Neuromyelitis Optica Preceded by Brain Demyelinating Episode

Neuromyelitis optica (NMO) is considered a distinct disease from multiple sclerosis (MS) because of its pathogenesis. It is well accepted that NMO selectively affects the spinal cord and optic nerve and is not associated with brain lesions at the onset of the disease, unlike MS. We present a unique case where the patient's initial lesion was in the brain, and optic neuritis and myelitis were revealed 6 years after the brain lesion. In addition, the patient's serum antiaquaporin 4 (AQP4) antibody was positive. We consider the brain lesion to precede abnormal lesion of NMO, and the AQP4 measurement is important for diagnostics, even if it occurs with brain lesions.     

Combustion smoke exposure induces up-regulated expression of vascular endothelial growth factor,aquaporin 4, nitric oxide synthases and vascular permeability in the retina of adult rats

Retinal cells respond to various experimental stimuli including hypoxia, yet it remains to be investigated whether they react to smoke inhalation. We show here that retinal cells in rats, notably the ganglion cells, Müller cells, astrocytes and blood vessels responded vigorously to a smoke challenge. The major changes included up-regulated expression of vascular endothelial growth factor (VEGF), aquaporin 4 (AQP4) and nitric oxide synthase (NOS). VEGF expression was localized in the ganglion cells, Müller cells, astrocytes and associated blood vessels. AQP4 was markedly enhanced in both astrocytes and Müller cells. Increase in vascular permeability after smoke exposure was evidenced by extravasation of serum derived rhodamine isothiocyanate which was internalized by Müller cells and ganglion cells. The tracer leakage was attenuated by aminoguanidine and N^G-nitro-l-arginine methyl ester (l-NAME) treatment which suppressed retinal tissue NOS and nitric oxide (NO) levels concomitantly. It is suggested that VEGF, AQP4 and NO are involved in increased vascular permeability following acute smoke exposure in which hypoxia was ultimately implicated as shown by blood gases analysis. NOS inhibitors effectively reduced the vascular leakage and hence may ameliorate possible retinal edema in smoke inhalation.     

GFAP-independent inflammatory competence and trophic functions of astrocytes generated from murine embryonic stem cells

The directed generation of pure astrocyte cultures from pluripotent stem cells has proven difficult. Generation of defined pluripotent-stem-cell derived astrocytes would allow new approaches to the investigation of plasticity and heterogeneity of astrocytes. We here describe a two-step differentiation scheme resulting in the generation of murine embryonic stem cell (mESC) derived astrocytes (MEDA), as characterized by the upregulation of 19 astrocyte-associated mRNAs, and positive staining of most cells for GFAP (glial fibrillary acidic protein), aquaporin-4 or glutamine synthetase. The MEDA cultures could be cryopreserved, and they neither contained neuronal, nor microglial cells. They also did not react to the microglial stimulus lipopolysaccharide, while inflammatory activation by a complete cytokine mix (CCM) or its individual components (TNF-α, IL1-β, IFN-γ) was readily observed. MEDA, stimulated by CCM, became susceptible to CD95 ligand-induced apoptosis and produced NO and IL-6. This was preceded by NF-kB activation, and up-regulation of relevant mRNAs. Also GFAP-negative astrocytes were fully inflammation-competent. Neurotrophic support by MEDA was found to be independent of GFAP expression. In summary, we described here the generation and functional characterization of microglia-free murine astrocytes, displaying phenotypic heterogeneity as is commonly observed in brain astrocytes.     

高氧下调早产大鼠肺组织AQP5的表达

目的探讨水通道蛋白5(AQP5)在早产大鼠及吸高氧过程中的肺动态表达。方法剖宫术取出孕21d SD早产鼠,于12～24h内随机分为对照组和高氧组。分别在1、4、7、10和14d时提取肺组织,RT-PCR测定AQP5 mRNA表达,免疫组化和Western blot检测AQP5蛋白的表达。结果早产大鼠生后肺组织AQP5表达不断增强,其阳性染色主要定位于Ⅰ型肺泡上皮细胞。高氧暴露1d时,仅肺组织AQP5 mRNA表达显著高于对照组(P<0·05),而高氧暴露4、7、10及14d时,其mRNA及蛋白表达均明显减少(P<0·05或P<0·01)。结论AQP5通过调节肺水平衡,在早产大鼠肺泡化形成的关键时期发挥重要作用;高氧暴露导致AQP5表达下调是促使肺损伤发生、发展的重要因素。     

Expression of aquaporin3 in human neoplastic tissues

Niu D, Kondo T, Nakazawa T, Yamane T, Mochizuki K, Kawasaki T, Matsuzaki T, Takata K & Katoh R
(2012) Histopathology  61, 543–551 Expression of aquaporin3 in human neoplastic tissues Aims: Aquaporin3 (AQP3) is distributed widely in mammalian tissues and plays an important role in fluid homeostasis. The aim of this study was to investigate the pattern of expression of AQP3 in a variety of human neoplastic tissues and to explore its diagnostic implications. Methods and results: We studied 798 neoplastic tissues using immunohistochemistry with anti‐AQP3 antibody. We demonstrated a high positive frequency of AQP3 immunoreactivity in pituitary adenomas, salivary gland tumours, thymic tumours, adenocarcinoma of the lung and prostate, squamous cell carcinomas of the skin, oesophagus and uterine cervix, apocrine carcinoma of the breast, germinal cell tumours of the ovary and testis and urothelial carcinoma of the bladder. None of the sarcomas or central nervous system tumours showed AQP3 immunoreactivity. Most tumours with a high frequency of AQP3 positivity had corresponding or surrounding normal cells that also expressed AQP3. AQP3 was not a specific marker for benign or malignant epithelial neoplasms. Conclusion: AQP3 protein is expressed in a variety of epithelial tumours limiting its use as a diagnostic marker. Furthermore, AQP3 expression in tumour cells reflected the expression status of AQP3 in the corresponding normal cells. Our data suggest that water metabolism through AQP3 is maintained during neoplastic transformation in most human tissues.     

肺泡Ⅱ型上皮细胞的生长状况及其转分化的鉴定

目的 观察肺泡Ⅱ型上皮细胞(AECⅡ)体外培养的生长状况及转分化过程.方法 通过差速贴壁法对原代培养的AECⅡ进行分离、纯化,并将AECⅡ随机分为第0天、第2天、第4天、第6天、第8天8个时间点.利用倒置显微镜观察细胞生长情况,记录细胞数目,绘制生长曲线;锥虫蓝染色观察细胞活力;流式细胞仪观察细胞生长周期和细胞凋亡情况;电子显微镜观察细胞超微结构;采用免疫荧光技术,共聚焦显微镜观察肺表面活性蛋白(SP-C)、水通道蛋白5(AQP5)的阳性表达.结果 倒置显微镜下第 0天、第2天、第4天、第6天及第8天细胞数分别为(4.02±0.99)×108L-1、(10.41±0.24)×108L-1、(27.90±1.91)×108L-1、(27.12±0.85)×108L-1及(26.29±1.59)×108L-1,第2天与第0天、第4天与第2天细胞数比较差异均有统计学意义(Pa<0.05).第2天、第4天、第6天及第8天的细胞活力分别为(97.00±0.71)%、(97.20±0.84)%、(95.00±0.71)%及(92.80±1.30)%,第6天与第4天、第8天与第6天比较差异有统计学意义(Pa<0.05).细胞周期:空气组细胞G1期、S期细胞所占比率分别在第6天、第4天最高,但各时间点与前一时间点比较差异均无统计学意义(Pa>0.05).细胞凋亡:空气组Annexin-V+/PI-亚群在第4天所占比例最高,与第2天及第6天比较差异均有统计学意义(Pa<0.05);Annexin-V+/PI+亚群细胞所占比例在第8天时最高,但与第6天比较差异无统计学意义(P>0.05),而第6天与第4天比较差异有统计学意义(P<0.05).细胞超微结构:第6天时可见介于AECⅡ和AECⅠ之间的中间状态细胞,此类细胞在细胞表面有微绒毛,但胞质内无板层小体或胞质内有板层小体但细胞表面无微绒毛.免疫荧光:第6天可见部分细胞胞质内有呈绿色荧光的SP-C阳性表达,荧光强度较第2天、第4天减弱,伴有胞膜点状分布的呈红色荧光的AQP5阳性表达,细胞表达强度不等,表达AQP5相对较弱的细胞表达SP-C的强度相对增强.结论 原代培养的AECⅡ在培养早期增殖能力最强,细胞增殖分化能力在培养晚期降低.体外培养的AECⅡ有向AECⅠ转分化的能力.     

Aquaporin‐4 Antibodies (NMO‐IgG) as a Serological Marker of Neuromyelitis Optica: A Critical Review of the Literature

Antibodies to aquaporin‐4 (called NMO‐IgG or AQP4‐Ab) constitute a sensitive and highly specific serum marker of neuromyelitis optica (NMO) that can facilitate the differential diagnosis of NMO and classic multiple sclerosis. NMO‐IgG/AQP4‐Ab seropositive status has also important prognostic and therapeutic implications in patients with isolated longitudinally extensive myelitis (LETM) or optic neuritis (ON). In this article, we comprehensively review and critically appraise the existing literature on NMO‐IgG/AQP4‐Ab testing. All available immunoassays—including tissue‐based (IHC), cell‐based (ICC, FACS) and protein‐based (RIPA, FIPA, ELISA, Western blotting) assays—and their differential advantages and disadvantages are discussed. Estimates for sensitivity, specificity, and positive and negative likelihood ratios are calculated for all published studies and accuracies of the various immunoassay techniques compared. Subgroup analyses are provided for NMO, LETM and ON, for relapsing vs. monophasic disease, and for various control groups (eg, MS vs. other controls). Numerous aspects of NMO‐IgG/AQP4‐Ab testing relevant for clinicians (eg, impact of antibody titers and longitudinal testing, indications for repeat testing, relevance of CSF testing and subclass analysis, NMO‐IgG/AQP4‐Ab in patients with rheumatic diseases) as well as technical aspects (eg, AQP4‐M1 vs. AQP4‐M23‐based assays, intact AQP4 vs. peptide substrates, effect of storage conditions and freeze/thaw cycles) and pitfalls are discussed. Finally, recommendations for the clinical application of NMO‐IgG/AQP4‐Ab serology are given.     

Novel advances in the diagnosis and treatment of neuromyelitis optica: is there a need to redefine the gold standard?

Neuromyelitis optica (NMO) is an inflammatory disease of the central nervous system characterized by severe attacks of optic neuritis and myelitis and, unlike multiple sclerosis, was initially thought to spare the brain in the early stages. The term NMO spectrum disorder (NMOSD) was recently used to qualify restricted forms of the disorder, which include recurrent optic neuritis, relapsing transverse myelitis and some encephalitic/brainstem presentations associated with positive aquaporin4 antibodies. It was also recently found that other immunological targets such as myelin oligodendrocyte glycoprotein (MOG) may be associated with seronegative NMO patients. In the present study, we detail the moving concept of NMOSD from the recent years and propose some therapeutic strategies that are clearly different compared with multiple sclerosis treatment.     

Characteristics of aquaporin 1, 3, and 5 expression during early murine salivary gland development

Aquaporins (AQPs) are essential to coordinate the transit of water and ions through the cell membrane. In salivary glands (SGs), AQPs have been associated with saliva formation, facilitating water absorption through the epithelium during the formation of hypotonic saliva, which is then secreted into the oral cavity. Different members of the AQP family have been suggested to play distinct roles during embryonic development, highlighted by their specific expression patterns. Here, we have investigated the expression patterns of AQP-1, AQP-3 and AQP-5 by immunofluorescence at key stages of salivary gland development, utilising cultured mouse embryonic submandibular (SMG) and sublingual (SLG) glands. The expression of AQPs was compared to a mitotic marker, phospho-histone 3 (PH3), a myoepithelial marker, smooth muscle actin (SMA), and a vascular marker, CD31. Qualitative analysis revealed that AQP-1 and AQP-3 were primarily expressed during the earlier phases of SG morphogenesis and were associated with cells undergoing mitotic processes (PH3-positive). AQP-5, in contrast, was not associated to mitotic figures, but was predominantly expressed during late stages of SG morphogenesis. Our results highlight that AQPs are expressed from early stages of SG morphogenesis and exhibit complimentary expression patterns that may contribute to the morphogenesis of salivary glands.     

水通道蛋白1在小鼠口腔粘膜表达与分布

目的观察水通道蛋白1(AQP1)在小鼠口腔粘膜的表达与分布,为研究AQP1在口腔水代谢和感觉传递中的作用提供形态学依据。方法制备成年小鼠口腔各部粘膜石蜡切片,进行AQP1免疫组织化学染色。结果 AQP1免疫阳性产物在唇、颊、硬腭、软腭和舌粘膜下层的毛细血管和神经纤维上广泛表达。另外在上述部位的腺泡和腺管周围的肌上皮细胞以及舌的味蕾和丝状乳头上也有AQP1免疫阳性信号。结论 AQP1在口腔广泛分布,可能参与了唾液分泌和口腔感觉传递等生理过程。