Development of a Novel CD26-Targeted Chimeric Antigen Receptor T-Cell Therapy for CD26-Expressing T-Cell Malignancies.

Chimeric-antigen-receptor (CAR) T-cell therapy for CD19-expressing B-cell malignancies is already widely adopted in clinical practice. On the other hand, the development of CAR-T-cell therapy for T-cell malignancies is in its nascent stage. One of the potential targets is CD26, to which we have developed and evaluated the efficacy and safety of the humanized monoclonal antibody YS110. We generated second (CD28) and third (CD28/4-1BB) generation CD26-targeted CAR-T-cells (CD26-2G/3G) using YS110 as the single-chain variable fragment. When co-cultured with CD26-overexpressing target cells, CD26-2G/3G strongly expressed the activation marker CD69 and secreted IFNgamma. In vitro studies targeting the T-cell leukemia cell line HSB2 showed that CD26-2G/3G exhibited significant anti-leukemia effects with the secretion of granzymeB, TNFα, and IL-8, with 3G being superior to 2G. CD26-2G/3G was also highly effective against T-cell lymphoma cells derived from patients. In an in vivo mouse model in which a T-cell lymphoma cell line, KARPAS299, was transplanted subcutaneously, CD26-3G inhibited tumor growth, whereas 2G had no effect. Furthermore, in a systemic dissemination model in which HSB2 was administered intravenously, CD26-3G inhibited tumor growth more potently than 2G, resulting in greater survival benefit. The third-generation CD26-targeted CAR-T-cell therapy may be a promising treatment modality for T-cell malignancies.

DPP8 is a novel therapeutic target for multiple myeloma.

Dipeptidyl peptidases (DPPs) are proteolytic enzymes that are ideal therapeutic targets in human diseases. Indeed, DPP4 inhibitors are widely used in clinical practice as anti-diabetic agents. In this paper, we show that DPP4 inhibitors also induced cell death in multiple human myeloma cells. Among five DPP4 inhibitors, only two of them, vildagliptin and saxagliptin, exhibited apparent cytotoxic effects on myeloma cell lines, without any difference in suppression of DPP4 activity. As these two DPP4 inhibitors are known to have off-target effects against DPP8/9, we employed the specific DPP8/9 inhibitor 1G244. 1G244 demonstrated anti-myeloma effects on several cell lines and CD138+ cells from patients as well as in murine xenograft model. Through siRNA silencing approach, we further confirmed that DPP8 but not DPP9 is a key molecule in inducing cell death induced by DPP8/9 inhibition. In fact, the expression of DPP8 in CD38+ cells from myeloma patients was higher than that of healthy volunteers. DPP8/9 inhibition induced apoptosis, as evidenced by activated form of PARP, caspases-3 and was suppressed by the pan-caspase inhibitor Z-VAD-FMK. Taken together, these results indicate that DPP8 is a novel therapeutic target for myeloma treatment.

Electrical Control of Cyclotron Resonance in Dual-Gated Trilayer Graphene.

Landau levels (LLs) of ABA-stacked trilayer graphene (TLG) are described as the combination of monolayer graphene-like LLs and bilayer graphene-like LLs. They are extremely sensitive to the applied perpendicular electric displacement field D. Here, we demonstrate the electrical control of cyclotron resonance (CR) in a dual-gated ABA-stacked TLG. Under the irradiation of mid-infrared light, we observed the photovoltage induced by the CR absorption through the photothermoelectric effect. The resonant magnetic field in CR is changed by applying D while keeping the carrier density constant. Numerical simulations based on the tight-binding model complement the experimental observations. We believe that the present study provides a boost to graphene-based photodetectors and photoemitters with an electrically tunable wavelength in mid-infrared to terahertz spectral ranges.

Carbon-Rich Domain in Hexagonal Boron Nitride: Carrier Mobility Degradation and Anomalous Bending of the Landau Fan Diagram in Adjacent Graphene.

Hexagonal boron nitride (h-BN) crystals grown under ultrahigh pressures and ultrahigh temperatures exhibit a high crystallinity and are used throughout the world as ideal substrates and insulating layers in van der Waals heterostructures. However, in their central region, these crystals have domains which contain a significant density of carbon impurities. In this study, we utilized cathodoluminescence and far-ultraviolet photoluminescence to reveal that the carbon (C)-rich domain can exist even after exfoliation. Then, we studied the carrier transport of graphene in h-BN/graphene/h-BN van der Waals heterostructures, precisely arranging the graphene to straddle the border of the C-rich domain in h-BN. We found that the carrier mobility of graphene on the C-rich h-BN domain was significantly suppressed. In addition, characteristic bending of the Landau fan diagram was observed on the electron-doped side. These results suggest that the C-rich domain in h-BN forms an impurity level and induces extrinsic carrier scattering into adjacent graphene.

Possible Involvement of PI3-K/Akt-Dependent GSK-3ß Signaling in Proliferation of Neural Progenitor Cells After Hypoxic Exposure.

We previously demonstrated that proliferation of endogenous neural progenitor cells is enhanced by cerebral ischemia and that phosphatidylinositol 3-kinase (PI3-K)/Akt-dependent glycogen synthase kinase (GSK)-3ß signaling is involved in ischemia-induced neurogenesis. It is important to learn more about the regulation of proliferation and differentiation of neural progenitor cells under ischemic conditions, as such knowledge that may serve as the basis for the development of new therapeutic approaches for stroke. However, it remains to be addressed whether a change in that signaling pathway is induced in neural progenitor cells. We prepared neural progenitor cells by using the neurosphere method and conducted experiments to determine the relative contributions of the PI3-K/Akt-dependent GSK-3ß signaling pathway to the proliferation and differentiation of neural progenitor cells under the hypoxic condition in vitro. We showed that hypoxic exposure induced the proliferation of neural progenitor cells. This proliferation was accompanied by phosphorylation of Akt and GSK-3ß at its Ser9. Furthermore, treatment with a PI3-K inhibitor decreased the hypoxia-induced phosphorylation of GSK-3ß and proliferation of neural progenitor cells. Furthermore, hypoxic exposure enhanced the differentiation of neural progenitor cells, and this increased differentiation was not affected by treatment with the PI3-K inhibitor. Although the expression of NeuroD1 mRNA during cell differentiation was also enhanced by hypoxic exposure, this increased expression was not affected by treatment with the PI3-K inhibitor. Our findings suggest that the PI3K/Akt-dependent GSK-3ß signaling pathway was involved in the proliferation of neural progenitor cells under a pathologic condition, such as hypoxia and/or cerebral ischemia in vivo.

Involvement of GSK-3ß Phosphorylation Through PI3-K/Akt in Cerebral Ischemia-Induced Neurogenesis in Rats.

Glycogen synthase kinase (GSK)-3ß, which is abundantly expressed in the central nervous system, regulates various cellular processes including gene expression, cell proliferation, and differentiation. However, involvement of GSK-3ß in cerebral ischemia-induced endogenous neurogenesis is not yet fully understood. Appropriate strategies to prevent ischemic cell damage and subsequent severe sequelae are needed. The purpose of the present study was to determine the relationship between pathophysiological alteration of the GSK-3ß signaling pathway and cerebral ischemia-induced endogenous neurogenesis in rats. Severe cerebral ischemia was produced by the injection of 700 microspheres into the right internal carotid artery of rats. We demonstrated that phosphorylation of GSK-3ß at its Ser9 and that of Akt was significantly enhanced on day 7 after the cerebral ischemia, as was the number of NeuroD-positive cells. Treatment with a phosphatidylinositol 3-kinase (PI3-K) inhibitor decreased the cerebral ischemia-induced phosphorylation of Akt and that of GSK-3ß at its Ser9. In addition, as the protein levels of insulin-like growth factor-1 (IGF-1) and brain-derived neurotrophic factor (BDNF) were decreased, they might not have been essential for activation of the PI3-K/Akt/GSK-3ß pathway after severe cerebral ischemia. Although it remains to be determined what factors activate this pathway, our results suggest that PI3K/Akt-dependent GSK-3ß signaling and subsequent expression of NeuroD were involved in the neurogenesis elicited by cerebral ischemia.

Supercurrent in van der Waals Josephson junction.

Supercurrent flow between two superconductors with different order parameters, a phenomenon known as the Josephson effect, can be achieved by inserting a non-superconducting material between two superconductors to decouple their wavefunctions. These Josephson junctions have been employed in fields ranging from digital to quantum electronics, yet their functionality is limited by the interface quality and use of non-superconducting material. Here we show that by exfoliating a layered dichalcogenide (NbSe2) superconductor, the van der Waals (vdW) contact between the cleaved surfaces can instead be used to construct a Josephson junction. This is made possible by recent advances in vdW heterostructure technology, with an atomically flat vdW interface free of oxidation and inter-diffusion achieved by eliminating all heat treatment during junction preparation. Here we demonstrate that this artificially created vdW interface provides sufficient decoupling of the wavefunctions of the two NbSe2 crystals, with the vdW Josephson junction exhibiting a high supercurrent transparency.

Quantitative analysis of motifs contributing to the interaction between PLS-subfamily members and their target RNA sequences in plastid RNA editing.

In plant organelles, RNA editing alters specific cytidine residues to uridine in transcripts. Target cytidines are specifically recognized by pentatricopeptide repeat (PPR) proteins of the PLS subfamily, which have additional C-terminal E or E-DYW motifs. Recent in silico analysis proposed a model for site recognition by PLS-subfamily PPR proteins, with a correspondence of one PPR motif to one nucleotide, and with the C-terminal last S motif aligning with the nucleotide at position -4 with respect to the editing site. Here, we present quantitative biochemical data on site recognition by four PLS-subfamily proteins: CRR28 and OTP85 are DYW-class members, whereas CRR21 and OTP80 are E-class members. The minimal RNA segments required for high-affinity binding by these PPR proteins were experimentally determined. The results were generally consistent with the in silico-based model; however, we clarified that several PPR motifs, including the C-terminal L2 and S motifs of CRR21 and OTP80, are dispensable for the RNA binding, suggesting distinct contributions of each PPR motif to site recognition. We also demonstrate that the DYW motif interacts with the target C and its 5' proximal region (from -3 to 0), whereas the E motif is not involved in binding.

Boundary scattering in ballistic graphene.

We report magnetotransport measurements in ballistic graphene mesoscopic wires where the charge carrier mean free path is comparable to the wire width W. Magnetoresistance curves show characteristic peak structures where the peak field scales with the ratio of cyclotron radius R(c) and wire width W as W/R(c)=0.9±0.1, due to diffusive boundary scattering. The obtained proportionality constant between R(c) and W differs from that of a classical semiconductor two-dimensional electron system in which W/R(c)=0.55.

Autopsy case of delayed anaphylactic shock due to contrast medium.

We report an autopsy case of delayed anaphylactic shock due to contrast medium. A 17-year-old Japanese man underwent angiography using non-ionic contrast medium under the suspected diagnosis of Buerger's disease. Initial symptoms appeared 6 h after the administration of the contrast medium, and death was confirmed 11 h later. Considering the clinical course and the results of the autopsy, we concluded that the direct cause of the patient's death was severe acute circulatory failure due to a delayed allergic reaction to the contrast medium. The reported incidence of serious delayed reactions or biphasic reactions to non-ionic contrast medium is extremely low; however, we should be aware of such rare adverse reactions.

Atomic force microscopy based tunable local anodic oxidation of graphene.

We have fabricated graphene/graphene oxide/graphene (G/GO/G) junctions by local anodic oxidation lithography using atomic force microscopy (AFM). The conductance of the G/GO/G junction decreased with the bias voltage applied to the AFM cantilever V(tip). For G/GO/G junctions fabricated with large and small |V(tip)|. GO was semi-insulating and semiconducting, respectively. AFM-based LAO lithography can be used to locally oxidize graphene with various oxidation levels and achieve tunability from semiconducting to semi-insulating GO.

No need to fake it: reproduction of the Asch experiment without confederates.

In the present experiment, we replicated Asch's seminal study on social conformity without using confederates. We adapted a presentation trick in order to present two different stimuli secretly to groups of participants to create minorities and majorities without utilizing confederates. One hundred and four Japanese undergraduates (40 men and 64 women) carried out Asch-equivalent tasks in same-sex groups of four. In each group, we adapted the fMORI Technique to present the tasks such that one person (minority participant) observed different stimuli than the other three people (majority participants). The same nine stimulus sets that Asch had used were carefully reproduced as PowerPoint slides and projected onto a half-transparent screen. As for the critical tasks, the top part of the standard lines appeared in either green or magenta so that two groups of participants would see them differently when they wore two types of polarizing sunglasses that filtered either green or magenta to make the lines appear longer or shorter. A post-experimental questionnaire confirmed that no participant among either the minority or majority viewers noticed the presentation trick. The results showed that, in line with Asch's basic findings, the minority women participants conformed to the majority. However, our study produced two different results: While minority women conformed, minority men did not. Contrary to Asch's findings, the frequency of conformity of minority participants was almost the same regardless of whether the majority answered unanimously or not.

[Stapes surgery performed for congenital stapes foot plate fixation--comparison of prosthesis fixation to the malleus vs. the incus].

We report the surgical results of stapes surgery using the Schukneht-type wire piston prosthesis performed on 30 ears with fixation of the stapes footplate and absence of the long process of the incus. The prosthesis was reformed to avoid dislocation and fixed to the handle of the malleus. The surgical results in another 49 ears, the comparator group, in which the prosthesis was fixed to the long process of the incus because the anomaly was restricted to fixation of the footplate without other associated anomalies, were also analyzed for comparison. The mean postoperative air conduction hearing levels were 28.6dB in the subjects and 21.6dB in the comparator group, and the mean hearing improvements were 35.7dB and 29.7dB, respectively. The success rate of the operation, based on the criteria established by the Japan Otological Society, was 90% in the subjects and 98% in the comparator group. The mean postoperative air-bone gap in the subjects was 15.8dB, which was 4.3dB higher than that in the comparator group. The difference between the two groups was considered to be due to the difference in the effectiveness of the conduction mechanism after the surgery. We therefore concluded that the surgical procedure using the Schukneht-type wire piston prosthesis to fix the malleus handle is a useful surgical method that yields satisfactory results.

[Analysis of specific IgE antibodies to staphylococcal enterotoxins, total serum IgE and hemogramme in carriers of Staphylococcus aureus].

In order to evaluate the relationship between nasal carriers of S. aureus and their history of allergic diseases, the total serum IgE titer, the hemogramme pattern, and the titers of specific IgE antibody to Staphylococcal enterotoxins A and B (SEA and SEB) and of specific IgG antibody to SEB were investigated in 98 trade school students. Fifteen (15.3%) of the 98 students were sensitized to SEA and/or SEB (40.0% to SEA and 93.3% to SEB). In this group, 11 subjects were S. aureus carriers (73.0%) and 12 had a history of allergic diseases (80.0%). Low levels of specific IgG antibody to SEB were identified from both S. aureus carriers and non-carriers. The S. aureus carriers had significantly higher levels of total IgE titer than the non-carriers and the individuals with a history of allergic diseases had significantly higher total IgE titer levels than those having no history of allergic diseases (p < 0.01). In the hemogramme patterns of S. aureus carriers, a significant positive correlation was observed between the total IgE antibodies and the eosinophil rate (p < 0.05), and a negative correlation (p < 0.001) was recognized between the neutrophil and the lymphocyte rates.