Name: production of elastin-like protein hydrogels for encapsulation and immunostaining of cells in 3d
Uploaded: 2018-05-19T13:30:00
Description: Watch this Scientific Journal Video about Production of Elastin-like Protein Hydrogels for Encapsulation and Immunostaining of Cells in 3D at JoVE.com

作者感谢 t. 帕尔默和 h. (斯坦福神经外科) 提供小鼠 npc. 矢量艺术在图 4被使用了和适应了从施维雅医学艺术在创造性的共同性归属 3.0 Unported 执照 (https://creativecommons.org/许可证/3.0/legalcode)。这项工作的一部分是在斯坦福纳米共享设施 (SNSF), 在国家科学基金会的支持下, ECCS-1542152 奖。N.A.S. 承认国立卫生研究院 (32GM008412) 国立医学科学院的支持。C.M.M. 承认 NIH NRSA 博士研究生奖学金 (F31 EB020502) 和 Siebel 学者计划的支持。S.C.H. 承认国家卫生研究院 (U19 AI116484 和 R21 EB018407)、国家科学基金会 (DMR 1508006) 和加利福尼亚再生医学研究所 (RT3-07948) 提供的支持。这项研究获得了再生康复研究 & 培训联盟 (AR3T) 的资助, 该协会得到了尤尼斯肯尼迪发育研究院国家儿童健康和人类发展研究所 (国家研究所) 的支持。神经系统疾病和中风 (NINDS), 和国家生物医学成像和生物工程研究所 (NIBIB) 的国家卫生研究院的奖励号 P2CHD086843。内容完全是作者的责任, 不一定代表国家卫生研究院的意见。

1. ELP 表达式协议
<ol><li>1天: 成长的起始群体
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<li>用热处理25克 Luria 汤和15克琼脂每1升的超纯水制备氨苄西林和氯霉素琼脂板。一旦溶液冷却到摄氏60摄氏度, 加入1毫升氨苄西林 (100 毫克/毫升在超纯水) 和1毫升氯霉素库存 (34 毫克/毫升70% 乙醇) 至1升琼脂溶液的最终浓度100µg/毫升和34µg/毫升分别。用血清学吸管将20毫升最终溶液转移到10厘米培养皿中, 使琼脂凝固。包装培养皿与 par...

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	<li>Cukierman, E., Pankov, R., Stevens, D. R., Yamada, K. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Taking+Cell-Matrix+Adhesions+to+the+Third+Dimension.">Taking Cell-Matrix Adhesions to the Third Dimension.</a> Science. 294 (5547), 1708-1712 (2001).</li><li>Birgersdotter, A., Sandberg, R., Ernberg, I. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Gene+expression+perturbation+in+vitro-A+growing+case+for+three-dimensional+(3D)+culture+systems.">Gene expression perturbation in vitro-A growing case for three-dimensional (3D) culture systems.</a> Seminars in Cancer Biology. 15 (5), 405-412 (2005).</li><li>G&#243;mez-Lech&#243;n, M. 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重组蛋白的表达和纯化是制备高重现性生物材料的有力工具。由于商业化分子克隆的出现, 自定义的重组质粒可以从几个供应商购买, 这大大减少了使用 ELPs 等材料的时间。同样, 当原始的工作得到联邦合同的支持, 未来的工作将用于非营利用途时, 可以直接从原始实验室请求质粒。以前已为几个 ELP 变体31发布了完整的 ELP 氨基酸序列。然而, 从表达到最终纯化重组蛋白的过程涉及?...

在过去的一个世纪中, 二维 (2D) 组织培养已发展成为一个完整的工具集, 研究基本细胞生物学在体外。此外, 相对低成本和简单的2D 细胞培养协议导致了它在许多生物和医学学科的应用。然而, 过去的研究表明, 传统的2D 平台可能导致结果与收集的在体内明显偏离, 导致宝贵的时间和资金浪费为临床研究1,2, 3。我们和其他人推测, 这种差异可能是由于缺乏对2D 表面培养的细胞所提供的本土生物化学和生物物理线索, 这可能是对各种细胞类型的最佳增殖和成熟所必需的。
为了解决这些限制并帮助弥合 2D体外和体内研究之间的差距, 研究人员开发了三维 (3D) 水凝胶平台, 用于细胞封装14,5 ,6。水凝胶是一种理想的材料, 用于重述细胞外基质 (ECM)在体内的内源性微环境, 因为它们的组织样的机械特性和水肿胀结构, 使养分迅速运输和信号因子7,8。此外, 3D 水凝胶可设计为对脚手架的机械和生化性能有独立的控制。矩阵力学9,10,11,12和细胞胶粘剂配体13,14,15是众所周知的影响细胞行为体外和体内.因此, 3D 水凝胶具有可调谐性质, 为研究细胞与微环境的因果关系提供了平台。理想的3D 水凝胶基质的标准包括简单的, 无细胞毒性的细胞封装, 以及独立调谐生理相关的力学特性和模仿本机细胞粘附图案。
合成 (e. g, 聚乙二醇, 聚乳酸, 聚 (乙醇酸)) 和自然地 (e. g, 海藻酸盐, 胶原, 胶) 水凝胶具有超过 2D体外培养平台的优势;但是, 它们也有很大的缺点, 限制了它们的适用性。首先, 许多合成和自然衍生的平台需要苛刻的交联条件, 可能对哺乳动物细胞有潜在的毒性, 导致细胞活力降低7。此外, 许多合成平台缺乏本土生物活性, 需要通过二次化学反应进行功能化, 这可以增加成本和复杂性16。最后, 虽然自然派生的材料通常包含固有的生物活动域, 但它们往往被高批对批次的可变性所困扰, 并且通常仅限于形成相对较弱的凝胶7,17。
重组蛋白工程为材料设计提供了一个独特的工具集, 允许对蛋白质序列进行显式控制, 并通过扩展, 得到最终的水凝胶支架的潜在机械和生化特性18。此外, 通过利用众所周知的生物机械的大肠杆菌 ( 大肠杆菌) 来表达蛋白质, 材料可以生产成本效益和一贯的有限的内部和批内的变化。这里提出的弹性蛋白样蛋白质 (ELP) 有三个工程领域: (1) T7 和 His6 标签, 允许标签通过荧光标记抗体, (2) 一个 "弹性体样" 区域, 赋予弹性力学性能, 并允许化学交联, (3) 一个 ' 生物活性 ' 区域, 编码的细胞粘接图案。
我们的弹性蛋白样区域基于规范 (Val-甘-Xaa-甘)5弹性蛋白序列, 其中四 ' Xaa ' 氨基酸站点是异亮氨酸 (微笑), 但可以被设计为任何氨基酸, 除了脯氨酸。这一序列赋予了具有较低临界溶液温度 (LCST) 行为的重组 ELPs, 通过热循环19、20, 可以利用它进行简单的纯化后表达式。通过修改来宾 "Xaa" 残滓21、22, 可以将此 LCST 属性调整为在不同温度下进行热聚合。
在这里, "Xaa" 的位置上的五弹性蛋白样重复已取代了胺呈现赖氨酸 (赖氨酸) 氨基酸, 这是用于水凝胶交联。我们以前的工作表明, 与胺反应交联剂四 (羟甲基) 磷氯 (THPC)23的反应, 非细胞毒性和可靠的结合。通过改变总的蛋白质含量和交联剂浓度, 我们能够产生水凝胶, 可以调谐到跨生理相关的刚度范围 (~ 0.5-50 帕)9,23,24。除了调整机械性能外, 水凝胶内的细胞黏附力是由 ELP 蛋白的主干内的规范细胞粘附域整合而来的结果。例如, 采用扩展的纤维连接蛋白衍生的 ' RGDS ' 氨基酸序列允许细胞黏附和构象的灵活性, 而炒, 无约束力的 ' RDGS ' 变体限制细胞基质黏附力24。通过调节细胞胶粘剂与非粘附蛋白的比值以及总蛋白浓度, 我们能够有效地生产出跨越多种配体浓度的水凝胶。Resultantly, 我们开发了一个水凝胶平台, 具有分离的生物化学和生物物理性质, 可以独立调整, 以最佳的3D 文化的各种细胞类型。
除了基体刚度和胶粘剂配体调谐, 重组水凝胶提供了设计特定材料退化剖面的能力, 这对于细胞在3D 上下文中的扩散、增殖和迁移是必要的4,9. 这种退化是由蛋白酶的细胞分泌所提供的, 具体目标是扩展的 "RGDS"9或弹性蛋白样序列25。ELP 水凝胶也被证明支持后续的生化化验, 这是必要的研究细胞的生存能力和功能, 包括免疫化学和 DNA/RNA/蛋白质提取的定量逆转转录-聚合酶链反应 (qRT PCR) 和西方印迹9。ELP 变体也已在许多体内模型中使用, 并且已知免疫系统26可以很好地耐受。
结合起来, ELP 作为细胞封装研究的物质平台, 与合成或自然衍生的材料平台相比, 具有广泛的优势, 它们往往缺乏相同程度的生物化学和生物物理调谐和重复。另外, ELP 的简单和非细胞毒性使用与各种各样的细胞类型 (e. g, 小鸡背根神经节14,24, 小鼠神经祖细胞9, 人骨髓间充质干细胞27, 牛新生儿软骨细胞28, 人内皮细胞29,30) 允许与2D 细胞培养相比, 更具生理学意义的内生 3D ECM 模型。在此, 我们提出了一个协议, 以表达 recombinantly 衍生, ELPs 作为一个可调谐的水凝胶平台, 3D 细胞封装。进一步提出了包覆细胞的荧光标记和共焦显微术的方法。

<table border="0" cellpadding="0" cellspacing="0" width="904">
	<tbody>
		<tr height="21">
			<td height="21" style="height:21px;width:355px;">Elastin-Like Protein Expression and Purification</td>
			<td style="width:260px;"></td>
			<td style="width:123px;"></td>
			<td style="width:167px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">10 cm Petri Dishes</td>
			<td>Thermo Fisher Scientific</td>
			<td style="width:123px;">FB0875713</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">70% Ethanol</td>
			<td>RICCA Chemical</td>
			<td style="width:123px;">2546.70-1</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Ammonium Sulfate</td>
			<td>Sigma-Aldrich</td>
			<td style="width:123px;">A3920-500G</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Ampicillin</td>
			<td>Thermo Fisher Scientific</td>
			<td style="width:123px;">BP1760-25G</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Bacto Agar</td>
			<td>Thermo Fisher Scientific</td>
			<td style="width:123px;">9002-18-0&#160;</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">BL21(DE3)pLysS Competent Cells</td>
			<td>Invitrogen</td>
			<td style="width:123px;">C606003</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Chloramphenicol</td>
			<td style="width:260px;">Amresco</td>
			<td style="width:123px;">0230-100G&#160;</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Deoxyribonuclease I from bovine pancreas</td>
			<td>Sigma-Aldrich</td>
			<td style="width:123px;">DN25</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">EDTA disodium salt, dihydrate</td>
			<td>Thermo Fisher Scientific</td>
			<td style="width:123px;">O2793-500</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Glycerol</td>
			<td>Thermo Fisher Scientific</td>
			<td style="width:123px;">BP229-4</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Isopropanol</td>
			<td>Thermo Fisher Scientific</td>
			<td style="width:123px;">A451-4</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Isopropyl &#946;-D-1-thiogalactopyranoside (IPTG)&#160;</td>
			<td>Thermo Fisher Scientific</td>
			<td style="width:123px;">BP1755-10G</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Luria Broth</td>
			<td style="width:260px;">EMD Millipore</td>
			<td>1.10285.5007</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Parafilm</td>
			<td>VWR</td>
			<td style="width:123px;">52858-000</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Phenylmethanesulfonyl fluoride (PMSF)</td>
			<td>MP Biomedicals</td>
			<td style="width:123px;">195381</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Sodium Chloride</td>
			<td>Thermo Fisher Scientific</td>
			<td style="width:123px;">BP358-212</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Sodium Hydroxide</td>
			<td>Sigma-Aldrich</td>
			<td style="width:123px;">S 8045-1KG</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Syringe Filter Unit (0.22 &#956;m)</td>
			<td>Millipore</td>
			<td style="width:123px;">SLGP033RB</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Terrific Broth</td>
			<td style="width:260px;">Millipore</td>
			<td style="width:123px;">71754-4</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Tris Base</td>
			<td>Thermo Fisher Scientific</td>
			<td style="width:123px;">BP152-1</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Cell Encapsulation in 3D ELP Hydrogels</td>
			<td style="width:260px;"></td>
			<td style="width:123px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">0.22 &#956;m syringe filters</td>
			<td style="width:260px;">Millipore</td>
			<td style="width:123px;">SLGV004SL</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">0.5 mm thick silicone sheet</td>
			<td>Electron Microscopy Science</td>
			<td style="width:123px;">70338-05</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">24-well tissue culture plates&#160;</td>
			<td>Corning</td>
			<td style="width:123px;">353047</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Disposable Biopsy Punch (2 mm)</td>
			<td>Integra Miltex</td>
			<td style="width:123px;">33-31</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Disposable Biopsy Punch (4 mm)</td>
			<td>Integra Miltex</td>
			<td style="width:123px;">33-34</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Disposable Biopsy Punch (5 mm)</td>
			<td>Integra Miltex</td>
			<td style="width:123px;">33-35</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Dulbecco&#8217;s phosphate buffered saline (DPBS)&#160;</td>
			<td>Corning</td>
			<td style="width:123px;">21-031-CM</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:355px;">No. 1 12 mm glass coverslips</td>
			<td>Thermo Fisher Scientific</td>
			<td style="width:123px;">12-545-80</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Tetrakis(hydroxymethyl)phosphonium chloride (THPC)</td>
			<td>Sigma-Aldrich</td>
			<td style="width:123px;">404861-100ML</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">0.5% Tryspin/EDTA</td>
			<td>Thermo Fisher&#160;</td>
			<td style="width:123px;">15400054</td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:355px;">Immunocytochemistry of Cells in 3D ELP Hydrogels</td>
			<td style="width:260px;"></td>
			<td style="width:123px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">16% (w/v) Paraformaldehyde (PFA)</td>
			<td style="width:260px;">Electron Microscopy Sciences</td>
			<td style="width:123px;">15701</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Bovine Serum Albumin (BSA)</td>
			<td style="width:260px;">Roche</td>
			<td style="width:123px;">3116956001</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">DAPI (4&#39;,6-Diamidino-2-Phenylindole, Dihydrochloride)</td>
			<td>Molecular Probes</td>
			<td style="width:123px;">D1306&#160;</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Donkey Serum</td>
			<td style="width:260px;">Lampire Biological Labs</td>
			<td style="width:123px;">7332100</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Goat anti-mouse Secondary Antibody (AF488)</td>
			<td style="width:260px;">Molecular Probes</td>
			<td style="width:123px;">A-11017</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Goat anti-rabbit Secondary Antibody (AF546)</td>
			<td style="width:260px;">Molecular Probes</td>
			<td style="width:123px;">A-11071</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Goat Serum</td>
			<td>Gibco</td>
			<td style="width:123px;">16210-072</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:355px;">Mouse Nestin Primary Antibody</td>
			<td style="width:260px;">BD Pharmingen</td>
			<td style="width:123px;">556309</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Mouse Sox2 Primary Antibody</td>
			<td style="width:260px;">Cell Signaling Technology</td>
			<td style="width:123px;">23064S</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:355px;">Nail Polish</td>
			<td style="width:260px;">Electron Microscopy Sciences</td>
			<td style="width:123px;">72180</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Triton X-100</td>
			<td>Sigma-Aldrich</td>
			<td style="width:123px;">X100-100ML</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Vectashield Hardset Mounting Medium&#160;</td>
			<td style="width:260px;">Vector Labs</td>
			<td style="width:123px;">H-1400&#160;</td>
			<td></td>
		</tr>
	</tbody>
</table>

production of elastin-like protein hydrogels for encapsulation and immunostaining of cells in 3d

二维 (2D) 组织培养技术对于我们理解基本细胞生物学是必不可少的。然而, 传统的2D 组织培养系统缺乏三维 (3D) 矩阵, 导致在收集的体外和体内中的结果之间存在显著的脱节。为了解决这一限制, 研究人员设计了3D 水凝胶组织培养平台, 可以模拟体内细胞微环境的生物化学和生物物理特性。这项研究促使需要开发支持3D 细胞封装和下游生化检测的材料平台。重组蛋白工程为3D 水凝胶材料的设计和开发提供了独特的工具集, 允许对蛋白质序列进行特定的控制, 因此, 通过推广, 其潜在的机械和生化性质的结果矩阵。在这里, 我们提出了一个协议, 以表达 recombinantly 衍生弹性体样蛋白 (ELP), 它可以用来形成水凝胶具有独立可调谐的机械性能和细胞粘附物的浓度。我们进一步提出了 ELP 水凝胶内的细胞封装方法, 以及随后的嵌入细胞的免疫荧光染色, 用于下游分析和定量。

此协议中使用的 ELPs 包括五区域: T7 标记、His6 标记、肠激酶 (克朗) 解切站点、生物活动区域和弹性蛋白样区域 (图1)。T7 和 His6 标签允许通过标准的西方印迹技术容易识别。如果需要的话, 引入克朗解理的地方允许酶去除标记区域。生物活性区域编码的扩展, 纤维连接蛋白衍生细胞胶粘剂 (' RGDS ') 或非胶粘剂 (' RDGS ') 序列。最后, 类似弹性蛋白的区域?...

Watch this Scientific Journal Video about Production of Elastin-like Protein Hydrogels for Encapsulation and Immunostaining of Cells in 3D at JoVE.com

Production of Elastin-like Protein Hydrogels for Encapsulation and Immunostaining of Cells in 3D

重组蛋白工程水凝胶有利于3D 细胞培养, 因为它们允许完整的调谐的聚合物骨干, 因此, 细胞微环境。在这里, 我们描述了重组弹力蛋白样蛋白质纯化的过程及其在3D 水凝胶细胞封装中的应用。

3D 染色细胞的包覆和超弹性蛋白样凝胶的制备

Two-dimensional (2D) tissue culture techniques have been essential for our understanding of fundamental cell biology. However, traditional 2D tissue ...

Research

JoVE Journal

Bioengineering

Ordering Single Cells and Single Embryos in 3D Confinement: A New Device for High Content Screening

订货单细胞和单胚胎的三维约束：高内涵筛选新设备

Biological cells are usually observed on flat (2D) surfaces. This condition is not physiological, and phenotypes and shapes are highly variable. Screening ...

科研

生物工程

Production, Characterization and Potential Uses of a 3D Tissue-engineered Human Esophageal Mucosal Model

三维组织工程人食管黏膜型号生产，表征和潜在用途

The incidence of both esophageal adenocarcinoma and its precursor, Barrett&#8217;s Metaplasia, are rising rapidly in the western world. Furthermore ...

Tunable Hydrogels from Pulmonary Extracellular Matrix for 3D Cell Culture

可调水凝胶由肺细胞外基质的三维细胞培养

Here we present a method for establishing multiple component cell culture hydrogels for in vitro lung cell culture. Beginning with healthy en bloc lung ...

Improved 3D Hydrogel Cultures of Primary Glial Cells for In Vitro Modelling of Neuroinflammation

Improved 3D Hydrogel Cultures of Primary Glial Cells for In Vitro Modelling of Neuroinflammation

改良的3D 水凝胶培养的原发胶质细胞的体外Neuroinflammation 模型的建立

In the central nervous system, numerous acute injuries and neurodegenerative disorders, as well as implanted devices or biomaterials engineered to enhance ...

Flash NanoPrecipitation for the Encapsulation of Hydrophobic and Hydrophilic Compounds in Polymeric Nanoparticles

闪速纳米沉淀法包聚物纳米粒子中疏水亲水化合物的作用

The formulation of a therapeutic compound into nanoparticles (NPs) can impart unique properties. For poorly water-soluble drugs, NP formulations can ...

Measuring Global Cellular Matrix Metalloproteinase and Metabolic Activity in 3D Hydrogels

三维水凝胶中全球细胞基质金属蛋白酶和代谢活性的测定

Three-dimensional (3D) cell culture systems often more closely recapitulate in vivo cellular responses and functions than traditional two-dimensional (2D) ...

Controlled Strain of 3D Hydrogels under Live Microscopy Imaging

实时显微镜成像下的 3D 水凝胶控制应变

External forces are an important factor in tissue formation, development, and maintenance. The effects of these forces are often studied using specialized ...

Light-Controlled Fermentations for Microbial Chemical and Protein Production

用于微生物化学和蛋白质生产的光控发酵

Microbial cell factories offer a sustainable alternative for producing chemicals and recombinant proteins from renewable feedstocks. However, ...

Large-Scale, Automated Production of Adipose-Derived Stem Cell Spheroids for 3D Bioprinting

Adipose-derived stromal/stem cells (ASCs) are a subpopulation of cells found in the stromal vascular fraction of human subcutaneous adipose tissue ...

Fragmenting Bulk Hydrogels and Processing into Granular Hydrogels for Biomedical Applications

破碎散装水凝胶并加工成颗粒状水凝胶，用于生物医学应用

Granular hydrogels are jammed assemblies of hydrogel microparticles (i.e., &#34;microgels&#34;). In the field of biomaterials, granular hydrogels have ...