Micro-patterned culture of iPSC-derived alveolar and airway cells distinguishes SARS-CoV-2 variants.

iPS細胞から作った肺胞や気道の細胞によりSARS-CoV-2変異株の病原性を比較評価する. 京都大学プレスリリース. 2024-03-29.Micro-patterning a new system to induce alveolar and airway epithelial cells. 京都大学プレスリリース. 2024-03-29.The emergence of severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) variants necessitated a rapid evaluation system for their pathogenesis. Lung epithelial cells are their entry points; however, in addition to their limited source, the culture of human alveolar epithelial cells is especially complicated. Induced pluripotent stem cells (iPSCs) are an alternative source of human primary stem cells. Here, we report a model for distinguishing SARS-CoV-2 variants at high resolution, using separately induced iPSC-derived alveolar and airway cells in micro-patterned culture plates. The position-specific signals induced the apical-out alveolar type 2 and multiciliated airway cells at the periphery and center of the colonies, respectively. The infection studies in each lineage enabled profiling of the pathogenesis of SARS-CoV-2 variants: infection efficiency, tropism to alveolar and airway lineages, and their responses. These results indicate that this culture system is suitable for predicting the pathogenesis of emergent SARS-CoV-2 variants

Identification of an Anti–Integrin αvβ6 Autoantibody in Patients With Ulcerative Colitis

指定難病「潰瘍性大腸炎」の自己抗体発見 --新たな診断や治療開発へ--. 京都大学プレスリリース. 2021-03-09.Background and Aims: Ulcerative colitis is the most frequent type of inflammatory bowel disease and is characterized by colonic epithelial cell damage. Although involvement of autoimmunity has been suggested in ulcerative colitis, specific autoantigens/antibodies have yet to be elucidated. Methods: Using 23 recombinant integrin proteins, we performed enzyme-linked immunosorbent assays on sera from patients with ulcerative colitis and controls. Integrin expression and IgG binding in the colon tissues of patients with ulcerative colitis and controls were examined using immunofluorescence and coimmunoprecipitation, respectively. The blocking activity of autoantibodies was examined using solid-phase binding and cell adhesion assays. Results: Screening revealed that patients with ulcerative colitis had IgG antibodies against integrin αvβ6. In the training and validation groups, 103 of 112 (92.0%) patients with ulcerative colitis and only 8 of 155 (5.2%) controls had anti–integrin αvβ6 antibodies (P < .001), resulting in a sensitivity of 92.0% and a specificity of 94.8% for diagnosing ulcerative colitis. Anti–integrin αvβ6 antibody titers coincided with ulcerative colitis disease activity, and IgG1 was the major subclass. Patient IgG bound to the integrin αvβ6 expressed on colonic epithelial cells. Moreover, IgG of patients with ulcerative colitis blocked integrin αvβ6–fibronectin binding through an RGD (Arg-Gly-Asp) tripeptide motif and inhibited cell adhesion. Conclusions: A significant majority of patients with ulcerative colitis had autoantibodies against integrin αvβ6, which may serve as a potential diagnostic biomarker with high sensitivity and specificity

Usefulness of Preoperative High Systemic Immune-Inflammation Index as a Prognostic Biomarker in Patients Who Undergo Radical Cystectomy for Bladder Cancer: Multicenter Analysis

Evidence of the prognostic value of pretreatment systemic immune-inflammation index (SII) after radical cystectomy (RC) for bladder cancer is limited. This study aims to assess the association between preoperative SII and prognosis after RC for bladder cancer. In this multicenter retrospective study, we calculated preoperative SII as well as the neutrophil-lymphocyte ratio (NLR) and platelet-lymphocyte ratio (PLR) in 237 patients who underwent RC for bladder cancer between March 2009 and March 2018. Patients were classified into high SII and low SII groups by using the optimal cutoff value (438 &times; 109/L) based on receiver operating characteristic curve analysis for cancer-specific death. We compared cancer-specific survival (CSS) and overall survival (OS) between the two groups. To evaluate the prognostic impact of preoperative SII, we also performed Cox proportional regression analyses for CSS and OS. Of 237 patients, 127 patients were classified into the high SII group and 110 patients into the low SII group. During the follow-up period, 70 patients died of bladder cancer (30%) and 21 patients died from other causes (9%). Patients with high SII had significantly lower rates of CSS and OS than those with low SII (p &lt; 0.01 and p &lt; 0.01, respectively). Multivariable Cox proportional hazard analysis showed that high SII was independently associated with poor CSS (p = 0.01) and poor OS (p &lt; 0.01). In conclusion, high SII could be an independent significant predictor of poor prognosis after RC in patients with bladder cancer

Imaging of Cerebral Amyloid Angiopathy with Bivalent 99m Tc-Hydroxamamide Complexes

Cerebral amyloid angiopathy (CAA), characterized by the deposition of amyloid aggregates in the walls of cerebral vasculature, is a major factor in intracerebral hemorrhage and vascular cognitive impairment and is also associated closely with Alzheimer's disease (AD). We previously reported 99m Tc-hydroxamamide (99m Tc-Ham) complexes with a bivalent amyloid ligand showing high binding affinity for β-amyloid peptide (Aβ(1-42)) aggregates present frequently in the form in AD. In this article, we applied them to CAA-specific imaging probes, and evaluated their utility for CAA-specific imaging. In vitro inhibition assay using Aβ(1-40) aggregates deposited mainly in CAA and a brain uptake study were performed for 99m Tc-Ham complexes, and all 99m Tc-Ham complexes with an amyloid ligand showed binding affinity for Aβ(1-40) aggregates and very low brain uptake. In vitro autoradiography of human CAA brain sections and ex vivo autoradiography of Tg2576 mice were carried out for bivalent 99m Tc-Ham complexes ([ 99m Tc]SB2A and [ 99m Tc]BT2B), and they displayed excellent labeling of Aβ depositions in human CAA brain sections and high affinity and selectivity to CAA in transgenic mice. These results may offer new possibilities for the development of clinically useful CAA-specific imaging probes based on the 99m Tc-Ham complex

Development of novel 123I-labeled pyridyl benzofuran derivatives for SPECT imaging of β-amyloid plaques in Alzheimer's disease.

Imaging of β-amyloid (Aβ) plaques in the brain may facilitate the diagnosis of cerebral β-amyloidosis, risk prediction of Alzheimer's disease (AD), and effectiveness of anti-amyloid therapies. The purpose of this study was to evaluate novel (123)I-labeled pyridyl benzofuran derivatives as SPECT probes for Aβ imaging. The formation of a pyridyl benzofuran backbone was accomplished by Suzuki coupling. [(123)I/(125)I]-labeled pyridyl benzofuran derivatives were readily prepared by an iododestannylation reaction. In vitro Aβ binding assays were carried out using Aβ(1-42) aggregates and postmortem human brain sections. Biodistribution experiments were conducted in normal mice at 2, 10, 30, and 60 min postinjection. Aβ labeling in vivo was evaluated by small-animal SPECT/CT in Tg2576 transgenic mice injected with [(123)I]8. Ex vivo autoradiography of the brain sections was performed after SPECT/CT. Iodinated pyridyl benzofuran derivatives showed excellent affinity for Aβ(1-42) aggregates (2.4 to 10.3 nM) and intensely labeled Aβ plaques in autoradiographs of postmortem AD brain sections. In biodistribution experiments using normal mice, all these derivatives displayed high initial uptake (4.03-5.49% ID/g at 10 min). [(125)I]8 displayed the quickest clearance from the brain (1.30% ID/g at 60 min). SPECT/CT with [(123)I]8 revealed higher uptake of radioactivity in the Tg2576 mouse brain than the wild-type mouse brain. Ex vivo autoradiography showed in vivo binding of [(123)I]8 to Aβ plaques in the Tg2576 mouse brain. These combined results warrant further investigation of [(123)I]8 as a SPECT imaging agent for visualizing Aβ plaques in the AD brain

Enhancement of Binding Affinity for Amyloid Aggregates by Multivalent Interactions of ^99mTc-Hydroxamamide Complexes

Deposition of amyloid aggregates has been regarded as an early stage of amyloidosis progression. An imaging probe that can image amyloid aggregates enables the early diagnosis of amyloidosis and contributes to the development of new medical therapies. High binding affinity for amyloid aggregates is essential to develop a useful molecular imaging probe. This article describes a new strategy to enhance the binding affinity of imaging agents targeting amyloid aggregates. We designed and synthesized novel ^99mTc-hydroxamamide (^99mTc-Ham) complexes with a bivalent amyloid ligand and evaluated their binding affinity for amyloid aggregates by using β-amyloid peptide (Aβ(1–42)) aggregates as a model. In vitro inhibition assay indicated that bivalent ^99mTc-Ham complexes had much higher binding affinity for amyloid aggregates than monovalent complexes. In vitro autoradiography using <i>Tg2576</i> mice showed the specific binding of bivalent ^99mTc-Ham complexes to Aβ plaques in the mouse brain, as reflected in the results of the inhibition assay. The preliminary results suggest that a new molecular design based on bivalent ^99mTc-Ham complexes may be reasonable to develop an imaging probe targeting amyloid aggregates

AC Impedance Analysis of the Degeneration and Recovery of Argyrodite Sulfide-Based Solid Electrolytes under Dry-Room-Simulated Condition

Toward the development of all-solid-state batteries with enhanced performance, this study describes the investigation of the degeneration mechanism under low-humid conditions of an argyrodite-type sulfide-based solid electrolyte. The degeneration of the electrolyte with moisture occurs even under the condition of super-low humidity in a dry room with a dew point (dp) as low as −50 °Cdp. Formation of hydrogen sulfide is detected when the electrolyte is exposed to dry air with −20 °Cdp. The results of impedance measurements suggest that the grain surface of the electrolyte is degenerated with moisture, resulting in a decrease in the lithium-ion conductivity at the grain boundary. The degenerated electrolyte surface can be partially recovered by heating at 170 °C in vacuo, although a small degeneration in bulk may occur in the heating process

Structure–Activity Relationship Study of Heterocyclic Phenylethenyl and Pyridinylethenyl Derivatives as Tau-Imaging Agents That Selectively Detect Neurofibrillary Tangles in Alzheimer’s Disease Brains

In order to explore novel tau-imaging agents that can selectively detect neurofibrillary tangles in Alzheimer’s disease (AD) brains, we designed and synthesized a series of heterocyclic phenylethenyl and (3-pyridinyl)­ethenyl derivatives with or without a dimethyl amino group. In <i>in vitro</i> autoradiography using AD brain sections, all radioiodinated ligands with a dimethyl amino group bound to Aβ deposits in the sections. In contrast, the ligands without a dimethyl amino group showed different patterns of radioactivity accumulation in the sections depending on the kind of heterocycle contained in their molecules. Particularly, a phenylethenyl benzimidazole derivative ([¹²⁵I]<b>64</b>) showed marked radioactivity accumulation in the temporal lobe which corresponded with the distribution of tau deposits. [¹²⁵I]<b>64</b> also showed the most favorable pharmacokinetics in normal mouse brains (3.69 and 0.06% ID/g at 2 and 60 min postinjection, respectively) among all ligands in this study. Taken together, these results suggest that [¹²³I]<b>64</b> may be a new candidate tau-imaging agent