利用细胞外基质大规模扩增临床级人脂肪间充质干细胞

背景:如何运用无血清培养体系大规模扩增处于未分化状态的脂肪间充质干细胞,并使其保持"干性"是脂肪间充质干细胞临床应用转化中急待解决的难题。目的:建立含细胞外基质的脂肪间充质干细胞体外培养系统,验证其扩增细胞的高效性、有效性及安全性。方法:在无血清培养条件下,将体外分离得到的脂肪间充质干细胞分别接种在包被细胞外基质的培养板和传统二维塑料培养板上。经过体外扩增后,比较2种条件下细胞数量、细胞表面标记物表达、细胞衰老状况以及体外多向分化能力(诱导成脂、成骨和成软骨)的差异,考察脂肪间充质干细胞在含细胞外基质的培养条件下扩增后的临床安全性。结果与结论:脂肪间充质干细胞扩增到第5代时,包被细胞外基质培养板的细胞产量已经是传统二维塑料培养板的10倍以上,流式细胞检测表明,在含细胞外基质条件下扩增的脂肪间充质干细胞仍保持了干细胞表面特定标记物的表达。细胞衰老检测结果显示,使用包被细胞外基质的培养板扩增脂肪间充质干细胞至第15代时,细胞仍几乎无老化现象,而使用二维塑料培养板扩增的细胞在第5代时已出现明显老化,传代后细胞增殖能力明显下降。体外多向诱导分化实验显示,脂肪间充质干细胞在含细胞外基质条件下扩增至第15代时仍具有成脂、成骨和成软骨的分化功能,并且与第5代时没有明显差异,同时显著优于传统培养条件下的第5代脂肪间充质干细胞。染色体核型分析及小鼠成瘤性试验结果表明,脂肪间充质干细胞在含细胞外基质条件下扩增后仍具备临床应用的安全性。以上结果证实,含细胞外基质的无血清培养系统可以更高效且安全地扩增出具有临床应用潜能的脂肪间充质干细胞。     

人脂肪源性干细胞多潜能分化特性

目的原代分离培养人脂肪干细胞(ADSCs),探讨细胞增殖及多向分化,间充质干细胞相关特性。方法取人吸脂术的脂肪组织通过酶消化法分离培养ADSCs,观察细胞形态,MTT法检测细胞增殖活性,流式细胞术检测细胞周期和表面抗原的表达,用茜素红、甲苯胺蓝和油红O染色鉴定向骨、软骨及脂肪诱导分化。结果人ADSCs呈长梭形、旋涡状生长,传至第15代的ADSCs仍具较强的增殖能力,ADSCs具有干细胞特性,高表达标记CD90和CD44的间充质干细胞,不表达内皮细胞标记CD31,而CD49d低表达,CD106阴性。成骨诱导后可见钙结节形成并被茜素红染成紫红色,软骨诱导后分泌大量蛋白多糖,被甲苯胺蓝染成蓝色,成脂诱导后细胞内可见大量脂滴被油红O染色红色。结论人脂肪干细胞可分化成间充质干细胞,具有稳定增殖和成骨、成软骨和成脂等多向分化潜能。     

体外培养兔脂肪源性间充质干细胞的成骨成脂分化

背景:脂肪源性间充质干细胞具有自我更新能力且在体外特定条件下具有多向分化潜能,在临床上具有广泛的应用前景。然而,脂肪源性间充质干细胞的分离培养仍存在诸多困难与不足。目的:体外分离培养获得兔脂肪源性间充质干细胞,对其形态学、生物学特性进行观察,并鉴定其向成骨、成脂分化的潜能。方法:切取兔颈背区皮下脂肪,用胶原酶消化法分离兔脂肪源性间充质干细胞,进行体外培养,流式细胞仪检测细胞表面标志物,CCK-8法检测细胞活性并绘制细胞生长曲线。第4代兔脂肪源性间充质干细胞向成脂、成骨诱导分化后进行油红O染色、茜素红染色、碱性磷酸酶染色,观察其成脂、成骨分化潜能。结果与结论:兔脂肪源性间充质干细胞呈长梭形漩涡样贴壁生长,能稳定传代至第10代,增殖能力强;流式细胞仪检测可高表达CD29、CD90及CD44,而CD34和CD45表达较低;成脂诱导后的兔脂肪源性间充质干细胞油红O染色呈阳性;成骨诱导后的兔脂肪源性间充质干细胞碱性磷酸酶和茜素红染色均呈阳性,以上结果显示实验成功分离培养出兔脂肪源性间充质干细胞,获得的细胞生长稳定,增殖活跃,高表达间充质干细胞的表面抗原以及具有向成骨、成脂等多向分化的潜能,有望为骨组织工程提供理想的种子细胞。     

微重力对干细胞增殖分化影响的研究进展

微重力环境会影响干细胞的生长、增殖和分化。既往的部分研究表明,微重力环境下培养的间充质干细胞的生长速度较正常重力条件下培养更快,其原因可能是细胞团体积的增大。但是有研究指出微重力能够通过影响细胞周期抑制间充质干细胞增殖。在分化方面,微重力能够抑制间充质干细胞的成骨分化,促进其成脂肪分化,但是对其成软骨分化影响仍存争议。有研究者对微重力培养的间充质干细胞进行基因测序提示其成骨分化相关基因表达降低,同时伴有成脂肪分化的基因表达增高。微重力可能通过整合素/丝裂原活化蛋白激酶和PPAR-这两条信号通路抑制干细胞成骨分化作用,而微重力如何影响成软骨分化以及成脂分化的机制仍缺乏相关研究。同时,微重力能够有效地维持间充质干细胞的多能性和自我更新能力。微重力对于间充质干细胞的影响为组织工程的进一步发展提供了探索依据。     

大鼠来源滑膜间充质干细胞的成软骨分化

背景:相比其他组织来源的间充质干细胞,滑膜间充质干细胞有着较强的成软骨特性和克隆能力,因此将是软骨组织工程中最有前景的种子细胞之一。目的:培养及体外扩增SD大鼠滑膜间充质干细胞,鉴定其多向分化潜能及在添加生长因子后三维立体培养条件下的成软骨能力。方法:无菌条件下获取SD大鼠滑膜组织,Ⅰ型胶原酶消化法分离大鼠滑膜间充质干细胞。体外扩增、培养,取第3代滑膜间充质干细胞进行吉姆萨、生长曲线测定、成脂诱导、成骨诱导和三维条件下成软骨诱导,成软骨诱导21 d后通过甲苯胺蓝染色、Ⅱ型胶原免疫组化染色及RT-PCR对成软骨诱导后产物进行检测。结果与结论:获取的大鼠滑膜细胞具有间充质干细胞的特性,滑膜间充质干细胞在体外培养呈成纤维样形态,并维持着多向分化的能力。使用生长因子诱导软骨细胞21 d后,可见软骨样组织,蛋白聚糖和Ⅱ型胶原可以在甲苯胺蓝染色和Ⅱ型胶原免疫组化染色后被检测到。RT-PCR检测结果显示软骨诱导分化后细胞中Ⅱ型胶原和蛋白聚糖mRNA呈阳性表达。提示大鼠来源的滑膜间充质干细胞具有成软骨能力。     

脐带来源间充质干细胞在成脂培养条件下骨形态发生蛋白2的表达

背景：脐带间充质干细胞在成脂培养条件下成脂相关信号因子过氧化物酶体增殖体激活受体γ的表达水平增高,同时成骨相关信号因子骨形态发生蛋白的表达水平也增高。 目的：检测成脂诱导条件下脐带间充质干细胞的过氧化物酶体增殖体激活受体γ及骨形态发生蛋白2的表达水平变化,并对结果进行初步探讨。 方法：取脐带来源的间充质干细胞,以成脂诱导体系对细胞进行诱导分化培养,倒置显微镜下观察细胞体外培养生长情况;油红O染色法观察成脂现象,茜素红及von kossa染色观察是否有沉淀形成;荧光定量PCR方法检测成脂相关因子过氧化物酶体增殖体激活受体γ及骨形态发生蛋白2的表达变化情况。 结果与结论：获得脐带来源间充质干细胞,并成功进行了成脂诱导分化。荧光定量PCR检测发现在成脂诱导条件下脐带间充质干细胞的过氧化物酶体增殖体激活受体γ和骨形态发生蛋白2的表达水平全都呈升高趋势,但是前者对分化方向的调控起主要作用。     

脐血间充质干细胞生物学特性及其成骨成脂分化潜能

背景:对于脐血来源间充质干细胞的研究是干细胞研究领域的重点和热点,但目前国内外研究对其报道尚较少,许多方面存在争议。目的:观察人脐血间充质干细胞的生物学特性,并探讨其向成骨、成脂肪细胞诱导分化的能力。方法:从不同胎龄脐血中分离培养间充质干细胞;通过倒置相差显微镜及透射电镜观察细胞的形态、生长增殖情况及其超微结构;并描绘细胞生长曲线;用流式细胞仪对细胞表面标志物进行检测。分别用成骨及成脂诱导液对脐血间充质干细胞进行诱导,通过茜素红染色检测脐血间充质干细胞向成骨细胞诱导分化的能力;通过油红O染色检测其向脂肪细胞诱导分化的能力。结果与结论:倒置相差显微镜下观察脐血间充质干细胞贴壁生长,呈成纤维细胞样外观,细胞呈螺旋状排列;透射电镜观察脐血间充质干细胞细胞核大,胞核比例大,细胞器少,为低分化细胞;原代及传代培养的脐血间充质干细胞生长曲线均呈S型,第3,5代细胞增殖能力最强。流式细胞仪检测结果显示,脐血间充质干细胞均稳定表达与间充质干细胞相关的表面抗原标志物CD29,CD44和CD90等,不表达造血标志CD34和CD45。脐血间充质干细胞成骨诱导后3周时茜素红染色可检测到大量钙化基质的形成;成脂诱导3周时油红O染色可检测到胞质中脂滴的形成。提示脐血间充质干细胞的形态特征、生长增殖特点及细胞表面标志物等生物学特性与骨髓间充质干细胞相似,具有强大的生长增殖与自我更新能力。脐血间充质干细胞在体外诱导条件下可以向成骨细胞及脂肪细胞等间质组织细胞定向分化。     

兔下颌骨来源骨髓间充质干细胞的体外培养及生物学特性*

背景：以往研究表明骨髓间充质干细胞的获取来源主要是股骨或髂骨,但下颌骨来源骨髓间充质干细胞的研究至今少有报道。 目的：观察兔下颌骨来源的骨髓间充质干细胞体外分离、培养及其生物学特性。 方法：体外分离培养兔下颌骨骨髓间充质干细胞,取第2或3代检测。MTT法检测细胞增殖,克隆形成试验检测细胞的克隆形成率变化,并对其进行成骨和成脂肪诱导分化。 结果与结论：MTT法检测细胞增殖,细胞生长曲线显示下颌骨骨髓间充质干细胞经历潜伏期、对数生长期和平台期。细胞克隆形成实验显示,细胞呈成纤维集落形成单位外观。茜素红、油红O染色结果显示,成骨诱导、成脂诱导后形成钙结节及脂滴。结果证实,兔下颌骨分离出的骨髓间充质干细胞有强大的自我复制及增殖能力,具有多向诱导分化的潜能。     

人脂肪间充质干细胞成功诱导分化为脂肪细胞

目的分离培养人脂肪间充质干细胞(h ADSCs),探讨h ADSCs生长特性及分化为脂肪细胞的能力。方法采用Ⅰ型胶原酶消化和贴壁筛选联合培养方法,从人腹部吸脂术所抽取的脂肪组织中分离培养间充质干细胞,传代,绘制其生长曲线,免疫细胞化学染色检测细胞表面标志物以鉴定所分离细胞;利用三联诱导法诱导人脂肪间充质干细胞向脂肪细胞分化,并进行油红O染色鉴定,显微镜下观察。结果原代人脂肪源间充质干细胞贴壁生长,为形态相对均一的梭形细胞,呈平行排列生长,生长曲线呈"s"型分布,间充质干细胞相关标志物CD44、CD49d高表达,而CD34、CD106则呈阴性。三联诱导法成功诱导人脂肪源间充质干细胞向脂肪细胞分化,诱导7d后镜下可见脂滴的出现,12d后最为显著,油红O染色脂滴着红色。结论 h ADSCs经过体外扩增及成脂诱导成功分化为脂肪细胞,可成为组织工程理想种子细胞。     

3种不同来源CD146阳性间充质干细胞亚群的生物学特性比较

目的比较脐带间充质干细胞(UCMSCs)、脂肪间充质干细胞(AMSCs)以及骨髓间充质干细胞(BM-MSCs)中CD146^+细胞亚群的生物学特性。方法用磁珠分选法分选不同组织来源的间充质干细胞,获得高纯度CD146^+亚群;用流式细胞计量术分析表型;透射电子显微镜观察细胞结构;成脂诱导分化后油红O染色;RT-qPCR检测成脂相关基因LPL、C/EBPα和PPARγ表达;成骨诱导分化后ALP染色,检测成骨相关基因ALP、OPN和RUNX2表达;检测细胞干性基因及血管生成相关基因表达;检测细胞体外成管能力。结果3种组织来源CD146^+MSCs具有相似的形态,表达除CD106外相似的细胞表面标志分子。与其他两种细胞比较,CD146^+AMSCs表达更高的干性基因OCT-4、SOX2和NANOG。在相同的诱导时间,CD146^+UCMSCs成脂和成骨能力较其他两种来源的CD146^+MSCs弱。3种组织来源的CD146^+MSCs均可表达血管内皮相关刺激因子BFGF、VEGF、Ang-1和EGF,但CD146^+BM-MSCs具有更强的体外成管能力。结论3种不同来源的CD146^+MSC具有不同的生物学特性,为进一步研究不同组织来源的间充质干细胞的特定应用提供了基础。     

Secular change in menarche in women in Madrid

The age at menarche was estimated by recollection in 1617 women between the ages of 18 and 60 in Madrid and a nearby suburb, Pinto. The population of Pinto is working-class and the Madrid group, taken from residential neighbourhoods , belongs to the upper middle class. In both groups we found a diminution in average age at menarche, from 14.04 to 13.02 years in Madrid and from 14.55 to 13.16 years from about 1935 to about 1965 in Pinto. These changes have been more intense in the group which is less well-off economically, where living conditions have varied much more drastically.     

Intestinal helminthiasis in school children in Haiti in 2002

A survey on intestinal helminths in school children was conducted in Haiti in 2002. This first nationwide study involving the entire country was stratified by department according to urban and rural zones using the cluster method. Focusing on elementary school children (n=5792; age range 3 to 20 years), it involved 26 urban and 49 rural schools randomly selected. Stools were preserved in formalin and examined by the Ritchie technique. Thirty-four per cent of stools (1981/5792) tested positive for intestinal helminths with the following parasites identified: Ascaris lumbricoides (27.3%), Trichuris trichiura (7.3%), Necator americanus (3.8%), Hymenolepsis nana (2%), Taenia sp. (0.3%) and Strongyloides stercoralis (0.2%). The helminth prevalence was higher in rural (38.4%) compared to urban areas (30%). There was no significant difference in prevalence by sex and age. The importance of geohelminths changed from one department to another with the highest prevalence found in the Southern department of Grande Anse (73.7%) and the lowest prevalence in the Center department (20.6%). Five out of the country's nine departments had a similar prevalence varying from 25.5% to 28.2%. Intestinal helminthic polyparasitism was observed in a percentage of infested school children comprise between 3.4% and 28.6% according in relation to the geographical area. A program to fight against geohelminths in school children should be initiated as a public health priority. Albendazole is the drug of choice. Frequency of drug distribution should be based on the prevalence of geohelminths in each department.     

Changes in the hypothalamic nuclei in in experimental allergy

Summary In rabbits subjected to prolonged sensitization and in which the Arthus phenomenon was induced there was a marked reaction of the hypothalamic nuclei. Staining by Gomori's method indicated a cellular swelling, loss of granules, and protoplasmic vacuolization in the supraoptic nucleus. There was a considerable increase in the size of the cross-sectional area of the cells. The same effects were much less well shown in the paraventricular nucleus. These results show that marked signs of increased neurosecretion developed in the animals at the height of the Arthus phenomenon.(Presented by Active Member AMN SSSR V. V. Parin) Translated from Byulleten Éksperimental'noi biologii i Meditsiny, Vol. 55, No. 4, pp. 110–113, April, 1963.     

Experience in adult population in dengue outbreak in Delhi

A dengue outbreak has recently hit the Indian capital. We studied the clinical profile of adult patients. Five hundred and sixty patients of dengue infection were admitted in a specially created ward according to the criteria laid down by WHO. Haematemesis (28.28%), epistaxis (26.78%) and malena (14.28%) were some of the common presentations. Similarly lymphadenopathy, especially cervical (30.89%), palatal rashes (26.96%) and hepatomegaly (23.75%) were the most commonly encountered findings on physical examination. Most of the cases were of dengue fever with haemorrhage and only 2.5% cases were classified under dengue haemorrhagic fever or dengue shock syndrome. The average hospital stay was 3.4 days but only 9.8 hours in the eleven patients who died, suggesting their late arrival in preterminal situation giving little time for resuscitation. Thrombocytopenia was not a feature and only 12.85% patients had platelet count less than 70,000/cmm. Most of the patients who were admitted with thrombocytopenia, showed normalization in their platelet counts in next few days. Serological examination demonstrated evidence of recent dengue infection in 41.17% patients. Few patients required blood or platelet concentrate transfusion. Eleven patients died, three due to DIC, one of intracranial haemorrhage and seven due to massive gastric haemorrhage. Rest of the patients recovered completely. Thus we can conclude that recent outbreak in Delhi was of dengue fever with haemorrhage and mortality was very low in patients who came early to the hospital.     

Development in in vitro toxicology

There are three principal pressures driving the development of in vitro toxicology: (1) the need for more efficient testing systems to cope with the large number of xenobiotics currently being developed; (2) public pressure to reduce animal experimentation; and (3) a need for a better understanding of the mechanisms of toxicity. Within this, in vitro toxicology is focused on local, systemic, and target-organ toxicity. It is becoming increasingly apparent that a step or decision-tree approach using input of a variety of experimental data (physicochemical properties, biokinetics, cytotoxicity) provides the most efficient system for predicting toxicity. Examples of the use of in vitro toxicity systems for prediction of systemic toxicity and target-organ (liver) toxicity are presented.