclerosis

Clonally related B cells infiltrate the brain, meninges and cerebrospinal fluid (CSF) of multiple sclerosis (MS) patients, but the mechanisms driving the B-cell response and shaping the immunoglobulin repertoires remain unclear. Here, we used single-cell full-length RNA-seq and B-cell receptor reconstruction to simultaneously assess the phenotypes, isotypes, constant region polymorphisms, and the paired heavy- and light-chain repertoires in intrathecal B-lineage cells. We detected extensive clonal connections between the memory B cell and antibody-secreting cell (ASC) compartments and observed clonally related cells of different isotypes, including IgM/IgG1, IgG1/IgA1, IgG1/IgG2, and IgM/IgA1. There was a strong dominance of the G1m1 allotype constant region polymorphisms in ASCs, but not in memory B cells. Tightly linked to the G1m1 allotype, we found a preferential pairing of the IGHV4 gene family with the {kappa} variable (IGKV)1 gene family. These results link IgG constant region polymorphisms to stereotyped B-cell responses in MS, indicating that the intrathecal B-cell response in these patients could be directed against structurally similar epitopes. The data also suggest that the dominance of the G1m1 allotype in ASCs may occur as a result of biased differentiation of intrathecal memory B cells.

immunology↗

Longevity, clonal relationship and transcriptional program of celiac disease-specific plasma cells

Disease-specific plasma cells (PCs) reactive with transglutaminase 2 (TG2) or deamidated gluten peptides (DGP) are abundant in celiac disease (CeD) gut lesions. Their contribution toward CeD pathogenesis is unclear. We assessed expression of markers associated with PC longevity in 15 untreated and 26 treated CeD patients in addition to 13 non-CeD controls, and performed RNA-sequencing with clonal inference and transcriptomic analysis of 3251 single PCs. We observed antigen-dependent V-gene selection and stereotypic antibodies. Generation of recombinant DGP-specific antibodies revealed a key role of a heavy-chain residue that displays polymorphism, suggesting that immunoglobulin gene polymorphisms may influence CeD-specific antibody responses. We identified transcriptional differences between CeD-specific vs non-disease-specific PCs and between short-lived vs long-lived PCs. The short-lived CD19+CD45+ phenotype dominated in untreated and short-term-treated CeD, in particular among disease-specific PCs but also in the general PC population. Thus, the disease lesion of untreated CeD is characterized by massive accumulation of short-lived PCs that are not only directed against disease-specific antigens.

immunology↗

Single cell transcriptome profiling of the Atlantic cod immune system

The Atlantic cods unusual immune system, entirely lacking the Major Histocompatibility class II pathway, has prompted intriguing questions about what mechanisms are used to combat bacterial infections and how immunological memory is generated. Here, we examine the diversity of 8,180 spleen cells and peripheral blood leukocytes by single cell RNA sequencing. Unbiased transcriptional clustering revealed eleven distinct immune cell signatures. Resolution at the single cell level enabled characterisation of the major cell subsets including the cytotoxic T cells, B cells, erythrocytes, thrombocytes, neutrophils and macrophages. Further, we describe for the first time rare cell subsets which may represent dendritic cells, natural killer-like cells and a population of cytotoxic cells expressing GATA-3. We propose putative gene markers for each cluster and describe the relative proportions of each cell type in the spleen and peripheral blood leukocytes. By single cell analysis, this study provides the most detailed molecular and cellular characterization of the immune system of the Atlantic cod so far.

immunology↗

Resident memory CD8 T cells persist for years in human small intestine

In human small intestine, most CD8 T cells in the lamina propria and epithelium express a resident memory (Trm) phenotype and persist for at least one year in transplanted tissue. Intestinal CD8 Trm cells have a clonally expanded immune repertoire that is stable over time and exhibit enhanced protective capabilities. Graphical abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=199 SRC="FIGDIR/small/553792v1_ufig1.gif" ALT="Figure 1"> View larger version (98K): org.highwire.dtl.DTLVardef@10c19aaorg.highwire.dtl.DTLVardef@168e86forg.highwire.dtl.DTLVardef@73f0f5org.highwire.dtl.DTLVardef@1d08d10_HPS_FORMAT_FIGEXP M_FIG C_FIG HighlightsO_LIThe vast majority of CD8 T cells in the human small intestine are Trm cells C_LIO_LICD8 Trm cells persist for >1 year in transplanted duodenum C_LIO_LIIntraepithelial and lamina propria CD8 Trm cells show highly similar TCR repertoire C_LIO_LIIntestinal CD8 Trm cells efficiently produce cytokines and cytotoxic mediators C_LI

immunology↗