段階的脱グリコシル化法によるIgA1ヒンジ部O結合型糖鎖構造解析

藤田医科大

Role of C-Terminal Region of HA-33 Component of Botulinum Toxin in Hemagglutination

Clostridium botulinum D型1873株とC型Yoichi株の産生するプロジェニター毒素から得られた1種類のサブコンポーネントである血球凝集素（HA-33）は、C及びD型参照株のそれより少し小さい分子サイズであるが、他のコンポーネントのの大きさに違いがないことが、SDS-PAGEを用いて見いだされた。すなわち、HA-33のN-及びC-末端シーケンス分析に基つき、両株のHA-33淡白において特異的なサイトでC-末端から33アミノ酸残基の欠落があることが見いだされた。両株のプロジェニター毒素は、参照株毒素の血球凝集力価2かそれ以下の弱い血球凝集活性を示すが、赤血球に吸着することはできない。これらの結果はHA-33の短いC-末端部分が、ボツリヌスプロジェンター毒素の血球凝集活性において重要な役割を果たしていることを示す。さらに、シーケンスモチーフの探索により、HA-33のC-末端部分は炭化水素認識サブドメインを持っていることが推測された

Aberrantly Glycosylated IgA1 in IgA Nephropathy: What We Know and What We Don’t Know

IgA nephropathy (IgAN), the most common primary glomerular disease worldwide, is characterized by glomerular deposition of IgA1-containing immune complexes. The IgA1 hinge region (HR) has up to six clustered O-glycans consisting of Ser/Thr-linked N-acetylgalactosamine usually with β1,3-linked galactose and variable sialylation. Circulating levels of IgA1 with abnormally O-glycosylated HR, termed galactose-deficient IgA1 (Gd-IgA1), are increased in patients with IgAN. Current evidence suggests that IgAN is induced by multiple sequential pathogenic steps, and production of aberrantly glycosylated IgA1 is considered the initial step. Thus, the mechanisms of biosynthesis of aberrantly glycosylated IgA1 and the involvement of aberrant glycoforms of IgA1 in disease development have been studied. Furthermore, Gd-IgA1 represents an attractive biomarker for IgAN, and its clinical significance is still being evaluated. To elucidate the pathogenesis of IgAN, it is important to deconvolute the biosynthetic origins of Gd-IgA1 and characterize the pathogenic IgA1 HR O-glycoform(s), including the glycan structures and their sites of attachment. These efforts will likely lead to development of new biomarkers. Here, we review the IgA1 HR O-glycosylation in general and the role of aberrantly glycosylated IgA1 in the pathogenesis of IgAN in particular

Role of C-Terminal Region of HA-33 Component of Botulinum Toxin in Hemagglutination

Clostridium botulinum D型1873株とC型Yoichi株の産生するプロジェニター毒素から得られた1種類のサブコンポーネントである血球凝集素（HA-33）は、C及びD型参照株のそれより少し小さい分子サイズであるが、他のコンポーネントのの大きさに違いがないことが、SDS-PAGEを用いて見いだされた。すなわち、HA-33のN-及びC-末端シーケンス分析に基つき、両株のHA-33淡白において特異的なサイトでC-末端から33アミノ酸残基の欠落があることが見いだされた。両株のプロジェニター毒素は、参照株毒素の血球凝集力価2かそれ以下の弱い血球凝集活性を示すが、赤血球に吸着することはできない。これらの結果はHA-33の短いC-末端部分が、ボツリヌスプロジェンター毒素の血球凝集活性において重要な役割を果たしていることを示す。さらに、シーケンスモチーフの探索により、HA-33のC-末端部分は炭化水素認識サブドメインを持っていることが推測された

Purification of Fully Activated Clostridium botulinum Serotype B Toxin for Treatment of Patients with Dystonia

Clostridium botulinum serotype B toxins 12S and 16S were separated by using a beta-lactose gel column at pH 6.0; toxin 12S passed through the column, whereas toxin 16S bound to the column and eluted with lactose. The fully activated neurotoxin was obtained by applying the trypsin-treated 16S toxin on the same column at pH 8.0; the neurotoxin passed through the column, whereas remaining nontoxic components bound to the column. The toxicity of this purified fully activated neurotoxin was retained for a long period by addition of albumin in the preparation

RELATIONSHIP BETWEEN SALT INTAKE AND GNRI IN ELDERLY DIALYSIS PATIENTS

While the recommended salt intake in dialysis patients is no more than 5g/day in the KDOQI guideline, and 6g/day in the JSH 2009 guideline, reducing salt consumption is difficult on the traditional Japanese diet. If a patient is malnourished, a low-salt diet poses a risk of aggravating the nutritional deficiency. Since elderly dialysis patients have nutritional deficiencies underlying their condition, the recommended low-salt diet may prevent these patients from receiving adequate nutrition. In the present study, factors associated with nutritional status in the elderly were assessed using the Geriatric Nutritional Risk Index (GNRI), which is considered to correlate with predictor of mortality among dialysis patients. Participating patients were anuric, had been maintained on dialysis for at least 2 years, and were 65 years of age or older. Factors assessed for their possible correlations with GNRI were primary disease, presence of spouse, presence of cohabiting family, weight gain, and estimated salt intake. We analyzed 36 patients (age 74.3±5.4 years, 50% males). GNRI was 90.9±7.7, and salt intake (8.02±1.94) correlated with GNRI (r=0.41, P=0.02). No correlations were detected for the presence of spouse or cohabiting family, which would have contributed to nutrition. In conclusion, the higher the salt intake, the better GNRI tended to be. This raised the possibility that it would be advantageous to avoid excessive salt restriction in nutritional training