Differential expression of CD45RO (UCHL1) and its functional relevance in two subpopulations of circulating TCR-γ/δ+ lymphocytes

金沢大学大学院医学系研究科血管病態制御学We examined the developmental profile of TCR-γ/δ+ cells with respect to CD45RO expression. Although total TCR-γ/δ+ cells were negligible in the neonatal blood and increased with advancing age, most blood TCR-γ/δ+ cells markedly expressed CD45RO without a distinction of age, probably reflecting a different CD45RO expression of two subsets defined by BB3 and δTCS1 mAbs. The vast majority of BB3+ cells expressed CD45RO, whereas expression of CD45RO was virtually absent in the δTCS1+ population. Functional studies revealed that, while both TCR-γ/δ+ cell subsets showed CD3-mediated activation, only BB3+ (or TiγA+) cells, but not δTCS1+ cells, appeared to proliferate in response to PPD in PPD-reactive individuals. The results suggested that the CD45RO+ (BB3+ or TiγA+) subset among blood TCR-γ/δ+ cells may be mainly involved in the memory or primed component of the immune system responding to some foreign antigens

Role of interleukin 6 for differential responsiveness of naive and memory CD4+ T cells in CD2-mediated activation

金沢大学大学院医学系研究科血管病態制御学The present study was undertaken to elucidate different requirements for CD2-mediated activation of naive (CD45RO-) and memory (CD45RO+) CD4+ T cells. A mitogenic combination of anti-CD2 (anti-T112 and anti-T113) mAbs could effectively induce the proliferation of memory CD4+ T cells even in the absence of monocytes. In marked contrast, naive CD4+ T cells did not disclose any proliferative responses to antiCD2 mAbs, when monocytes were absent in culture. This differential responsiveness of naive and memory CD4+ T cells appeared to be related largely to a difference in IL-6 - producing ability between both populations. IL-6 among monocyte-derived cytokines could correct unresponsiveness of naive CD4+ T cells to anti-CD2 stimulation. Unlike naive CD4+ T cells, memory CD4+ T cells produced IL-6 by themselves, with its mRNA being expressed on anti-CD2 stimulation. Anti-IL-6R mAb significantly inhibited proliferation of memory CD4+ T cells seen in the anti-CD2-stimulated cultures without monocytes, indicating the involvement of their own production of IL-6 in CD2-mediated activation. The results suggest an essential role of IL-6 for triggering of CD4+ T cells via the CD2 molecule

Role of interleukin 6 for differential responsiveness of naive and memory CD4+ T cells in CD2-mediated activation

The present study was undertaken to elucidate different requirements for CD2-mediated activation of naive (CD45RO-) and memory (CD45RO+) CD4+ T cells. A mitogenic combination of anti-CD2 (anti-T112 and anti-T113) mAbs could effectively induce the proliferation of memory CD4+ T cells even in the absence of monocytes. In marked contrast, naive CD4+ T cells did not disclose any proliferative responses to antiCD2 mAbs, when monocytes were absent in culture. This differential responsiveness of naive and memory CD4+ T cells appeared to be related largely to a difference in IL-6 - producing ability between both populations. IL-6 among monocyte-derived cytokines could correct unresponsiveness of naive CD4+ T cells to anti-CD2 stimulation. Unlike naive CD4+ T cells, memory CD4+ T cells produced IL-6 by themselves, with its mRNA being expressed on anti-CD2 stimulation. Anti-IL-6R mAb significantly inhibited proliferation of memory CD4+ T cells seen in the anti-CD2-stimulated cultures without monocytes, indicating the involvement of their own production of IL-6 in CD2-mediated activation. The results suggest an essential role of IL-6 for triggering of CD4+ T cells via the CD2 molecule

ATF6α/β-mediated adjustment of ER chaperone levels is essential for development of the notochord in medaka fish.

ATF6α and ATF6β are membrane-bound transcription factors activated by regulated intramembrane proteolysis in response to endoplasmic reticulum (ER) stress to induce various ER quality control proteins. ATF6α- and ATF6β single-knockout mice develop normally, but ATF6α/β double knockout causes embryonic lethality, the reason for which is unknown. Here we show in medaka fish that ATF6α is primarily responsible for transcriptional induction of the major ER chaperone BiP and that ATF6α/β double knockout, but not ATF6α- or ATF6β single knockout, causes embryonic lethality, as in mice. Analyses of ER stress reporters reveal that ER stress occurs physiologically during medaka early embryonic development, particularly in the brain, otic vesicle, and notochord, resulting in ATF6α- and ATF6β-mediated induction of BiP, and that knockdown of the α1 chain of type VIII collagen reduces such ER stress. The absence of transcriptional induction of several ER chaperones in ATF6α/β double knockout causes more profound ER stress and impaired notochord development, which is partially rescued by overexpression of BiP. Thus ATF6α/β-mediated adjustment of chaperone levels to increased demands in the ER is essential for development of the notochord, which synthesizes and secretes large amounts of extracellular matrix proteins to serve as the body axis before formation of the vertebra

Generation of medaka gene knockout models by target-selected mutagenesis

We have established a reverse genetics approach for the routine generation of medaka (Oryzias latipes) gene knockouts. A cryopreserved library of N-ethyl-N-nitrosourea (ENU) mutagenized fish was screened by high-throughput resequencing for induced point mutations. Nonsense and splice site mutations were retrieved for the Blm, Sirt1, Parkin and p53 genes and functional characterization of p53 mutants indicated a complete knockout of p53 function. The current cryopreserved resource is expected to contain knockouts for most medaka genes

The PI3K-Akt Pathway in SN-38-Induced Apoptosis in Human Gastric Cancer Cell Lines

SN-38, an active metabolite of a topoisomerase I inhibitor, CPT-11, exhibits a cytotoxic effect by inducing apoptosis in cancer cells. Phosphatidylinositol-3-OH kinase (PI3K)-Akt signaling is known to protect a variety of cells from apoptosis. The relationship between resistance to SN-38-induced apoptosis and the PI3K-Akt pathway in human gastric cancer cells is unknown. Here, we did an investigation using two gastric cancer cell lines, MKN1 and MKN45. Cell viability was determined by sodium 3'-[1-(phenylaminocarbonyl)-3,4-tetrazolium]-bis(4-methoxy-6-nitro) benzene sulfonic acid hydrate (XTT) assay. Apoptosis was confirmed by fluorescence microscopy using Hoechst 33342 staining. Expression levels of phospho-Akt (pAkt) were determined by Western blotting. After being treated with SN-38, the populations of sub-G1 cells were induced by flow cytometry in 36.8% of MKN45 cells more frequently than in 13.5% of MKN1 cells. SN-38 inhibited the expression of pAkt dose-dependently in MKN45 cells, but not in MKN1 cells. In MKN1 cells, an additional pretreatment with the PI3K inhibitor, LY294002, led to the inhibition of pAkt expression and induced apoptosis. The results suggested that SN-38 induces apoptosis by decreasing PI3K-Akt survival signaling, the anti-apoptotic signals, in human gastric cancer cells. Akt inhibitor might be a useful anti-tumor agent in combination with CPT-11

P-NETG2に対しPRRTを施行した4例に関する検討

In June 2021, 177Lu-oxodotreotide, a PRRT, was approved by insurance for unresectable or recurrent NETs. We investigated the efficacy and safety of PRRT in four patients with P-NETs at our hospital. All patients were confirmed to be positive for somatostatin receptors by using octreoscan. PRRT treatment was then performed and retrospectively evaluated for efficacy and safety. PRRT was administered as lutetium oxodotreotide（177Lu） at 7.4 GBq per dose over 30 - minutes for up to 1 - 4 doses at 8 - week intervals. Efficacy was evaluated using RECIST v1. 1. Adverse effects were evaluated by CTCAE（v5.0 JCOG）. The mean patient age was 60±12.0 years, and all patients were male. Three patients had a PS of 0, and one patient had a PS of 1 or higher. Metastatic organs were the liver in four patients and intra-abdominal lymph nodes in one patient, all of whom were Stage IV. Three patients underwent transarterial embolization. 177Lu-DOTATOC PRRT was administered every 8 weeks, and a total of four courses were administered in two patients, three courses in one patient, and one course in one patient. One patient had grade 2 thrombocytopenia after one course, and the second course was administered at a half dose（3.7 GBq）. The overall response rate（ORR） was 25%, with one PR and two SD. The median PFS was 9 months（95% Cl, 8-NA）, and the median overall survival from diagnosis was 119 months（95%Cl, 31 - NA）. Adverse events during PRRT included leukopenia in two patients（one G3, one G2）, lymphopenia in one patient（one G3）, thrombocytopenia in two patients（two G2, one G3）, creatinine increase in one patient（one G2）, and skin rash in one patient. In conclusion, PRRT is expected to be highly effective and safe compared with conventional therapy for neuroendocrine tumors with unresectable or distant metastases

合併症を有するB型大動脈解離に対するステントグラフト内挿術における腎動脈に対する治療戦略 : 多施設共同研究

Background: Management of abdominal branches associated with Stanford type B aortic dissection is controversial without definite criteria for therapy after thoracic endovascular aortic repair (TEVAR). This is in part due to lack of data on natural history related to branch vessels and their relationship with the dissection flap, true lumen, and false lumen. Purpose: To investigate the natural history of abdominal branches after TEVAR for type B aortic dissection and the relationship between renal artery anatomy and renal volume as a surrogate measure of perfusion. Materials and Methods: This study included patients who underwent TEVAR for complicated type B dissection from January 2012 to March 2017 at 20 centers. Abdominal aortic branches were classified with following features: patency, branch vessel origin, and presence of extension of the aortic dissection into a branch (pattern 1, supplied by the true lumen without branch dissection; pattern 2, supplied by the true lumen with branch dissection, etc). The branch artery patterns before TEVAR were compared with those of the last follow-up CT (mean interval, 19.7 months) for spontaneous healing. Patients with one kidney supplied by pattern 1 and the other kidney by a different pattern were identified, and kidney volumes over the course were compared by using a simple linear regression model. Results: Two hundred nine patients (mean age ± standard deviation, 66 years ± 13; 165 men and 44 women; median follow-up, 18 months) were included. Four hundred fifty-nine abdominal branches at the last follow-up were evaluable. Spontaneous healing of the dissected branch occurred in 63% (64 of 102) of pattern 2 branches. Regarding the other patterns, 6.5% (six of 93) of branches achieved spontaneous healing. In 79 patients, renal volumes decreased in kidneys with pattern 2 branches with more than 50% stenosis and branches supplied by the aortic false lumen (patterns 3 and 4) compared with contralateral kidneys supplied by pattern 1 (pattern 2 vs pattern 1: −16% ± 16 vs 0.10% ± 11, P = .002; patterns 3 and 4 vs pattern 1: −13% ± 14 vs 8.5% ± 14, P = .004). Conclusion: Spontaneous healing occurs more frequently in dissected branches arising from the true lumen than in other branch patterns. Renal artery branches supplied by the aortic false lumen or a persistently dissected artery with greater than 50% stenosis are associated with significantly greater kidney volume loss.博士（医学）・乙第1461号・令和2年6月30日Copyright © 2019 by authors and RSNA. This work is licensed under the Creative Commons Attribution International License (CC BY-NC-ND 4.0). https://creativecommons.org/licenses/by-nc-nd/4.0/