伊藤 弘康

Obesity and high-fat diet (HFD) are known to cause proinflammatory and procoagulation states and suggested to become a risk of developing thromboembolic diseases. Non-alcoholic fatty liver disease (NAFLD) is usually associated with obesity and HFD, and a part of NAFLD is known to progress to nonalcoholic steatohepatitis (NASH), the pathogenesis of which has not been fully elucidated. In the current study, we examined the influence of short-term HFD on hepatic expression of the molecules related to inflammation, coagulation, metabolism, and cellular stresses from the perspective that HFD itself can be a risk for the development to NASH. In the analysis in short-term (4 days to 14 days) HFD-fed mice, we found out that HFD increased hepatic expression of IFN-γ, TNF-α, IL-10, monocyte chemotactic protein-1 (MCP-1), tissue factor (TF), plasminogen activator inhibitor-1 (PAI-1) mRNAs, and fibrin/fibrinogen deposition in the liver tissues. And it was suggested that metabolic alterations and endoplasmic reticulum (ER) stresses induced by the HFD intake were associated with this proinflammatory and procoagulation states. When we administered concanavalin A (Con A) to these HFD-fed mice, the extent of liver injury was dramatically exacerbated in HFD-fed mice. Heparin treatment to Con A-administered, HFD-fed mice (for 4 days) profoundly ameliorated the extent of liver injury. These suggest that even short-term of HFD intake induces proinflammatory and procoagulation states in the liver and thereby increases the susceptibility of the liver to circulating inflammatory stimuli. We think that it may explain a part of NASH pathogenesis.

扁平上皮癌関連(SCC)抗原は子宮頸癌、各組織の扁平上皮癌で陽性化し、治療のモニタリングマーカーとして利用されている。本研究において、われわれは新規SCC抗原測定試薬の基礎的検討を行った。測定にはルミパルスL2400を用い、通常測定法(反応時間20分)と短時間測定法(反応時間14分)の両測定法の検討を実施した。検出限界および定量限界については通常測定法において短時間測定法よりも優れる結果となったが、いずれも良好な成績であった。その他、併行精度ならびに室内精度、選択性、直線性、添加回収試験、対照法との比較試験についても良好な結果を得た。本SCC抗原測定試薬は、通常測定法、短時間測定法のいずれにおいても良好な基本性能を有していることが確認された。本試薬によるSCC抗原の院内測定は、良好な試薬性能および迅速な測定から日常検査に有用であり、疾患モニタリングとしての診療への貢献も期待できる。(著者抄録)

A persistent hepatitis B virus (HBV) infection is characterized by a lack of or a weak immune response to HBV. Efficient induction of the HBV-specific immune response leads to the clearance of HBV. Stimulator of interferon (IFN) genes (STING) is a cytoplasmic sensor of intracellular DNA from microbes and host cells. In the present study, we examined the efficacy of cyclic guanosine monophosphate-adenosine monophosphate (cGAMP) that is a ligand of the STING pathway as an HBV vaccine adjuvant. Wild-type (WT) mice and HBV-transgenic (HBV-Tg) mice were immunized with hepatitis B surface antigen (HBsAg) and cGAMP. The vaccination with HBsAg and cGAMP significantly enhanced the humoral and cellular immune response to HBsAg in WT and HBV-Tg mice. Cytokine production related to Th1 and Th2 responses and the activation of antigen-presenting cells in lymphoid tissues were induced by cGAMP. Vaccination using cGAMP may overcome tolerance in patients with chronic HBV infection.

全自動血液凝固測定装置のCSシリーズにおいて血小板凝集能の測定機能が搭載され、これまで検査者による分注が必要であった工程が自動で行われるようにまった。また、2濃度法をベースにした解析法であるPlatelet Aggregation Level(PAL)が新たに開発され、ADPを試薬として検査したときには「ADP induced PAL」と結果が算出され、コラーゲンを試薬としたときには「Collagen induced PAL」と結果が算出されるようになった。今回、CSシリーズに新たに搭載されたPALと、既存のヘマトレーサーシリーズに搭載されている解析法(Natural Standard Range)について比較検討を行い、PALの有用性が確認されたので報告した。

可溶性インターロイキン-2レセプター(sIL-2R)は悪性リンパ腫をはじめとする種々の疾患の病態モニタリングマーカーとして利用されている。本研究において、われわれはsIL-2R測定試薬「ルミパルスプレストIL-2R」の基礎的検討を行った。測定にはルミパルスL2400を用い、通常時間測定法(反応時間20分)と短時間測定法(反応時間14分)の両測定法の検討を実施した。併行精度、室内精度、検出限界および定量限界については通常時間測定法において短時間測定法よりも優れる結果となったが、いずれも良好な成績であった。その他、選択性、希釈直線性、添加回収、対照法との比較についても良好な結果を得た。ルミパルスプレストIL-2Rは、通常時間測定法、短時間測定法のいずれにおいても良好な基本性能を有していることが確認された。本試薬によるsIL-2Rの院内測定は、良好な試薬性能および迅速な測定から日常検査に有用であり、診察前検査としての診療への貢献も期待できる。(著者抄録)

心エコーによって計測されるTAPSE(三尖弁輪収縮移動距離)は、MRIで計測された右室収縮率と強い相関を示す。また、心エコーによって計測される右室内腔面積変化率(RVFAC)も、MRIで計測された右室収縮率と強い相関を示し、TAPSEよりも相関性の高い指標とされている。今回、心胸部外科手術がTAPSEとRVFACに及ぼす影響について検討した。対象は、当院で2012〜2016年に初回心胸部外科手術を行った56例(冠動脈バイパス術16例、大動脈弁置換術40例)とした。検討の結果、冠動脈バイパス術施行群・大動脈弁置換術群ともTAPSEは術後1ヵ月時に著明な低下を認め、その後緩やかな改善が認められた。RVFACは両群とも有意な変化は認められなかった。TAPSEの低下は、右心機能不全による影響よりも、右室の器質的変化による影響を強く受けていると考えられた。

Indoleamine 2,3-dioxygenase (IDO), a tryptophan-catabolizing intracellular enzyme of the L-kynurenine pathway, causes preneoplastic cells and tumor cells to escape the immune system by inducing immune tolerance; this mechanism might be associated with the development and progression of human malignancies. In the present study, we investigated the role of IDO in diethylnitrosamine (DEN)-induced hepatocarcinogenesis by using IDO-knockout (KO) mice. To induce hepatocellular carcinoma (HCC), hepatic adenoma, and preneoplastic hepatocellular lesions termed foci of cellular alteration (FCA), male IDO-wild-type (WT) and IDO-KO mice with a C57BL/6J background received a single intraperitoneal injection of DEN at 2 weeks of age. The mice were sacrificed to evaluate the development of FCA and hepatocellular neoplasms. HCC overexpressed IDO and L-kynurenine compared to surrounding normal tissue in the DEN-treated IDO-WT mice. The number and cell proliferative activity of FCAs, and the incidence and multiplicity of HCC were significantly greater in the IDO-WT than in the IDO-KO mice. The expression levels of the IDO protein, of L-kynurenine, and of IFN-gamma, COX-2, TNF-alpha, and Foxp3 mRNA were also significantly increased in the DEN-induced hepatic tumors that developed in the IDO-WT mice. The mRNA expression levels of CD8, perforin and granzyme B were markedly increased in hepatic tumors developed in IDO-KO mice. Moreover, Foxp3-positive inflammatory cells had infiltrated into the livers of DEN-treated IDO-WT mice, whereas fewer cells had infiltrated into the livers of IDO-KO mice. Induction of IDO and elevation of L-kynurenine might play a critical role in both the early and late phase of liver carcinogenesis. Our findings suggest that inhibition of IDO might offer a promising strategy for the prevention of liver cancer.

The immunomodulatory effects of indoleamine 2,3-dioxygenase (IDO) are ascribed to its ability to catalyze the breakdown of the L-tryptophan along the L-kynurenine pathway. Because blasts from patients with acute myeloid leukemia (AML) express IDO, the goal of this study was to investigate the role of L-kynurenine as a prognostic marker for AML. We enrolled 48 AML patients. L-kynurenine concentrations were measured by high-performance liquid chromatography. The median serum L-kynurenine level was 1.67 M. There was no significant difference in the complete remission rate between patients with L-kynurenine < 2.4 (77%) and 2.4 M (75%). However, 3-year overall survival (OS) rates were significantly better in patients with low L-kynurenine levels (76%) than in those with high L-kynurenine levels (11%) (p < 0.0001). Furthermore, in intermediate-risk cytogenetics patients, only L-kynurenine was significantly associated with OS (p < 0.005). Multivariate analyses revealed that L-kynurenine and high leukocyte count were independent prognostic factors.

Objectives: Docetaxel is used as the first-line chemotherapy for castration-resistant prostate cancer (CRPC), but docetaxel resistance occurs in part owing to induction of P-glycoprotein (P-gp) encoded by multidrug resistance protein 1 (MDR1) gene. A recently developed taxane-cabazitaxel-has poor affinity for P-gp and is thereby effective in docetaxel-resistant CRPC. It has been recently demonstrated that exosomes in the body fluids could serve as a diagnostic marker because they contain proteins and RNAs specific to the cells from which they are derived. In this study, we aimed to investigate if P-gp in blood exosomes could be a marker to diagnose docetaxel resistance and select a taxoid for patients with CRPC. Methods and materials: Exosomes were isolated by differential centrifugation from docetaxel-resistant prostate cancer (PC-3) cells (PC-3R) and their parental PC-3 cells and from the serum of patients. Silencing of P-gp was performed by small interfering RNA transfection. Protein expression was examined by Western blot analysis. Viability of cells treated with docetaxel or cabazitaxel was determined by water soluble tetrazolium salt (WST) assay. Results: The level of P-gp was higher in exosomes as well as cell lysates from PC-3R cells than in those from PC-3 cells. Cabazitaxel effectively killed PC-3R cells, and MDR1 knockdown improved the sensitivity of PC-3R cells to docetaxel but not to cabazitaxel. The P-gp level in blood exosomes was relatively higher in clinically docetaxel-resistant patients than in therapy-naive patients. Conclusions: Our results suggest that detection of P-gp in blood exosomes, which is involved in resistance to docetaxel but not to cabazitaxel, could be useful to diagnose docetaxel resistance and select an appropriate taxoid for patients with CRPC-docetaxel or cabazitaxel. (C) 2015 Elsevier Inc. All rights reserved.

Indoleamine 2,3-dioxygenase (IDO) catalyzes the rate-limiting step in the metabolism of tryptophan along the kynurenine pathway. In tumors, increased IDO activity inhibits proliferation and induces apoptosis of T cells and natural killer cells. We investigated the therapeutic potential of IDO inhibitor 1-methyl-d-tryptophan (d-1MT) with cyclophosphamide (CY) in a mouse model of lymphoma. To examine the effect of d-1MT, mice were killed on day 28. Serum concentrations of l-kynurenine and l-tryptophan were measured by high-performance liquid chromatography. Regulatory T cells (Tregs) were counted by flow cytometry, and mRNA expressions of IDO1, Foxp3, IFN-gamma, and COX-2 were examined by quantitative real-time reverse transcription-polymerase chain reaction. d-1MT+CY combination treatment significantly inhibited tumor growth as compared to either treatment alone. There were no significant differences in the serum l-kynurenine/l-tryptophan ratio or the IDO1 expression level in the tumors among the treatment groups. The expression levels of IFN-gamma and COX-2 mRNA in tumor-draining lymph nodes (TDLNs) were found to be significantly up-regulated in the CY and d-1MT+CY groups. The number of Tregs in TDLNs in the d-1MT+CY group was significantly lower than that in CY groups on day 17. These results suggest that d-1MT in combination with CY is an effective treatment for lymphoma in a mouse model.

Subcutaneous sarcoidosis occurs infrequently among cases of cutaneous sarcoidosis. To our knowledge, few studies have described the sonographic characteristics of subcutaneous sarcoidosis. Here we report the sonographic characteristics of 3 cases of this condition. Our results revealed 4 features: (1) an irregular hypoechoic appearance, (2) heterogeneous echogenicity, (3) perilesional hyperechoic changes, and (4) abnormal Doppler signals. Sonography is a rapid, simple, and noninvasive procedure that is useful for initial evaluation of granulomatous lesions such as subcutaneous sarcoidosis.

Indoleamine 2,3-dioxygenase (IDO), an enzyme that degrades the essential amino acid l-tryptophan along the kynurenine pathway, exerts immunomodulatory effects in a number of diseases. IDO expression is increased in tumor tissue and in draining lymph nodes; this increase is thought to play a role in tumor evasion by suppressing the immune response. A competitive inhibitor of IDO is currently being tested in clinical trials for the treatment of relapsed or refractory solid tumors, but the efficacy of IDO inhibition in colorectal tumors remains to be fully elucidated. In this study, we investigated the effect of IDO deficiency on colon tumorigenesis in mice by genetic deletion and pharmacological inhibition. Ido1-deficient((-/-)) mice were crossed with Apc(Min/+) mice or were administered azoxymethane with or without dextran sodium sulfate. Ido1 deficiency did not lead to significant differences in the size and number of colon tumors. Similarly, the pharmacological inhibition of IDO using 1-methyltryptophan (1-mT) also resulted in no significant differences in tumor size and number in Apc(Min/+) mice. However, Ido1 deficiency altered the immune response in the tumor microenvironment, showing a significant increase in mRNA expression of pro-inflammatory cytokines and a significant decrease in the number of Foxp3-positive regulatory T cells in the colon tumors of Ido1((-/-)) mice. Importantly, 1-mT treatment also significantly altered cytokine expression in the colon tumor tissues. These results suggest that IDO inhibition alone cannot sufficiently suppress colon cancer development in mice despite its immunomodulatory activity in the tumor microenvironment.

Background and Aim The liver has a high capacity of its regeneration. Most hepatic cells are quiescent unless otherwise stimulated such as their injury or ablation. A previous study suggest that pre-activated hepatic cells have a positive effect on their regeneration. In this study, we examined whether the pre-activated hepatic cells for regeneration accelerate the subsequent liver regeneration. Methods We administered a single injection of carbon tetrachloride (CCl4) to mice 7 days before partial hepatectomy (PHx). Liver weight/body weight ratio and several parameters for cell proliferation such as mitotic index and the number of Ki67 positive cells in the liver were examined after PHx as indexes of liver regeneration. Results Compared to control mice, those pre-stimulated with CCl4 showed earlier liver regeneration 48 h after PHx. Regardless of their accelerated regeneration, pre-stimulated mice showed less cell proliferation than did control mice during liver regeneration. Hepatic fibrosis was not observed in both control and CCl4-pretreated mice after PHx. Mice pre-treated with CCl4 showed the higher matrix metalloproteinase 9 (MMP9) expression than those pre-treated with olive oil. When matrix metalloproteinase 9 (MMP9) activity was inhibited, the pre-stimulated mice did not demonstrate accelerated liver regeneration and they returned to the original state for cell proliferations after PHx. Conclusions Pre-activated liver by CCl4 promoted its subsequent regeneration after PHx. This was not a cause of fibrosis and partly dependent on MMP9 pre-activity rather than cell proliferation in liver. Our findings would not only provide a novel strategy for liver regeneration without cell proliferation as much as possible and also propose a new method for liver transplantation.

The aim of this study was to quantitatively assess the echo intensity of the supraspinatus muscle and compare magnetic resonance imaging and ultrasound findings for 27 patients (12 women, 15 men, 65.8 +/- 11.5 y). Tear size and fatty infiltration were determined by magnetic resonance imaging; five stages were assigned based on Goutallier's classification. Gray-scale histogram analysis was used for ultrasound assessment, which was performed in both subcutaneous fat and supraspinatus muscle in three different regions; the echo intensity ratio was the ratio of echo intensity in subcutaneous fat to that in the supraspinatus muscle. Sonograms of 27 shoulders revealed 3 shoulders with a partial tear, and 4 with a small tear, 6 with a medium tear, 6 with a large tear and 4 with a massive tear; 4 shoulders had no tear. Supraspinatus muscle echo intensity and echo intensity ratio were significantly lower in the stage 0 and 1 than in stages 2-4. Our study suggests that ultrasound can quantitatively and objectively assess fatty infiltration in the rotator cuff muscle. (E-mail: tsuneo_w@gifu-u.ac.jp) (C) 2015 World Federation for Ultrasound in Medicine & Biology.