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Biology subjects

Kinoshita, H.

Publications and source records attributed to Kinoshita, H..

4 recordsLinked to original sources

Muc6-expressing gastric isthmus progenitors contribute to regeneration and metaplasia supported by myeloid-mesenchymal interactions

Gastric mucosal homeostasis is maintained by tissue-resident stem and progenitor cells residing in the isthmus region. Following mucosal injury, surviving cells contribute to regeneration, coinciding with characteristic pathological changes such as atrophic gastritis and metaplasia. To comprehensively understand the cellular dynamics involved in this process, we performed single-cell and spatial transcriptomics using newly generated transgenic mice. In human samples and mouse models, loss of gastric chief cells precedes, and even induces, loss of parietal cells during the progression of atrophy and metaplasia, validating the causal relationship underlying the decrease of these two lineages. Single-cell analysis confirmed robust stemness and metaplastic changes in the Muc6-expressing neck lineage following either chief or parietal cell ablation, and lineage-tracing experiments revealed that Muc6-expressing isthmus progenitors serve as a source of metaplasia and regeneration. Mechanistically, mucosal injury recruits IL-1-expressing myeloid cells, which stimulates NRG1 production in stromal fibroblasts, leading to mucosal proliferation and regeneration mediated by Myc activation in isthmus progenitors. These findings highlight the injury-responsible stem cell-like function of Muc6-expressing isthmal progenitors, which play a critical role in mucosal homeostasis and disease progression. Visual abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=109 SRC="FIGDIR/small/648856v1_ufig1.gif" ALT="Figure 1"> View larger version (27K): org.highwire.dtl.DTLVardef@10fc2eaorg.highwire.dtl.DTLVardef@1c5b82corg.highwire.dtl.DTLVardef@1be747dorg.highwire.dtl.DTLVardef@d1d722_HPS_FORMAT_FIGEXP M_FIG C_FIG

cell biology↗

Genome-wide mapping of the Galleria mellonella larvae transcription start sites during fungal infection and treatment

Using Low Quantity single strand CAGE (LQ-ssCAGE), we mapped the transcription start sites (TSS). We annotated the 5 end of the invertebrate Galleria mellonella, an upcoming and booming experimental model in infectious disease and immunology research. However, the current genome annotation of this model organism lacks annotation of the 5 end and TSS information. G. mellonella larva was infected with the fungal pathogen Madurella mycetomatis to map TSS under healthy and infection conditions. Larvae were first treated with itraconazole or ravuconazole, and then RNA-seq and LQ-ssCAGE libraries were prepared and sequenced 4, 30, and 52 hours following infection. The LQ-ssCAGE data was processed to identify CAGE transcription start site (CTSS), uni-, and bi-directional clusters. LQ-ssCAGE enabled us to precisely identify 39,410 TSS and 249 active enhancers; we assigned genomic features to the resulting TSSs and enhancers. The majority of the TSS peaks are annotated as promoter regions, while the enhancers were annotated as intergenic and genic. Furthermore, we confirmed the quality of TSS calling by promoter shapes and GC bias. Furthermore, we identified a set of super-enhancers and predicted de-novo motifs. The raw and processed data was deposited to NCBI GEO GSE282923. CTSS, TSS peaks, and enhancers coordinated are available through the ZENBU Genome browser. In this study, we reported the first atlas of TSS and active enhancers of G. mellonella.

genomics↗

Different efficacies of neutralizing antibodies and antiviral drugs on SARS-CoV-2 Omicron subvariants, BA.1 and BA.2

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Omicron subvariant BA.2 has spread in many countries, replacing the earlier Omicron subvariant BA.1 and other variants. Here, using a cell culture infection assay, we quantified the intrinsic sensitivity of BA.2 and BA.1 compared with other variants of concern, Alpha, Gamma, and Delta, to five approved-neutralizing antibodies and antiviral drugs. Our assay revealed the diverse sensitivities of these variants to antibodies, including the loss of response of both BA.1 and BA.2 to casirivimab and of BA.1 to imdevimab. In contrast, EIDD-1931 and nirmatrelvir showed a more conserved activities to these variants. The viral response profile combined with mathematical analysis estimated differences in antiviral effects among variants in the clinical concentrations. These analyses provide essential evidence that gives insight into variant emergences impact on choosing optimal drug treatment.

microbiology↗

Development of a microfluidic cell culture and monitoring system for intracellular signaling studies

We describe a microfluidic cell culture and monitoring system that temporally controls molecule concentrations around cells cultured in a small space. The simple system consists of three syringe pumps and a microfluidic device with two inlet ports and two outlet ports. Each syringe pump discharges or draws culture medium, solutions containing signal molecules, or cell suspensions through a port in a programmed flow rate sequence. Signal molecule solutions of differing concentration are merged in a microchannel, mixed immediately, and transported into the cell culture chamber. Regulating the flow rate ratio of syringe pumps over time enables dynamic control of the concentration of signal molecules in the cell culture chamber. The system provides various time-dependent waveforms of concentration over cultured cells, including pulse, rectangular, and triangular. The practical performance of the system for concentration control was evaluated using fluorescent dye imaging. The system was also used with CHO-K1 cells to measure intracellular Ca2+ concentrations, which vary with extracellular ATP levels. When a rectangular pulse of ATP was applied to the cells, Ca2+ levels increased quickly. By contrast, several Ca2+ peaks were observed in response to stepwise increases in ATP concentration. Single-cell Ca2+ responses to ATP pulse stimulation were analyzed by quantitative fluorescence imaging. Hierarchical clustering and quantitative analysis of single-cell data revealed the diversity of Ca2+ responses to ATP pulse stimulation. These results demonstrate that the microfluidic cell culture system is useful for studying a variety of cellular responses, including cell signaling.

bioengineering↗