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Tateno, H.

Publications and source records attributed to Tateno, H..

10 recordsLinked to original sources

In vivo effects of inducible transgene expression of the age-associated glycogenes St6gal1 and Man1a on epidermal homeostasis

Glycosylation of cell-surface proteins plays several essential roles in cell-matrix interactions and receptor signaling, thereby contributing to tissue homeostasis and aging. In aged mouse skin, epidermal stem cells exhibit increased levels of a2,6-sialylated complex-type N-glycans alongside upregulation of glycogenes such as St6gal1 and Man1a; however, the functional importance of these glycosylation changes in vivo remains largely unknown. Here, we generated doxycycline-inducible transgenic mice expressing the age-related glycogenes St6gal1 and Man1a, either individually or in combination, using ubiquitous and epidermis-specific drivers. Lectin-based analyses with SNA and rHeltuba demonstrated corresponding alterations in glycosylation patterns in these mice. Transgenic Man1a induction reduced epidermal proliferation and epidermal thickness. In contrast, St6gal1 induction caused splenomegaly and elevated expression of inflammatory signature genes in the skin but did not measurably alter epidermal proliferation or morphology. Double transgenic mice exhibited a hybrid phenotype combining inflammatory and proliferative impairments, although comparison of ubiquitous and epidermis-specific induction indicated that the observed skin phenotypes depended on the epidermal expression of the transgenes. An SNA lectin-based pull-down assay followed by mass spectrometry identified candidate a2,6-sialylated proteins, including integrin family members, junctional proteins, and surface receptors, following induction of St6gal1 and Man1a. Together, these findings suggest that increased expression of the age-associated glycogenes St6gal1 and Man1a perturbs distinct aspects of epidermal homeostasis in vivo and identify candidate glycoproteins that may mediate these effects.

cell biology↗

Senescence-associated loss of intestinal α1,2-fucose disrupts a modifiable host-microbiome homeostasis axis in people with HIV

BackgroundPeople with HIV (PWH), despite effective antiretroviral therapy (ART), experience disrupted intestinal homeostasis characterized by microbial dysbiosis and impaired intestinal barrier integrity, which contribute to chronic inflammation and aging-associated comorbidities. However, tractable mechanisms contributing to this dysfunction remain poorly defined. ObjectiveTo determine whether acquired loss of intestinal 1,2-fucose, a host-derived intrinsic prebiotic glycan that supports colonization by short-chain fatty acid (SCFA)-producing bacteria essential for intestinal barrier integrity, contributes to microbiome disruption, impaired epithelial resilience, inflammation, and biological aging in PWH. DesignIleal and colonic biopsies, isolated crypts, stool, and blood from PWH on ART and controls underwent multi-omic analyses. Findings were mechanistically interrogated using stool anaerobic fermentation assays and 3D intestinal organoid models of stress-mediated epithelial disruption. ResultsIn intestinal tissues, PWH exhibited reduced 1,2-fucosylation and increased senescence-associated expression of the fucose-degrading enzyme -L-fucosidase. Lower 1,2-fucose tracked with depletion of SCFA-producing bacteria, increased inflammation, and premature biological aging. In anaerobic fermentations, stool from PWH produced fewer SCFAs than controls, whereas supplementation with the human-milk-oligosaccharide-derived 1,2-fucose donor 2'-fucosyllactose restored SCFA production and improved intestinal organoid resilience to stress-mediated disruption. ConclusionThese findings identify acquired loss of intestinal 1,2-fucose as a modifiable host-microbiome mechanism linking epithelial senescence, microbial metabolic dysfunction, impaired barrier resilience, inflammation, and biological aging in treated HIV infection. SUMMARY BOXO_ST_ABSWhat is already known on this topicC_ST_ABSPeople with HIV on suppressive antiretroviral therapy frequently have persistent intestinal barrier dysfunction, microbial dysbiosis, chronic inflammation, and accelerated biological aging, but the host mechanisms that maintain this disrupted mucosal state remain incompletely defined. What this study addsThis study identifies acquired loss of intestinal 1,2-fucosylation as a feature of treated HIV infection and links this defect to a host fucosidase-high, senescence-enriched mucosal niche, depletion of SCFA-producing bacteria, impaired tight junction-associated barrier signatures, inflammation, and biological aging phenotypes. How this study might affect research, practice or policyThese findings support intestinal glycan ecology as a modifiable host-microbiome axis and provide a rationale for testing 1,2-fucose-replenishing strategies, such as 2'-fucosyllactose, to restore microbial metabolic output and improve epithelial resilience in people with HIV.

microbiology↗

Inhibiting Glycan Degradation Prevents HIV-Induced Inflammaging and Cognitive Impairment

Cognitive impairment is a frequent outcome of chronic viral infections linked to premature aging, including HIV. The mechanisms underlying this decline remain poorly understood. Here, we identify pro-inflammatory glycan degradation, characterized by loss of sialic acid and galactose, alterations that are hallmarks of premature aging, as key contributors to HIV-associated cognitive impairment (HIV-CI). In two independent cohorts of people living with HIV, these degradative changes were enriched in individuals with cognitive impairment, particularly females, and correlated with worse cognitive performance. In both a humanized mouse model of HIV and Eco-HIV, a complementary model that allows behavioral testing, pharmacological inhibition of glycan degradation with sialidase inhibitors prevented virally induced inflammation, immune activation, accelerated aging, and memory deficits. These findings implicate glycan degradation as a contributor to inflammation and cognitive impairment in HIV and highlight glycan-preserving therapies as a promising strategy to mitigate inflammation, premature aging, and cognitive decline during viral infections.

microbiology↗

Gut mucin fucosylation dictates the entry of botulinum toxin complexes

Botulinum toxins (BoNTs) are the most potent known bacterial toxins. The BoNT complex from Clostridium botulinum B-Okra (large progenitor toxin complex (L-PTC)/BOkra, hyper-oral-toxic) exerts at least 80-fold higher oral toxicity1 in mice compared with that from serotype A1 (L-PTC/A62A, non-hyper-oral-toxic). Here, we showed that L-PTC/BOkra was predominantly absorbed through enterocytes, whereas L-PTC/A62A targeted intestinal microfold cells. Furthermore, we demonstrated that 1,2-fucosylation of intestinal mucin determined the oral toxicity of L-PTCs as well as their entry routes; more specifically, these routes were governed by the carbohydrate-binding spectrum of hemagglutinin (HA) complex, which is one of the L-PTC components. Disruption of fucosylation in fucosyltrasferase-2 (Fut2)-null mice hindered the intestinal mucin penetration of L-PTC/BOkra via HA and reduced the susceptibility to its oral intoxication. Our data establish the molecular mechanism by which the oral toxicity of BoNTs is increased after they cross intestinal mucus layers.

microbiology↗

Targeting Siglec-10/α3β1 Integrin Interactions Enhances Macrophage-Mediated Phagocytosis of Pancreatic Cancer

Tumor-associated macrophages (TAMs) in the pancreatic ductal adenocarcinoma (PDAC) tumor microenvironment (TME) exhibit immunosuppressive phenotypes and impaired phagocytic activity, facilitating tumor progression and immune evasion. Here, we identify integrin 3{beta}1, composed of ITGA3 and ITGB1 subunits, as a sialylated glycoprotein ligand for Siglec-10, an inhibitory glyco-immune checkpoint receptor highly expressed on TAMs in PDAC. The interaction between Siglec-10 on TAMs and 3{beta}1 on PDAC cells suppresses macrophage-mediated phagocytosis, thereby promoting immune evasion. Consistently, disrupting Siglec-10 interactions with monoclonal antibodies significantly enhances macrophage phagocytosis of PDAC cells and alleviates myeloid cell-mediated inhibition of T cell proliferation and activation in vitro. In both a PDAC xenograft mouse model engrafted with human macrophages and a human Siglec-10 transgenic mouse model, targeting Siglec-10 with monoclonal antibodies reduces PDAC tumor growth. These findings suggest that Siglec-10 interactions are key mediators of TAM-driven immune evasion in PDAC and highlight the therapeutic potential of targeting these interactions to restore anti-tumor immunity. SIGNIFICANCEPancreatic tumor cells exploit integrin 3{beta}1 to engage the immunosuppressive checkpoint receptor Siglec-10 on myeloid cells, driving immune evasion, and antibody-mediated blockade of Siglec-10 restores myeloid cell-mediated anti-PDAC immunity.

immunology↗

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↗

Glyco-phenotyping of mutants of Lacticaseibacillus paracasei by lectin microarray

We previously identified a gene cluster of Lacticaseibacillus paracasei strain Shirota (YIT 9029) for cell surface long-chain polysaccharides (LCPS-1) biosynthesis, which modulates YIT 9029 activity to induce cytokine production in immune cells, and showed that a lectin microarray can be useful for distinguishing the profile of bacterial cell-surface polysaccharide (PS) structures. Therefore, we isolated disruptive mutant strains of 51 genes predicted to be involved in cell wall PS biosynthesis in YIT 9029. Their binding profiles to lectins in conjunction with their binding abilities to YIT 9029-specific monoclonal antibody (MAb) were compared. The mutants defective in binding to the MAb all had defects within the cps1 gene cluster. Some mutants partially bound to MAb, indicating that these genes may influence the synthesis and maturation of LCPS-1. Advanced lectin microarray analyzed the cell surface glycosylation properties of YIT 9029 and its mutants. YIT 9029 bound to a rhamnose-specific lectin CSA, and three additional lectins including an O-glycan binder (rDiscoidin II) and two mannose binders (rOrysata and rBanana). Lectin binding specificity was confirmed by a gene complementation assay for the cps1C gene and a carbohydrate inhibition assay. When the binding profiles of individual cps1A through cps1J knockout mutants were compared, typical and specific binding profiles patterns were observed, in which some similarities in the functions of each gene could be predicted. In conclusion, the combined use of lectin microarray and a YIT 9029 mutant strain library is a powerful tool for identifying unknown bacterial gene functions related to cell surface glycome. IMPORTANCEPreviously, only a limited number of methods have been available for studying mutations in bacterial cell surface polysaccharide structures in relation to gene function. In this study, we focused on the lectin-binding properties of Lacticaseibacillus paracasei YIT 9029 (wild-type; WT) and investigated the lectin-binding capabilities of 51 cell wall biosynthesis gene disruption strains using lectin microarrays. The results indicated that lectin-binding properties in gene-disrupted strains varied significantly with the presence or absence of LCPS-1, ranging from similar to WT to distinctly different. The use of lectin microarrays in conjunction with the YIT 9029 mutant library has been shown to be a highly effective method for identifying the functions of unknown bacterial genes related to cell-surface glycomes. This innovative approach to glycophenotyping allows for the determination of cell wall glycomes associated with bacterial gene functions using lectin microarrays.

microbiology↗

Production of offspring from azoospermic mice with meiotic failure: Precise biparental meiosis within halved oocytes

While the large volume of mammalian oocytes is necessary for embryo development, it can lead to error-prone chromosomal segregation during meiosis. Conversely, we hypothesized that smaller oocytes would have a great unidentified potential to stabilize unstable meiosis and improve the development of the resultant embryos. Here, we show that reducing ooplasmic volume can rescue highly error-prone fertilization using primary spermatocytes by preventing segregation errors of chromosomes during biparental meiosis. High-resolution live-imaging analysis revealed that erroneous chromosome segregation occurred in most (90%) spermatocyte-injected oocytes of normal size, but could be ameliorated to 40% in halved oocytes. The birth rate improved remarkably from 1% to 19% (P < 0.0001). Importantly, this technique enabled the production of offspring from azoospermic mice with spermatocyte arrest caused by STX2 deficiency, an azoospermia factor also found in humans. Thus, contrary to popular opinion, oocytes inherently have a strong potential for precise meiotic divisions, which can be evoked by reduction of the ooplasmic volume. Their potential might help rescue cases of untreatable human azoospermia with spermatocyte arrest.

developmental biology↗

Glycomic profiling of the gut microbiota by Glycan-seq

BackgroundThere has been immense interest in studying the relationship between the gut microbiota and human health. Bacterial glycans modulate the cross talk between the gut microbiota and its host. However, little is known about these glycans because of the lack of appropriate technology to study them. MethodsWe previously developed a sequencing-based glycan profiling method called Glycan-seq, which is based on the use of 39 DNA-barcoded lectins. In this study, we applied this technology to analyze the glycome of the intact gut microbiota of mice. Fecal microbiota was incubated with 39 DNA-barcoded lectins exposed to UV, and the number of released DNA barcodes were counted by next-generation sequencing to obtain a signal for each lectin bound to the microbiota. In parallel, the bacterial composition of the gut microbiota was analyzed by 16S rRNA gene sequencing. Finally, we performed a lectin pull-down experiment followed by 16S rRNA gene sequencing to identify lectin-reactive bacteria. ResultsThe evaluation of cultured gram-positive (Deinococcus radiodurans) and gram-negative (Escherichia coli) bacteria showed significantly distinct glycan profiles between these bacteria, which were selected and further analyzed by flow cytometry. The results of flow cytometry agreed well with those obtained by Glycan-seq, indicating that Glycan-seq can be used for bacterial glycomic analysis. We thus applied Glycan-seq to comparatively analyze the glycomes of young and old mice gut microbiotas. The glycomes of the young and old microbiotas had significantly distinct glycan profiles, which reflect the different bacterial compositions of young and old gut microbiotas based on 16S rRNA gene sequencing. Therefore, the difference in the glycomic profiles between young and old microbiotas may be due to their differing bacterial compositions. 2-6Sia-binders bound specifically to the young microbiota. Lectin pull-down followed by 16S rRNA gene sequencing of the young microbiota identified Lactobacillaceae as the most abundant bacterial family with glycans reacting with 2-6Sia-binders. ConclusionThe Glycan-seq system can, without any prior culturing and fluorescence labeling, reveal the glycomic profile of the intact bacterial gut microbiota. A combination of lectin pull-down and 16S rRNA gene sequencing can identify lectin-reactive bacteria.

microbiology↗

Integrated analysis of glycan and RNA in single cells

Single-cell sequencing has emerged as an indispensable technology to dissect cellular heterogeneity but never been applied to the simultaneous analysis of glycan and RNA. Using oligonucleotide-labeled lectins, we first established lectin-based glycan profiling of single cells by sequencing (scGlycan-seq). We then combined the scGlycan-seq with single-cell transcriptome profiling (scRNA-seq) for joint analysis of glycan and RNA in single cells (scGR-seq). Using scGR-seq, we analyzed the two modalities in human induced pluripotent stem cells (hiPSCs) before and after differentiation into neural progenitor cells at the single cell resolution. The combination of RNA and glycan separated the two cell types clearer than either one of them. Furthermore, integrative analysis of glycan and RNA modalities in single cells found known and novel lectins that were specific to hiPSCs and coordinated with neural differentiation. Taken together, we demonstrate that scGR-seq can reveal the cellular heterogeneity and biological roles of glycans across multicellular systems.

genomics↗