碱性成纤维细胞生长因子和表皮生长因子联合诱导骨髓基质细胞分化形成神经球

目的观察碱性成纤维细胞生长因子(bFGF)和表皮生长因子(EGF)联合诱导骨髓基质细胞(MSCs)能否分化形成神经球。方法采用全骨髓法培养MSCs,bFGF和EGF联合诱导MSCs,倒置显微镜下观察分化细胞的形态,免疫荧光法和免疫印迹法鉴定分化细胞。结果 bFGF和EGF联合应用,可有效地诱导MSCs形成神经球。此神经球能传代并分化成神经元样细胞。免疫荧光和免疫印迹法均证实神经球表达nestin蛋白,神经球分化的细胞表达神经元、胶质细胞和少突胶质细胞标志性蛋白。结论 bFGF和EGF联合应用,可有效地诱导MSCs形成神经球。此神经球能自我更新并分化为神经元、胶质细胞和少突胶质细胞。     

胶原-壳聚糖/bFGF培养人成纤维细胞生物特性研究

目的：研究一种适于人成纤雏细胞生长的组织工程支架材料，确定碱性成纤维细胞生长因子(bFGF)的用量。材料与方法：采用胶原与壳聚糖整合bFGF做为人成纤维细胞生长的支架材料，用体外细胞培养法确定胶原与壳聚糖在材料中的配比，用体外细胞相容性直观法观察材料与人成纤维细胞的相容性。结果：选择出了胶原与壳聚糖在材料中较佳的配比，确定了bFGF在材料中的用量范围．人成纤维细胞在胶碌一壳聚糖／bFGF膜持续生长繁殖，具有生物降解性。材料与细胞呈低毒性反应。结论：胶原—壳聚糖／bFGF可做为组织工程的支架材料。     

碱性成纤维细胞生长因子对瘢痕成纤维细胞生物学行为的影响

目的探讨碱性成纤维细胞生长因子（bFGF）对瘢痕成纤维细胞生物学特性的影响。方法采用细胞培养、MTT、ELISA法、氯胺T和RT—PCR法检测bFGF在不同作用剂量下对瘢痕来源的成纤维细胞生长增殖和细胞外基质（ECM）合成的影响。结果（1）MTT检测bFGF对瘢痕成纤维细胞有明确的促增殖作用，并具有剂量相关性；（2）氯胺T法显示实验组和对照组HPr含量无显著性差异，RT—PCR法显示各组Ⅰ、Ⅲ型胶原蛋白mRNA表达水平无明显变化；说明bFGF对瘢痕成纤维细胞胶原蛋白的合成无促进作用；（3）ELISA法表明随着bFGF作用浓度的升高，FN的表达表现为增高趋势，且以100ng／ml浓度下作用最显著。结论bFGF可以促进创面愈合，但不引起瘢痕的过度形成。     

羧甲基壳聚糖、盐酸氨基葡萄糖及N-乙酰氨基葡萄糖对大鼠胰岛细胞生长及胰岛素分泌量的影响

通过胶原酶消化法获得大鼠胰岛单层细胞 ,并用转板以及碘乙酸处理的方法除去其中的成纤维细胞 ,得到比较纯的胰岛内分泌细胞 ,以此为材料研究了羧甲基壳聚糖、盐酸氨基葡萄糖、N 乙酰氨基葡萄糖对大鼠胰岛细胞生长和胰岛素释放的影响。实验结果表明 ,羧甲基壳聚糖、盐酸氨基葡萄糖、N 乙酰氨基葡萄糖均能够促进大鼠胰岛细胞的生长。采用放射免疫法测定培养的胰岛细胞分泌胰岛素含量 ,结果表明 ,羧甲基壳聚糖具有刺激大鼠胰岛细胞胰岛素释放的作用。     

人表皮细胞分离培养最佳条件的选择

目的 确定表皮细胞分离培养的最佳条件，为进一步将其作为皮肤组织工程种子细胞奠定基础。方法 采用组织块法培养表皮细胞；分别以胰蛋白酶和分散酶分离表皮细胞，有血清培养法和无血清培养法进行表皮细胞的培养，并以克隆形成试验检测细胞存活和生长情况。结果 （1）表皮细胞以分散分离可量在多数基底细胞，且成纤维细胞污染少，而胰蛋白酶得到的表皮细胞少，且混杂有大量的成纤维细胞。（2）组织块法可观察到表皮细胞生长，但成纤维细胞污染严重，且不易得到成片生长的表皮。（3）有血清培养法表皮细胞需在3T3细胞的滋养层上生长，存在3T3细胞污染的可能。（4）无血清培养方法简便易行，更有利于表皮细胞的生长。结论 采用无血清培养法培养表皮细胞条件的最终确定，为进行相关的研究，尤其是皮肤组织工程的研究奠定了基础。     

利用载有角质细胞生长因子微囊的组织工程皮肤修复裸鼠皮肤缺损

背景：组织工程皮肤作为一项新兴技术拥有良好的应用前景。有研究表明,角质细胞生长因子可以促进表皮细胞增殖。 目的：观察荷载角质细胞生长因子纳米微囊的新型组织工程皮肤修复裸鼠皮肤缺损的效果和特点。 方法：构建荷载角质细胞生长因子的脱细胞真皮基质复合物;将人表皮干细胞群和成纤维细胞分离、培养,并且进行鉴定;将表皮干细胞群接种于复合物之上,观察其生长状况;将荷载角质细胞生长因子纳米微囊的组织工程皮肤移植于裸鼠皮肤缺损处,将无角质细胞生长因子纳米微囊的组织工程皮肤作为空白组,将其自体皮肤移植修复缺损组作为对照组,于移植后2,4,6周时观察皮片挛缩及组织学愈合情况,并应用抗人角蛋白10及β1-整合素免疫荧光检测修复区表皮和真皮层细胞来源、分化及生长情况。 结果与结论：表皮干细胞在复合物表面生长良好,黏贴紧密,可见有连接成片趋势的小圆形的表皮干细胞及多角形的终末表皮细胞,部分形成克隆团块。移植后第2,4,6周,荷载角质细胞生长因子纳米微囊组织工程皮肤修复裸鼠皮肤缺损的结果均优于空白组及对照组,移植的皮肤边缘与邻近皮肤完全融合,但存在一定程度的挛缩。修复区组织工程皮肤的表皮细胞分层良好并能产生角质层,同时,移植后8,10周,组织工程皮肤切片免疫荧光染色可以鉴别出少量β1-整合素阳性细胞,均为表皮干细胞或短暂扩充细胞。结果证实,荷载角质细胞生长因子纳米胶囊的新型组织工程皮肤修复裸鼠皮肤缺损的效果较好,优于普通组织工程皮肤及自体全厚皮片移植修复。 中国组织工程研究杂志出版内容重点：组织构建;骨细胞;软骨细胞;细胞培养;成纤维细胞;血管内皮细胞;骨质疏松;组织工程     

骨髓基质细胞体外诱导分化成神经元和胶质细胞

目的　探索骨髓基质细胞 (bonemarrowstromalcells,BMSC)体外诱导分化为神经元和神经胶质细胞的可行性 ,为BMSC在神经科学领域内的应用奠定基础。方法　以成年犬BMSC为实验对象 ,利用碱性成纤维细胞生长因子 (bFGF)、表皮生长因子 (EGF)、维甲酸 (RA)、脑源性神经营养因子 (BDNF)、胶质细胞系来源神经营养因子 (GDNF)等作为增殖及分化诱导因子 ,进行增殖培养、分化诱导 ;免疫组化法进行细胞性质鉴定。结果　加入bFGF、EGF增殖培养 72h可见细胞分裂相 (成纤维细胞样细胞 )。加入RA、BDNF、GDNF诱导 3d ,部分细胞有NSE、GFAP成分表达 ;第 10d可见有神经元、神经胶质形态样细胞形成 ,经细胞成分 (NSE、GFAP)鉴定证实为神经元、神经胶质细胞。结论　BMSC在体外培养条件下 ,经过bFGF、EGF、RA、BDNF、GDNF等因子的“程序性”作用 ,可以分化成神经元和神经胶质细胞     

表皮细胞生长因子对角质形成细胞体外增殖作用的研究

目的：观察重组人表皮生长因（Recombinant human epidermal growth factor,rhEGF）对人角质形成细胞的细胞周期以及促切口愈合作用。方法：运用包皮环切术后收集培养角质细胞,不同浓度的重组人表皮细胞生长因子处理细胞,MTT法、↑3HtdR掺入法测细胞生长率;流式细胞仪检测细胞周期。结果：体外实验表明5～100ng·ml^-1重组人表皮细胞生长因子可促进人角质形成细胞生长,其中浓度为10ng·ml^-1促进细胞生长作用最为显著。流式细胞仪检测10ng·ml^-1重组人表皮细胞生长因子处理后细胞增殖明显,S和G2／M期细胞数明显增加。结论：重组人表皮细胞生长因子可促进细胞生长。     

308nm准分子激光对人角质形成细胞活力及bFGF表达与分泌的影响

目的:探讨308 nm准分子激光对人角质形成细胞(hKCs)活力及碱性成纤维细胞生长因子(bF-GF)表达与分泌的影响。方法:体外培养人角质形成细胞,免疫荧光法鉴定细胞。分别予不同剂量308 nm准分子激光及311 nm窄谱中波紫外线(NB-UVB)照射,MTT法检测hKCs细胞活力,RT-PCR法和ELISA法分别检测bFGF表达和分泌水平,并与NB-UVB进行对比。结果:细胞鉴定证实为角质形成细胞。308 nm准分子激光剂量达600 mj/cm2,NB-UVB剂量达500 mj/cm2时hKCs活力下降;2种光源在一定剂量范围内照射均可使hKCs表达、分泌bFGF水平增加,并呈剂量依赖性;308 nm准分子激光诱导hKCs分泌bFGF的水平高于NB-UVB。结论:308 nm准分子激光照射对hKCs活力的影响小于NB-UVB;308 nm准分子激光可以通过剂量依赖的方式诱导hKCs表达与分泌bFGF来促使白癜风复色,与NB-UVB相比效果更佳。     

成年小鼠背部皮肤角质形成细胞的原代培养及其与乳鼠角质形成细胞的对比性研究

目的:探索成年小鼠背部皮肤角质形成细胞有效且高生长率的原代培养方法;对比乳鼠和成年小鼠背部皮肤角质形成细胞的增殖、集落形成效率与凋亡能力。方法:取正常成年小鼠背部皮肤,分别利用4种方法分离其表皮与真皮,取表皮分离培养角质形成细胞;免疫荧光进行细胞鉴定;调整种板密度、种板方式观察细胞生长状况;利用CCK-8、EdU、结晶紫染色法和TUNEL染色检测乳鼠与成年小鼠背部皮肤角质形成细胞的增殖、集落形成效率与凋亡情况。结果:4种成年小鼠表皮-真皮分离方式中,二步消化法获得的细胞量最大、细胞增殖能力最强、集落形成效率高;水滴状种板法较普通平铺种板法集落形成率高;乳鼠角质形成细胞最适种板密度约为3.2×10^4/cm^2,成年小鼠背部皮肤角质形成细胞最适种板密度约为1.6×10^4/cm^2;与成年小鼠背部皮肤角质形成细胞相比,乳鼠角质形成细胞增殖能力较强、集落形成效率较高。结论:成功建立了较为完善的成年小鼠背部皮肤角质形成细胞原代培养体系。     

Effect of EGF and bFGF on Fibroblast Proliferation and Angiogenic Cytokine Production from Cultured Dermal Substitutes

Abstract

Growth factors accelerate wound healing but the underlying mechanisms remain poorly understood. The aim of this study was to investigate the effect of epidermal growth factor (EGF) and basic fibroblast growth factor (bFGF) on fibroblast proliferation and production of angiogenic factors from cultured dermal substitutes (CDS). In the first experiment, fibroblasts were seeded into a flask at a density of 1 × 10⁴ cells/cm².Cell proliferation was assessed after culturing in media containing EGF or bFGF at concentrations ranging from 2 to 50 μg. The number of fibroblasts increased significantly in the presence of EGF or bFGF, but fibroblasts detached from the flasks in the presence of 50 μg bFGF. In the second experiment, CDS were prepared by incorporating fibroblasts into collagen gels. To make a wound surface model, the CDS was elevated to the air–liquid interface, on which a spongy sheet of hyaluronic acid (HA) containing EGF or bFGF was placed. The amount of vascular endothelial growth factor (VEGF) and hepatocyte growth factor (HGF) released from the CDS after 1 week of cultivation was measured by ELISA. When the CDS was covered with a HA sponge containing EGF (Group 1), fibroblasts released 3.5-times more VEGF compared with a HA-alone sponge (control group). When covered with a HA sponge containing bFGF (Group 2), 8.7-times more VEGF was released compared with the control group. Fibroblasts in Groups 1 and 2 released 9.6- and 9.3-times more HGF, respectively, compared with the control group. Thus, EGF stimulates fibroblasts to produce VEGF and HGF, in addition to its ability to enhance epidermal cell proliferation.     

rhIL-17A对人皮肤角质形成细胞和成纤维细胞活性和凋亡的影响

目的: 研究重组人白细胞介素17A (rhIL-17A)对人角质形成细胞和成纤维细胞活性、凋亡及成纤维细胞促纤维化因子分泌的影响,探讨IL-17在系统性硬皮病发病中的作用。方法: 用不同浓度的rhIL-17A作用于角质形成细胞和成纤维细胞,CCK-8测定其对角质形成细胞和成纤维细胞活性的影响;Western blotting 检测核转录因子NF-κB/p65及其抑制性蛋白IκBα的表达量;流式细胞术观察细胞凋亡变化;ELISA 检测rhIL-17A 处理组和对照组成纤维细胞培养液上清中IL-6和TGF-β₁的含量。结果: rhIL-17A处理组和对照组角质形成细胞活性没有明显差别;rhIL-17A 处理组成纤维细胞活性较对照组明显升高(P<0.05),rhIL-17A 处理组成纤维细胞NF-κB/p65表达量增加,而IκBα表达量降低;rhIL-17A 对2种细胞凋亡率无明显影响;rhIL-17A 处理组成纤维细胞IL-6 和TGF-β₁分泌量增加。结论: rhIL-17A对体外培养人角质形成细胞的活性没有明显影响,却可以显著增强体外成纤维细胞的活性,IL-17A对成纤维细胞活性增强的这种促进作用,可能是通过激活NF-κB实现。rhIL-17A可能通过刺激成纤维细胞分泌IL-6 和TGF-β₁,从而进一步引起成纤维细胞增殖和胶原合成。IL-17可能参与了系统性硬皮病的发病过程。     

Chromosome abnormalities of porokeratosis-cultured epidermal keratinocytes. Comparison with those of cultured dermal fibroblasts.

Cultured epidermal keratinocytes and dermal fibroblasts derived from porokeratosis (PK) patients' skin lesions or normal-appearing skin had numerical and sometimes structural chromosomal abnormalities. Such abnormal cells were seen in 4.08% and 0.375% of all the studied epidermal keratinocytes derived from affected skin and normal-appearing skin, respectively. Similar abnormalities were present in 1.70% and 3.67% of the dermal fibroblasts from the patients' affected skin and normal-appearing skin, respectively. Chromosomal abnormalities were more frequent in keratinocytes and fibroblasts from the patients' skin than in keratinocytes (0.429%) or in fibroblasts (1.22%) derived from normal control donors. Clonal proliferation of such abnormal cells was frequently seen in keratinocytes from the patients' affected skin. The frequent appearance of chromosomal abnormalities and clonal proliferation in epidermal keratinocytes may explain skin lesion formation and skin cancer development in PK patients.     

The effect of carboxymethyl-chitosan on proliferation and collagen secretion of normal and keloid skin fibroblasts

In this study, different molecular weight CM-chitosans were prepared and the effects on the growth and collagen secretion of normal skin fibroblasts and keloid fibroblasts were investigated in vitro. CM-chitosan promoted the proliferation of the normal skin fibroblast significantly but inhibited the proliferation of keloid fibroblast. The higher CM-chitosan concentration had a higher initial effect and the lower CM-chitosan concentration had a longer affecting time to the normal skin fibroblast. The lower molecular weight CM-chitosan had significant twofold activities. The CM-chitosan could reduce the ratio of type I/III collagen in keloid fibroblast by inhibiting the secretion of collagen type I; and had no effect on the secretion of types I and III collagen in the normal skin fibroblast.     

人羊膜匀浆上清液对大鼠角朊细胞生长的影响

目的观察不同浓度人羊膜匀浆上清液(hAHS)对体外培养的SD大鼠角朊细胞生长的影响。 方法取SD大鼠背部皮肤,采用中性蛋白酶与胰蛋白酶复合消化的方法,分离第一代角朊细胞。将新鲜人羊膜制备成hAHS,采用考马斯亮蓝法、酶联免疫吸附试验分别测定hAHS中总蛋白含量和表皮生长因子(EGF)、碱性成纤维生长因子(bFGF)、血管内皮生长因子(VEGF)的浓度。用不同浓度hAHS对第一代角朊细胞进行体外培养：将细胞以2.5×10⁴个/mL密度接种于96孔板中(每孔100 μL),随机数字表法将其分为体积分数0(对照组)及10%、15%、20%、25% hAHS组,用含10%胎牛血清低糖培养基培养24 h后,根据hAHS在低糖DMEM培养基中的不同体积分数进行换液,分别于培养即刻和培养24、48、96 h,用噻唑兰法检测各孔的吸光度值并绘制角朊细胞的生长曲线和计算各组细胞增殖率。采用SPSS13.0统计软件进行分析,各不同体积分数hAHS组的数据与对照组比较采用Dunnett－t检验。 结果hAHS中总蛋白含量为(675.435±9.215)×10^－3 g/L,EGF、bFGF和VEGF的浓度分别为(470.625±2.546)×10^－6、(4.121±0.026)×10^－6和(0.172±0.002)×10^－6 g/L。与对照组比较,10% hAHS组培养48、96 h角朊细胞增殖率明显高于对照组,差异均有显著性统计学意义(t＝4.644、9.694,P值均小于0.01),15% hAHS组培养48、96 h角朊细胞增殖率均明显高于对照组,差异均有显著性统计学意义(t＝4.766、6.648,P值均小于0.01);20% hAHS组培养24 h角朊细胞增殖率高于对照组,差异有统计学意义(t＝2.272,P<0.05),培养48、96 h增殖率均明显高于对照组,差异有显著性统计学意义(t＝5.027、8.861,P值均小于0.01);25% hAHS组培养48 h增殖率低于对照组,差异有统计学意义(t＝2.188,P<0.05),培养96 h增殖率明显低于对照组,差异有显著性统计学意义(t＝5.147,P<0.01)。 结论体积分数10%、15%、20% hAHS对体外培养的角朊细胞增殖有明显促进作用,且促增殖的效果随hAHS体积分数的增加而增强,但hAHS的体积分数在25%时角朊细胞的增殖受到抑制,平稳期相对缩短。     

Development of bFGF-Chitosan Matrices and Their Interactions with Human Dermal Fibroblast Cells

Chitosan (CH) is a naturally derived, biodegradable polymer of glucosamine with a variable frequency of N-acetyl-D-glucosamine units, and has been demonstrated to have numerous pharmacological and wound-healing properties. Biodegradable chitosan films were fabricated using a solvent casting technique and investigated for skin tissue-engineering applications. Basic fibroblast growth factor (bFGF) was incorporated into the CH matrices (1 μg/film) by 3 methods: adsorption, entrapment and covalent binding. Release rates and biological activity of the incorporated bFGF were monitored. Human dermal fibroblasts (HDF cells) were used as an in vitro model for cell response to CH and bFGF-CH films. Cell attachment, growth and acid-soluble collagen quantification were employed as an assessment of cell function. The fibroblasts were found to remain viable on the chitosan films and scaffolds. CH films without bFGF were compatible with HDF cells; however, the fibroblasts did not proliferate. The release profile of adsorbed and bound bFGF from CH films were similar (indicating that binding was not efficient) while entrapped bFGF was not released in the time frame studied. The concentration of bFGF released to the cell culture medium was not high enough to stimulate HDF proliferation. However, cell attachment was significantly increased in chitosan films with bFGF adsorbed onto the surface as compared to control surfaces. HDF cells grown on CH films produced significantly more collagen than those on control surfaces.     

Immunohistochemical expression of growth factors in subacute thyroiditis and their effects on thyroid folliculogenesis and angiogenesis in collagen gel matrix culture

The inflammatory-mechanistic basis of subacute thyroiditis remains unclear. To elucidate the roles of vascular endothelial cell growth factor (VEGF), basic fibroblast growth factor (bFGF), platelet-derived growth factor-BB (PDGF), transforming growth factor-β1 (TGF-β1) and epidermal growth factor (EGF) in the inflammatory process, their immunoexpression was examined in biopsy specimens of ten cases. At the granulomatous stage, all cases expressed VEGF, bFGF, PDGF, and TGF-β1 in monocytes/macrophages infiltrating into follicle lumina, and in both epithelioid histiocytes and multinucleated giant cells of the granulomas. In fibroblasts and endothelial cells around the granulomas, all cases displayed VEGF, bFGF, and PDGF, but TGF-β1 was detected only in fibroblasts in two cases. No cases expressed EGF in any of the above cell types. At the regenerative stage, all cases expressed VEGF, bFGF, and EGF in regenerating thyrocytes, whereas three and no cases displayed PDGF and TGF-β1, respectively. Ten, seven and six cases expressed PDGF in fibroblasts, endothelial cells, and monocytes, respectively. In these cell types, all cases expressed VEGF and bFGF, whereas no cases displayed TGF-β1 and EGF. To estimate the roles of these growth factors in thyroid tissue regeneration, their effects on thyroid folliculogenesis and angiogenesis were examined using collagen gel culture of thyrocytes and endothelial cells, respectively. Cell proliferation was also studied by bromodeoxyuridine (BrdU) uptake. EGF decreased follicle formation and TGF-β1 drastically inhibited it, but the others had no effect. VEGF showed the greatest effect on vessel formation, although all of the others promoted it. EGF and VEGF or bFGF caused the highest BrdU uptake in thyrocytes and endothelial cells, respectively. The data suggest firstly, that at the granulomatous stage of subacute thyroiditis, growth factor-rich monocytes/macrophages infiltrating into follicle lumina trigger the granulomatous reaction, and VEGF, bFGF, PDGF, and TGF-β1 produced by the stromal cell types tested mediate the reaction; secondly, that at the regenerative stage, EGF serves follicle regeneration through its mitogenic effect on thyrocytes, although some cofactors with EGF are involved in folliculogenesis and the decreased expression of TGF-β1, a fibrogenic factor, contributes to thyroid tissue repair; and thirdly, that VEGF and bFGF are more responsible for the angiogenesis at both stages than the other factors studied. Copyright © 1999 John Wiley & Sons, Ltd.     

A bilayer scaffold prepared from collagen and carboxymethyl cellulose for skin tissue engineering applications

Abstract

Treatment of chronic skin wound such as diabetic ulcers, burns, pressure wounds are challenging problems in the medical area. The aim of this study was to design a bilayer skin equivalent mimicking the natural one to be used as a tissue engineered skin graft for use in the treatments of problematic wounds, and also as a model to be used in research related to skin, such as determination of the efficacy of transdermal bioactive agents on skin cells and treatment of acute skin damages that require immediate response. In this study, the top two layers of the skin were mimicked by producing a multilayer construct combining two different porous polymeric scaffolds: as the dermis layer a sodium carboxymethyl cellulose (NaCMC) hydrogel on which fibroblasts were added, and as the epidermis layer collagen (Coll) or chondroitin sulfate-incorporated collagen (CollCS) on which keratinocytes were added. The bilayer construct was designed to allow cross-talk between the two cell populations in the subsequent layers and achieves paracrine signalling. It had interconnected porosity, high water content, appropriate stability and elastic moduli. Expression of vascular endothelial growth factor (VEGF), basic-fibroblast growth factor (bFGF) and Interleukin 8 (IL-8), and the production of collagen I, collagen III, laminin and transglutaminase supported the attachment and proliferation of cells on both layers of the construct. Attachment and proliferation of fibroblasts on NaCMC were lower compared to performance of keratinocyte on collagen where keratinocytes created a dense and a stratified layer similar to epidermis. The resulting constructs succesfully mimicked in vitro the natural skin tissue. They are promising as grafts for use in the treatment of deep wounds and also as models for the study of the efficacy of bioactive agents on the skin.