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1.
Objective: Animal environments for the growth of stem cells cause the transmission of some diseases and immune problems for the recipient. Accordingly, replacing these environments with healthy environments, at least with human resources, is essential.  One of the media that can be used as an alternative to animal serums is Wharton acellular jelly (AWJ).  Therefore, in this study, we intend to replace FBS with Wharton jelly and investigate its effect on the expression of megakaryocyte-related genes and markers in stem cells. Materials and Methods: In this study, cord blood-derived CD34 positive HSCs were cultured and expanded in the presence of cytokines including SCF, TPO, and FLT3-L. Then, the culture of expanded CD34 positive HSCs was performed in two groups: 1) IMDM culture medium containing 10% FBS and 100 ng / ml thrombopoietin cytokine 2) IMDM culture medium containing 10% AWJ, 100 ng / ml thrombopoietin cytokine.  Finally, CD41 expressing cells were analyzed with the flow cytometry method. The genes related to megakaryocyte lineage including FLI1 and GATA2 were also evaluated using the RT-PCR technique.  Results: The expression of CD41, a specific marker of megakaryocyte lineage in culture medium containing Wharton acellular jelly was increased compared to the FBS group. Additionally, the expression of GATA2 and FLI1 genes was significantly increased related to the control group. Conclusion: This study provided evidence of differentiation of CD34 positive hematopoietic stem cells from umbilical cord blood to megakaryocytes in a culture medium containing AWJ.  相似文献   
2.
Aim of the workTo assess urinary soluble CD163 (sCD136) in systemic lupus erythematosus (SLE) patients compared to healthy controls. In addition to determine its association with different SLE clinical features, laboratory investigations and pathological indices focusing on those suggest renal disease activity.Patients and methodsThe study included 58 SLE patients and 30 controls. SLE disease activity index (SLEDAI) was assessed and patients subdivided into active lupus nephritis (ALN) (renal SLEDAI ≥ 4) and no-renal activity (NRA) SLE patients (renal SLEDAI = 0). Urinary sCD163 was measured by Enzyme-Linked Immunosorbent Assay (ELISA). Urine values were normalized to urinary creatinine excretion. Renal biopsies were performed in 21 ALN patients.ResultsThey were 54 females and 4 males with a mean age 31.8 ± 9.1 years and disease duration 6.2 ± 4.8 years. They were 31 with ALN and 27 NRA SLE patients. Urinary sCD163 level was significantly higher in SLE patients (1.85 ± 0.3) than controls (0.5 ± 0.36, p < 0.001). In ALN, it was significantly higher (2.91 ± 2.52) compared to NRA SLE patients (0.64 ± 0.38) and controls (p < 0.001 in both). The optimum cut-off value above which normalized urinary sCD136 can predict renal activity was > 0.82 with sensitivity of 90.3%, specificity of 88.89%, p < 0.001. Urinary sCD163 significantly correlated with renal (r = 0.75, p < 0.001) but not with extra-renal SLEDAI. It correlated with activity index of renal biopsy (r = 0.46, p = 0.038).ConclusionUrinary sCD163 is a potential biomarker for LN activity. Its level is associated with clinical features, laboratory investigations and pathological indices that indicate renal disease activity.  相似文献   
3.
目的:探讨天然CD25和FOXP3抗体在非小细胞肺癌(NSCLC)患者血浆表达变化的临床意义及其作为诊断标志物的潜能。方法:选取青岛大学附属青岛市立医院胸外科首次确诊且未经任何治疗的NSCLC患者200例及同期性别、年龄、吸烟史相匹配的健康志愿者190例,收集两组血液样本。基于CD25及FOXP3分子结构,利用表位预测软件(http://www.iedb.org)设计并合成3条线性抗原肽(即CD25a、CD25b、FOXP3)并外送化工公司合成,通过自行建立的优化ELISA检测方法,检测NSCLC患者及健康对照组血浆CD25及FOXP3抗体的表达水平,并分析CD25及FOXP3抗体的表达与临床病理特征之间的关系。同时绘制ROC曲线,评估CD25及FOXP3抗体对不同TNM分期NSCLC的诊断价值。结果:NSCLCⅡ~Ⅳ期患者血浆CD25a、FOXP3抗体的表达较健康对照组显著增加(0.66±0.18 vs 0.52±0.17,P<0.001;0.60±0.23 vs 0.53±0.25,P<0.001),NSCLC患者血浆CD25b抗体的表达较健康对照显著降低,这一变化在Ⅰ...  相似文献   
4.
目的探讨白细胞介素37b重组蛋白(rmIL-37b)通过调节CD39/ATP轴抑制树突状细胞(DC)诱导类风湿性关节炎(RA)大鼠炎症反应的机制。方法将SD大鼠随机分为空白对照组(CTL)、CIA模型组、rmIL-37b 5μg/kg组、rmIL-37b 10μg/kg组,每组各10只。除了空白对照组外,其余大鼠采用含有卡介苗的完全弗氏佐剂和牛Ⅱ型胶原混合乳液免疫刺激,建立CIA模型。确定建模成功当天(D0),rmIL-37b组分别尾静脉注射5μg/kg、10μg/kg rmIL-37b;CTL组和CIA模型组注射相同体积的(1 ml/kg)生理盐水,连续给药15 d。免疫组化法检测滑膜组织Nod样受体蛋白3(NRPL3)炎症小体的表达,流式细胞术检测DC表型,另外试剂盒检测血清三磷酸腺苷(ATP)和免疫学指标。结果与CIA模型组相比,rmIL-37b 10μg/kg组大鼠足容积、AI值、NLRP3炎症小体表达量、血清ATP、IL-1β、IL-18、肿瘤坏死因子α(TNF-α)、抗Ⅱ型胶原抗体亚型(anti-ColⅡ-IgG、anti-ColⅡ-IgG2a)水平均降低,同时DC表面CD...  相似文献   
5.
目的 探讨 CD73 对大鼠心肌细胞(CMs)增殖和功能的影响。 方法 体外培养原代大鼠 CMs 和大鼠心肌细胞系 H9C2,构建慢病毒 CD73 过表达载体和空载病毒组,分别转染 CMs 和 H9C2。实验分组:CD73 过表达组(OE组)和阴性对照组(NC组),即CMs-OE组和CMs-NC组;H9C2-OE组和H9C2-NC组,每组各5只。Real-time PCR 法检测转染病毒后各组细胞 CD73 基因水平表达情况;MTT 法检测细胞增殖能力变化;无损伤心肌细胞功能分析仪检测 CMs 细胞增殖曲线、倍增时间和搏动变化。 结果 慢病毒转染 CMs 和 H9C2 72 h 后,过表达组 CD73 mRNA 水平明显高于对照组(P<0.05);CMs和 H9C2 转染后3~4 d的增殖能力为OE组大于NC组(P<0.05);CMs 和 H9C2 细胞增殖曲线均显示 OE 组高于 NC 组,CMs 和 H9C2 倍增时间为 OE 组低于 NC 组(P<0.05);CMs转染后72 h显示OE组细胞搏动率高于NC组, OE组转录因子T-同源盒基因5(TBX5)表达和血管内皮生长因子(VEGF)的分泌高于NC组,而缺氧诱导因子1α(HIF-1α)及肝病坏死因子α(TNF-α)的分泌低于NC组。 结论 CD73可促进 CMs 和 H9C2 的增殖,促进 CMs 搏动及TBX5表达和VEGF分泌,抑制HIF-α和TNF-α的分泌。  相似文献   
6.
BackgroundPlatelet transfusion therapy is widely used to prevent hemorrhage in patients with thrombocytopenia and platelet disorders. The platelet concentrate (PC) quality is affected by increased storage time, as reflected in the decreased number of platelets, morphological changes, and impaired functions. This study aimed to analyze the impact of 5 days storage on platelets count and the expression of CD63, and Annexin V as activation markers during PC storage.MethodsFifty PCs collected from single donors were tested for platelet count on days 0, 3, and 5 using a Sysmex blood counter. CD61, CD63, and Annexin V expression was analyzed by a multicolor Navios flow cytometer.ResultsThere was a significant decrease in platelet count during 5 days of storage. There was a direct relationship between storage time and degree of platelet activation. CD63 had almost double increased expression on day 5 than day 3. Annexin V showed significantly increased expression on day 3 with minor differences between days 3 and 5.ConclusionAccording to standard blood bank conditions, PC stored for 5 days showed a degree of in vitro activation as evidenced by CD63 and Annexin V expression, may lead to reduced therapeutic efficacy. Flow cytometry monitoring platelet activation in PC offers a better understanding of the changes during PC storage and may help improve platelet products.  相似文献   
7.
目的 探讨免疫球蛋白κJ区的重组信号结合蛋白(RBP-Jκ)对CD133阳性室管膜细胞增殖与分化的影响及可能的机制。 方法 分离孕12 d的美国癌症研究所(ICR)胚胎小鼠(3只)侧脑室室管膜细胞进行原代培养,并使用RBP-Jκ-siRNA干扰RBP-Jκ,以及选用2~3月龄体重为20~25 g的CD133-CreERTM::ROSA26-LacZ::RBP-Jκflox/flox小鼠(3只),通过腹腔注射他莫昔芬(TAM)敲除RBP-Jκ,通过免疫荧光双标染色检测CD133阳性室管膜细胞的增殖和分化变化的情况,最后通过Real-time PCR、Western blotting检测RBP-Jκ及其上下游相关分子表达情况。 结果 干扰或敲除RBP-Jκ后,无论是细胞还是动物水平CD133或β-半乳糖苷酶(β-GAL)/双肾上腺皮质激素(DCX)/β-微管蛋白Ⅲ(β-tubulinⅢ)、CD133或β-GAL/微管相关蛋白2(MAP-2)或神经元核抗原(NeuN)、CD133或β-GAL/增殖细胞核抗原(PCNA)双阳性细胞数目均明显增加。同时Real-time PCR和Western blotting结果表明,在干扰或敲除RBP-Jκ后RBP-Jκ-和Splity多毛增强子1(Hes1)mRNA及蛋白表达量均显著下降,而Notch1 mRNA及蛋白的表达量反而显著增加。 结论 干扰或敲除RBP-Jκ,通过Notch1表达上调、Hes1表达下调,最终引起CD133阳性室管膜细胞的增殖与分化增加。  相似文献   
8.
9.
In the field of drug development, technology for producing human metabolites at a low cost is required. In this study, we explored the possibility of using prokaryotic water-soluble cytochrome P450 (CYP) to produce human metabolites. Streptomyces griseolus CYP105A1 metabolizes various non-steroidal anti-inflammatory drugs (NSAIDs), including diclofenac, mefenamic acid, flufenamic acid, tolfenamic acid, meclofenamic acid, and ibuprofen. CYP105A1 showed 4′-hydroxylation activity towards diclofenac, mefenamic acid, flufenamic acid, tolfenamic acid, and meclofenamic acid. It should be noted that this reaction specificity was similar to that of human CYP2C9. In the case of mefenamic acid, another metabolite, 3′-hydroxymethyl mefenamic acid, was detected as a major metabolite. Substitution of Arg at position 73 with Ala in CYP105A1 dramatically reduced the hydroxylation activity toward diclofenac, flufenamic acid, and ibuprofen, indicating that Arg73 is essential for the hydroxylation of these substrates. In contrast, substitution of Arg84 with Ala remarkably increased the hydroxylation activity towards diclofenac, mefenamic acid, and flufenamic acid. Recombinant Rhodococcus erythrocyte cells expressing the CYP105A1 variant R84A/M239A showed complete conversion of diclofenac into 4′-hydroxydiclofenac. These results suggest the usefulness of recombinant R. erythropolis cells expressing actinomycete CYP, such as CYP105A1, for the production of human drug metabolites.  相似文献   
10.
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