流式细胞术测定食蟹猴血清中抗间充质干细胞抗药抗体及其应用

目的 建立一种准确、快速且灵敏度高的流式细胞法检测食蟹猴血清中抗间充质干细胞抗药抗体。方法 取间充质干细胞悬液,离心、洗涤后,加入阳性质控样品溶液或待测样品溶液与间充质干细胞孵育后,加入荧光标记的Protein L-PE溶液进行孵育,洗掉未结合的Protein L-PE,流式方法检测PE平均荧光强度。结果 该方法灵敏度为115.54 ng·mL^-1,远高于非临床研究要求的250～500 ng·mL^-1。批内和批间的精密度<20%,其他方法验证考察项结果均符合相关接受标准。结论 该方法灵敏度高,特异性强,样品操作简单,可用于快速检测食蟹猴血清中抗间充质干细胞的抗体,适用于间充质干细胞在食蟹猴体内的免疫原性研究。     

重组人白细胞介素-12对食蟹猴的反复给药毒性研究

目的:观察重组人白细胞介素-12(rhIL-12)对食蟹猴的长期毒性。方法:食蟹猴皮下注射给予rhIL-12,剂量分别为0.5,5和40μg·kg-1,每周3次,共13周。检测指标包括临床症状、血液学、血生化、免疫、血清抗体和组织病理学检查。结果:rhIL-12给药后导致动物出现腹泻、面部及眼睑部肿胀、腹股沟淋巴结肿大、溃疡、及注射局部红斑和硬结等临床症状,并出现贫血和白细胞分类异常,血液生化指标出现肝脏转氨酶升高,免疫学指标出现外周血总T淋巴细胞比例增加,CD4细胞百分率下降,CD8细胞百分率增加。第7次给药后,给药组动物产生了rhIL-12抗体。结论:食蟹猴皮下注射给予rhIL-12,毒性靶器官和组织为血液系统、肝脏、心脏、肾脏和淋巴结等免疫调节系统,其安全剂量为0.5μg·kg-1。     

骨髓间充质干细胞治疗心肌梗死的研究进展

<正>心肌梗死(myocardial infarction,MI)是指心肌的缺血性坏死,已成为当今社会严重威胁人类健康的疾病之一。尽管临床上保守的药物治疗、经皮冠状动脉介入治疗(PCI)和外科冠状动脉旁路移植手术等治疗方法的不断提高,但都无法逆转梗死期坏的心肌坏死。     

骨髓间充质干细胞的分离、培养及生物学特性

目的 探讨大鼠骨髓间充质干细胞(BMSCs)的体外分离培养方法并鉴定其生物学特性.方法 采用全骨髓贴壁细胞培养法进行BMSCs的分离培养,倒置相差显微镜下观察细胞形态及生长特性,绘制细胞生长曲线,并检测细胞在不同诱导条件下向成脂肪细胞和成骨细胞分化的能力.结果 原代大鼠BMSCs培养24 h后镜下观察大部分细胞已经贴壁,传至第三代,细胞形态均一,呈梭形、螺旋样排列.经过约2 d的适应期,3～7 d进入对数生长期,7 d后进入平台期;成骨细胞诱导18 d,茜素红染色可见明显钙结节,成脂肪细胞诱导2周后油红O染色可见明显脂质沉淀.结论 全骨髓贴壁细胞培养法操作简单、快速,可以获取形态均一、纯度较高的BMSCs.     

人骨髓间充质干细胞体外分离培养方法的比较研究

目的 比较Ficoll密度梯度离心法分离人骨髓间充质干细胞(mesenchymal stem cells,MSCs)与全骨髓培养法之间的差异,以期建立一种简便、实用的基于临床移植需要的MSCs分离方法.方法 分别应用上述两种方法分离MSCs,比较用两种方法的细胞形态、MSCs细胞得率及以及细胞表面标志的差异.结果 两种方法均能有效培养出骨髓MSCs,且获得的第二代MSCs细胞形态无明显差异,细胞形态均一,为长梭形或三角形.5 ml骨髓细胞分离培养后,Ficoll密度梯度离心法获得的MSCs细胞总数显著小于全骨髓培养法(t=.639,P＜0.01).Ficoll密度梯度离心法与全骨髓培养法获得的第二代MSC8 CD29、CD105、CD105、CD34阳性表达率的差异无统计学意义(t分别为0.809、0.659、0.277、0.191,P均＞0.05),但前者的HLA-DR阳性表达率明显低于后者,差异具有统计学意义(t=2.347,P＜0.05).结论 与Ficoll密度梯度离心法相比较,全骨髓培养法分离MSCs具有培养时间较短,细胞得率较多的优点,虽纯度相对较低,但仍是一种较好的MSCs分离方法.     

诱导人骨髓间充质干细胞向成骨细胞分化

目的探讨人骨髓间充质干细胞(mesenchymal stem cells,MSCs)向成骨细胞诱导分化的能力。方法选用不同代次的MSCs,使用条件培养基,观察细胞的形态变化,采用细胞化学和免疫组化的方法检测碱性磷酸酶、钙盐沉积及Ⅰ型胶原的表达。结果MSCs在条件培养基中,15d后可见细胞变为多边形,碱性磷酸酶和Ⅰ型胶原染色阳性,形成钙结节,表现成骨细胞分化特点。结论在一定培养条件下成功诱导人MSCs向成骨细胞分化。在骨组织工程学方面MSCs作为种子细胞具有潜在的应用价值。     

不同代次骨髓间充质干细胞的生物学特性

间充质干细胞来源主要有骨髓,外周血,脐带脂肪组织,外周血,胎盘羊水,其他部位如胰腺、胎肝、胎肺、骨肌腱、乳汁等[1]。其具有自我更新能力、多向和定向分化能力、免疫抑制作用和趋化性、组织修复、体内移植基因治疗等作用。干细胞研究已经取得较多成果,无论在实验室还是临床研究,在使用时,干细胞代次的选择都是首先考虑的。目前国内外研究表明各代骨髓间充质干细胞其生物学特性的异同,仍无定论[2]。故专门就实验室和动物实验的     

食蟹猴心电图研究

目的 研究食蟹猴在清醒状态下的心电图特点,为食蟹猴在药物临床前安全性评价实验研究中的应用提供参考.方法 选择72只2～3岁食蟹猴,体重2.5～3.5 kg,雌雄各36只.在环境安静、动物清醒状态下,测定Ⅰ、Ⅱ、Ⅲ、aVR、aVL、aVF 6个导联的心电图变化,并计算平均心率,P波、QRS波群和T波的振幅,PR间期、QT间期等指标.结果 72只食蟹猴均为窦性心律,并发现在肢体Ⅱ导联中,P波均为向上直立波,Ⅱ、Ⅲ、aVF导联中大部分食蟹猴没有S波,aVR导联中大部分食蟹猴没有Q波.食蟹猴P波较尖,振幅较小,QRS波群多样化,QT间期的K值范围是0.302±0.040,ST段位于等电位线,T波以圆滑为主,Ⅱ导联中绝大部分为直立.结论 此研究建立了食蟹猴心电图基础数据,为相关的研究提供了参考.     

骨髓间充质干细胞治疗皮肤深度烧伤的研究进展

烧伤是由热源引起的皮肤外伤性破坏,烧伤后瘢痕的形成及汗腺的丧失等是目前临床治疗尚未解决的难题。骨髓间充质干细胞具有多向分化潜能及抗炎、分泌等生物学功能,在动物实验和临床研究中对治疗烧伤有显著疗效。     

注射用重组人成纤维细胞生长因子-21食蟹猴急性毒性试验研究

目的 观察食蟹猴单次sc注射用重组人成纤维细胞生长因子-21（RH-FGF-21）的急性毒性反应。方法 8只健康食蟹猴,随机分成RH-FGF-21组和对照组,RH-FGF-21组6只,对照组2只,均雌雄各半,分别单次sc最大给药浓度和最大给药体积的供试品RH-FGF-21（9.0 mg/kg）和最大体积的对照品灭菌注射用水（1.0 mL/kg）,给药后连续观察21 d。在给药前适应期和给药后观察期内进行动物的一般观察（外观、行为、饮食、反应能力、分泌物和排泄物等）、死亡情况、体质量变化、肛温、进食量、眼科和心电图检查、血液学和血液生化学检测、尿液观察和分析;观察期结束安乐死全部存活动物,进行组织病理学检查。结果 动物体质量、肛温、进食量、心电图检查和眼科检查与同期对照组比较均未见明显异常;血液学检测、血液生化检测、尿液观察和分析结果、组织病理学检查也未见由药物引起的异常变化。结论 在本试验条件下未发现由药物引起的急性毒性症状,9.0 mg/kg可认为是食蟹猴单次sc RH-FGF-21的最大给药量。     

Reproductive toxicity of denosumab in cynomolgus monkeys

Denosumab is a monoclonal antibody that inhibits bone resorption by targeting RANKL, an essential mediator of osteoclast formation, function, and survival. Reproductive toxicity of denosumab was assessed in cynomolgus monkeys in an embryofetal development study (dosing GD20–50) and a pre-postnatal toxicity study (dosing GD20–parturition). In the embryofetal toxicity study, denosumab did not elicit maternal toxicity, fetal harm or teratogenicity. In the pre-postnatal toxicity study, there were increased stillbirths, and one maternal death due to dystocia. There was no effect on maternal mammary gland histomorphology, lactation, or fetal growth. In infants exposed in utero, there was increased postnatal mortality, decreased body weight gain, and decreased growth/development. Denosumab-related effects in infants were present in bones and lymph nodes. There was full recovery at 6 months of age from most bone-related changes observed earlier postpartum. The effects observed in mothers and infants were consistent with the pharmacological action of denosumab.     

A multiple-dose toxicity study of tanezumab in cynomolgus monkeys

Nerve growth factor (NGF) is an important mediator of pain and hyperalgesia and has become a target of novel analgesic therapeutics. Tanezumab is a humanized IgG(2) antibody that binds NGF with high affinity and specificity. In a study to assess the toxicity and pharmacokinetic properties of tanezumab in adult, male and female, cynomolgus monkeys following weekly intravenous administration of 1, 10, or 30 mg/kg for up to 26 weeks (followed by an 8-week recovery period), tanezumab was well tolerated with no macroscopic or microscopic effects on those brain, spinal cord, nerve, or ganglia sections evaluated. One fifth of tanezumab-treated monkeys developed an antibody response to tanezumab that prevented maintenance of tanezumab exposure between dosing. In the antibody-negative animals, accumulation of tanezumab was observed; steady state was achieved approximately 8 weeks after the first dose of study drug, and exposure to tanezumab was approximately dose proportional with no observed difference between male and female animals. One monkey died during the study; this monkey had findings suggestive of hypersensitivity reaction. The favorable toxicity and pharmacokinetic profile of tanezumab seen in this study supports its further evaluation for the treatment of pain in clinical practice.     

Pharmacokinetic disposition of the novel atypical anxiolytic CGS 9896 in the cynomolgus monkey

The intravenous pharmacokinetic disposition of the novel, atypical anxiolytic CGS 9896 was studied in six cynomolgus monkeys. CGS 9896 was infused at dose levels of approximately 60, 120, and 240 cro;g/h/kg for a duration of 12 h, resulting in steady-state plasma concentrations averaging 38.4, 51.8, and 124 ng/ml, respectively. The average total systemic clearance was 35.3 ml/min/kg which was independent of dose and totally attributable to nonrenal pathways. The hepatic clearance was determined to be blood flow-rate dependent and the first-pass extraction calculated as approximately 84%. Both the apparent elimination rate constant and volume of distribution exhibited dose-dependent changes. Even though the plasma protein bound fraction was high (98.6%), no concentration dependency was observed. Furthermore, no concentration dependency was observed in the plasma/blood distribution ratio indicating the observed dose-related reduction in the volume of distribution may be attributable to nonlinear tissue uptake of CGS 9896.     

Acute toxicity test of CuO nanoparticles using human mesenchymal stem cells

Despite the growing interest in nanoparticles (NPs), standardized procedures for the evaluation of their toxicity have not been defined. The risk of human exposure is rapidly increasing and reliable toxicity test systems are urgently needed. In vitro methods are ideal in toxicology research because they can rapidly provide reproducible results while preventing the use of animals. Recently, a new test for acute toxicity based on the use of human bone marrow mesenchymal stem cells (hBMMSCs) has been developed and successfully tested in our laboratory following the Interagency Coordinating Committee on the Validation of Alternative Methods guidelines. Along these lines, the aim of this study is to evaluate the acute cytotoxicity of copper oxide (CuO) NPs using the new toxicity test based on hBMMSCs. Our results show that CuO NPs are much more toxic compared to micrometer ones. Specifically, CuO NP exposure exhibits a significant cytotoxicity at all the concentrations used, with an IC₅₀ value of 2.5?±?0.53?µg/ml. On the other hand, CuO microsized particle exposure exhibits a very low cytotoxicity at the same concentrations, with an IC₅₀ value of 72.13?±?16.2?µg/ml.     

Use of mixed-effect models and tolerance limits to evaluate control cynomolgus monkey body weight change and variability during preclinical toxicology studies

Cynomolgus monkeys are an important and widely used species in preclinical toxicology studies. During the in-life phase of study, body weight effects may be indicative of toxicity; however, trends in body weight and body weight variability are often difficult to interpret due to small sample size and/or inter- and intra-animal variability. The present analysis utilizes mixed-effect modelling, which incorporates random and fixed effects into linear regression models, to evaluate control monkey body weight trends and variability relative to baseline (initial) weight and study duration. The primary aim of this analysis is to evaluate whether mixed-effect model based tolerance limits can aide in determining whether apparent test article-related changes in body weight deviate more than the predicted variability defined by the model tolerance limits. The models for this study are based on vehicle control animal body weight data from the following studies: 1-month (20 studies, 198 animals), 3-month (19 studies, 180 animals), and 9-month (17 studies, 182 animals). The analysis presented herein provides the framework for evaluating control monkey body weight change in studies with small sample size, and anticipated control monkey body weight change relative to gender and study duration.     

Utilization of the chronic atrioventricular block cynomolgus monkey as an in vivo model to evaluate drug interaction-associated torsade de pointes

It has been difficult to experimentally reproduce synergistic effects of ketoconazole on terfenadine-induced torsade de pointes. We assessed proarrhythmic effects of terfenadine (30 mg/kg, p.o.) with/without ketoconazole (100 mg/kg, p.o.) pretreatment using the chronic atrioventricular block cynomolgus monkeys with repeated-measured design (n = 4). Terfenadine with ketoconazole pretreatment repeatedly induced non-sustained torsade de pointes in each animal, although terfenadine alone did not induce it at all. Thus, the chronic atrioventricular block cynomolgus monkeys can be used for studying drug interaction-associated torsade de pointes, providing a non-clinical strategy to circumvent untoward drug interactions in patients specially under polypharmacy.     

Developmental toxicity testing of monoclonal antibodies: An enhanced pre- and postnatal study design option

For many monoclonal antibodies (mAb), the preferred species for general and reproductive safety testing is often the cynomolgus monkey. This article describes the rationale for combining the traditional “segmented” embryofetal development study with the pre- and postnatal development (PPND) study into a single “enhanced” PPND study design in the cynomolgus monkey where a single cohort of animals is exposed throughout gestation and allowed to give birth naturally. The proposed “enhanced” PPND study design evaluates all the stages of the traditional two study design using fewer animals. It also assesses the functional consequences of mid to late gestational exposure. This is of particular relevance to the risk assessment of monoclonal antibodies where fetal exposure to maternal IgG increases as pregnancy progresses and where morphologic examination of a pre-term fetus may not be adequate to reveal the presence of adverse effects on functional development of key target organs.