Monoclonal antibody against bacterial lipopolysaccharide cross-reacts with DNA-histone

（1）目　的　　自己抗体の産生機構を明らかにするため、リポポリサッカライド（LPS）に対する単クローン抗体と核抗原との反応性を検討した。（2）研究方法　単クローン性抗LPS抗体は、Salmonella Minnesota Re595株由来のLPSを抗原としてハイブリドーマを作製して得た。抗核抗体の検出には、ラット肝を基質として蛍光抗体法を用い、さらに二重免疫抗散法に基づき、精製核抗原との反応性を確認した。なお、抗LPS抗体は酸素免疫測定法により、LPSのエンドトキシンはリムルスを基質に用いて測定した。（3）結　果１）抗LPSモノクロナール抗体（RSO１）の抗核抗体活性　LPS免疫マウスより得た140ウエルのハイブリドーマのうち、抗LPS抗体活性をもち、びまん型の強い抗核抗体活性を有するハイブリドーマRSO１株を確立した。本抗体は１gM　Kappaで、その抗核抗体活性はDNA-ヒストンにより完全に吸収された。さらに核材の塩酸処理およびヒストン再添加後の反応および二重免疫拡散法によるDNAーヒストンとの沈降線形成などの結果より抗DNA-ヒストン抗体活性を有することを確認した。またRSO１抗体は、in vitroでLE体形成能を有していた。２）RSO１の抗LPS抗体活性　RSO１と各種細菌由来のLPSとの反応性を検討した結果、Salmonella M.Re595株由来のLPSとのみ特異的に反応することが示された。３）RSO１のLPSと核抗原との交差反応性　RSO１をSalmonella M.Re株で吸収すると抗核抗体活性は消失した。またRSO１の抗LPS抗体活性は、DNA-ヒストンの添加により競合的に阻害され、RSO１が核成分であるDNA-ヒストンとLPSの両者に特異的抗体活性を有することが示された。（4）考　察　細菌固有のLPSを用いて免疫することにより、抗DNA-ヒストン抗体が産生されることを明らかにした。この成績は、抗核抗体のなかには外来性抗原によって生ずるものがあり、それが自己抗原と交差反応する可能性を示唆する。　抗DNA-ヒストン抗体は全身性エリテマトーデス（SLE）に特異性の高い自己抗体であるので、SLEの発症に関与する一要因としてLPSの果たす役割に注目し、さらに追求する必要性が示された。Thesis--University of Tsukuba, D.M.S.(B), no. 346, 1986.11.3

The Partial Duplication of the 5′ Segment of KMT2A Revealed KMT2A-MLLT10 Rearrangement in a Boy with Acute Myeloid Leukemia

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Ethosuximide completely suppressed epileptic negative myoclonus in childhood localization-related epilepsy

We report two cases of localization-related epilepsy manifesting frequent brief atonia. The patients were assumed to have epileptic negative myoclonus (ENM), and were successfully treated with ethosuximide (ESM). Both exhibited hemi-orofacial twitches during sleep, and interictal electroencephalography (EEG) showed paroxysms over the contralateral posterior-temporal and centroparietal regions. Incessant atonia appeared at nine and 10 years of age accompanied by motor paresis. Ictal EEG showed irregular high-voltage spike-waves predominantly over bilateral centroparietal regions. Carbamazepine and zonisamide were ineffective in controlling, or even aggravated ENM. The addition of ESM resulted in immediate and complete disappearance of ENM and partial motor seizures along with an improvement of motor paresis. The first case was assumed to have idiopathic etiology because of normal development before the onset of epilepsy, while the second case was considered to have cryptogenic etiology based on a pre-existing intellectual disability. Hence, we recommend that ESM should be considered for the treatment of ENM that develops during the course of localization-related epilepsy, regardless of the etiology. However, further studies are still needed to evaluate the effects of ESM in the treatment of ENM

Hospital-based care utilization of children with medical complexity in Japan

BackgroundFew studies have investigated the hospital‐based care utilization of children with medical complexity (CMC) in Japan. This study examined the frequency and differences in hospital‐based care utilization for CMC according to the level of medical complexity (moderate and severe).MethodsMedical records of three pediatric tertiary hospitals in one prefecture were examined in 2014. We examined the number of outpatient visits and of admissions to the hospital for CMC in the 5 years after the introduction of home medical care.ResultsOf 92 CMC, 55 had medical complexity that was moderate (CMC‐moderate) and 37 had medical complexity that was severe (CMC‐severe). The number of CMC who had medical care introduced at home had increased year by year, especially that of CMC <2 years old; the number of older CMC (i.e. 7–17 years old) had also increased in 2010–2014. The median total outpatient visits was 20 (IQR, 13–29 visits) for CMC‐moderate and 20 (IQR, 17–26 visits) for CMC‐severe in the first year. CMC‐severe had significantly longer length of admissions in the 5 years than CMC‐moderate. The number of total visits and admissions during the subsequent 4 years (from the second to the fifth year) was slightly decreased compared with the first year, but this was not significantly different.ConclusionsCMC had high utilization of hospital‐based care, and consistently utilized hospital‐based care in the 5 years after the introduction of home medical care. Further study is needed to examine both hospital‐based and home/community‐based services use

Expression profiling of genes related to asthma exacerbations

Background Asthma is a chronic airway inflammatory disease; however, the molecular mechanisms that underlie asthma exacerbation are only partially understood.Objective To identify gene expression signatures that reflect the acute exacerbation of asthma, we examined the differential expression of genes during asthma exacerbation and stable condition by using microarray analysis.Methods The subjects were mite-sensitive asthmatic children and non-asthmatic control children. The children were divided into four groups (AE: asthma exacerbation, n=12; SA: stable asthma, n=11; IC: infected control, n=6; and NC: non-infected control, n=5). Total RNA was extracted from peripheral blood mononuclear cells and subjected to microarray analysis with Illumina Human Ref8 BeadChip arrays. Welch\u27s t-test was performed to identify genes whose expression was altered during asthma exacerbation. Quantitative real-time RT-PCR was performed on samples collected from 43 asthmatic children and 11 control children to verify the microarray results.Results The expression of 137/16 genes was significantly up/down-regulated during asthma exacerbation assessed by microarray analysis. Of the genes, 62 were also differentially expressed during upper respiratory infection. Many of the asthma exacerbation related genes were involved in defence responses and responses to external stimuli, but these associations disappeared after excluding the infection-related genes. Quantitative real-time RT-PCR confirmed that the genes related (S100A8 and GAS6) and unrelated to infections (CD200 and RBP7) were differentially expressed during asthma exacerbation (P<0.01).Conclusions Previously unidentified immune responses during asthma exacerbation may provide further clarification of the molecular mechanisms underlying asthma

Generation of a bile salt export pump deficiency model using patient-specific induced pluripotent stem cell-derived hepatocyte-like cells

Bile salt export pump (BSEP) plays an important role in hepatic secretion of bile acids and its deficiency results in severe cholestasis and liver failure. Mutation of the ABCB11 gene encoding BSEP induces BSEP deficiency and progressive familial intrahepatic cholestasis type 2 (PFIC2). Because liver transplantation remains standard treatment for PFIC2, the development of a novel therapeutic option is desired. However, a well reproducible model, which is essential for the new drug development for PFIC2, has not been established. Therefore, we attempted to establish a PFIC2 model by using iPSC technology. Human iPSCs were generated from patients with BSEP-deficiency (BD-iPSC), and were differentiated into hepatocyte-like cells (HLCs). In the BD-iPSC derived HLCs (BD-HLCs), BSEP was not expressed on the cell surface and the biliary excretion capacity was significantly impaired. We also identified a novel mutation in the 5′-untranslated region of the ABCB11 gene that led to aberrant RNA splicing in BD-HLCs. Furthermore, to evaluate the drug efficacy, BD-HLCs were treated with 4-phenylbutyrate (4PBA). The membrane BSEP expression level and the biliary excretion capacity in BD-HLCs were rescued by 4PBA treatment. In summary, we succeeded in establishing a PFIC2 model, which may be useful for its pathophysiological analysis and drug development

Identification of amino acids in antigen-binding site of class II HLA proteins independently associated with hepatitis B vaccine response

Background & aimsGenetic factors in class II human leukocyte antigen (HLA) have been reported to be associated with inter-individual variation in hepatitis B virus (HBV) vaccine response. However, the mechanism underlying the associations remains elusive. In particular, the broad linkage disequilibrium in HLA region complicates the localization of the independent effects of genetic variants. Thus, the present study aimed to identify the most probable causal variations in class II HLA loci involved in the immune response to HBV vaccine.MethodsWe performed a case-control study to assess whether HLA-DRB1, -DQB1, and -DPB1 4-digit alleles were associated with the response to primary HBV vaccination in 574 healthy Japanese students. To identify causative variants, we next assessed independently associated amino acid variants in these loci using conditional logistic regression analysis. Furthermore, to clarify the functional effects of these variants on HLA proteins, we performed computational structural studies.ResultsHLA-DRB1∗01:01, HLA-DRB1∗08:03, HLA-DQB1∗05:01, and HLA-DPB1∗04:02 were significantly associated with sufficient response, whereas HLA-DPB1∗05:01 was associated with poor response. We then identified amino acids independently associated with sufficient response, namely, leucine at position 26 of HLA-DRβ1 and glycine-glycine-proline-methionine at positions 84–87 of HLA-DPβ1. These amino acids were located in antigen-binding pocket 4 of HLA-DR and pocket 1 of HLA-DP, respectively, which are important structures for selective binding of antigenic peptides. In addition, the detected variations in HLA-DP protein were responsible for the differences in the electrostatic potentials of the pocket, which can explain in part the sufficient/poor vaccine responses.ConclusionHLA-DRβ1 position 26 and HLA-DPβ1 positions 84–87 are independently associated with anti-HBs production against HBV vaccine. Our results suggest that HBsAg presentation through these HLA pocket structures plays an important role in the inter-individual variability of HBV vaccination

Comparison of PR Intervals Determined by Fetal Magnetocardiography and Pulsed Doppler Echocardiography

&lt;b&gt;&lt;i&gt;Objective:&lt;/i&gt;&lt;/b&gt; In clinical practice, measurement of mechanical PR interval (mPR) with pulsed Doppler echocardiography is a standard method used to estimate the atrioventricular conduction time in the fetus. However, fetal echocardiography does not directly reflect the electrical properties of the heart. Technological advances in fetal magnetocardiography (fMCG) have allowed recording of the electrical PR interval (ePR) with high time resolution. The aim of this study was to clarify the differences between ePR and mPR. &lt;b&gt;&lt;i&gt;Methods:&lt;/i&gt;&lt;/b&gt; The study subjects were 295 normal human fetuses (gestational age, range 20.4–41.4 weeks) who underwent fMCG, and 135 of them underwent fetal echocardiography 15–90 min before or after fMCG. The ePR was measured using the fMCG, and the mPR was determined by two pulsed Doppler methods, simultaneous recording of the left ventricular inward and outward flow (LV in/out) (n = 135) and superior vena cava and ascending aorta (SVC/aAo) (n = 84). &lt;b&gt;&lt;i&gt;Results:&lt;/i&gt;&lt;/b&gt; The ePR showed a significant, but weak, positive correlation with gestational age (r = 0.162, p = 0.0053). The mPR was significantly longer than the ePR (p &lt; 0.0001), with mean differences of 14.6% (95% limits of agreement –10.7, 39.9) for the LV in/out method and 14.7% (95% limits of agreement –8.6, 38.0) for the SVC/aAo method. &lt;b&gt;&lt;i&gt;Conclusion:&lt;/i&gt;&lt;/b&gt; Our results point to the risk of overestimation of the atrioventricular conduction time when the mPR is used, and the need for careful interpretation of PR prolongation determined by mPR.</jats:p

Mental Health of Parents as Caregivers of Children with Disabilities: Based on Japanese Nationwide Survey

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