三維微重力細(xì)胞組織培養(yǎng)系統(tǒng)
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世界唯一、模擬體內(nèi)環(huán)境、三維微重力細(xì)胞組織培養(yǎng)系統(tǒng)的原理
(詳情請見 http://www.equl.com)
【重大意義】
組織移植:例如RCCS培養(yǎng)的肝和自然的在整體上無區(qū)別,使局部組織移植成為可能。
疫苗生產(chǎn):以前丙肝疫苗效果不佳的原因之一是用來產(chǎn)生這種疫苗的病毒并不長在人的肝臟中, 現(xiàn)在RCCS培養(yǎng)的肝使產(chǎn)生肝炎疫苗的病毒生長在人的肝臟成為現(xiàn)實。RCCS在美國已廣泛用于生產(chǎn)。
軟骨再生:經(jīng)培養(yǎng)的軟骨密度極高,可治療關(guān)節(jié)損傷。
激素、酶和其它由人體組織產(chǎn)生的蛋白以及基因工程:經(jīng)培養(yǎng)的高分化的人體組織,其被刺激后能分泌治療用的蛋白。例如經(jīng)培養(yǎng)的神經(jīng)組織產(chǎn)生的神經(jīng)生長激素能修復(fù)脊椎的損傷。
骨髓再生:培養(yǎng)的骨髓生長情況極佳,且可連續(xù)進(jìn)行增生和低溫冷凍保藏,可建大型骨髓庫。
糖尿。阂葝u素培養(yǎng)后能插入體內(nèi)繼續(xù)生長,無數(shù)患者有望免去長期注射胰島素。
有效殺滅腫瘤:對腫瘤組織活體取樣,與自身的白細(xì)胞或淋巴細(xì)胞在RCCS中混合培養(yǎng),刺激或馴化它們來識別和攻擊腫瘤組織,然后把經(jīng)馴化后有殺傷力的細(xì)胞直接注入病灶。這樣,這些經(jīng)感化的淋巴細(xì)胞徹底殺滅了腫瘤。
腫瘤、愛滋病、腎病和心臟病的理想模型:培養(yǎng)人的器官、腺體和淋巴結(jié)。然后感染這些類器官,再跟蹤其生長。把藥物用在被感染的經(jīng)培養(yǎng)的組織模型上,研究其對抗疾病的效果及其對抗方式。例如腫瘤組織的培養(yǎng)有利于測試化療藥在病人自身的經(jīng)培養(yǎng)和分化的腫瘤上的療效,避免了用藥的盲目性。以前這是在鼠的組織模型上進(jìn)行的,但物種差異使許多腫瘤在鼠中的生長情況并不好。而在RCCS中,所有的腫瘤組織都完好生長,且避免了原先鼠蛋白的干擾。
皮膚移植:經(jīng)培養(yǎng)的皮膚具有極高分化度避免了以前培養(yǎng)的皮膚在肌理、靈巧度和膚色的不足。
【超前優(yōu)勢】
RCCS具有普通培養(yǎng)裝置無可比擬的三大特點。
1.高分化度:
RCCS使高分化的人體組織能在實驗室中生長,模仿感興趣的器官和腫瘤。
2.模擬微重力:
以前要在體外模擬正常組織的微環(huán)境因細(xì)胞外基質(zhì)太復(fù)雜和難適應(yīng)環(huán)境而受阻,而細(xì)胞外基質(zhì)對于調(diào)節(jié)細(xì)胞骨架和細(xì)胞核基質(zhì)蛋白非常重要。RCCS使分裂原本應(yīng)在一起的細(xì)胞組織成分的重力問題得到解決。
3.三維細(xì)胞培養(yǎng):
而普通生物反應(yīng)器因要保持細(xì)胞的懸浮而產(chǎn)生剪切力。其破壞了細(xì)胞間和細(xì)胞與基質(zhì)間的穩(wěn)定,使組織和細(xì)胞集中于自身的修復(fù), 而大大影響其生長和其它的正常生理功能。發(fā)酵罐主要培養(yǎng)大量細(xì)菌, 不適于大量培養(yǎng)人及其它哺乳動物細(xì)胞組織,因很難把大量的細(xì)胞移植到發(fā)酵罐中,即使能夠培養(yǎng), 所得的細(xì)胞數(shù)也有限且很難生成組織。而RCCS行且可用于大規(guī)模生產(chǎn),其細(xì)胞的成活率平均為97%且分化度極高。
【系統(tǒng)特點】
RCCS圓柱狀的培養(yǎng)容器中充滿了用作培養(yǎng)基的生長液以及細(xì)胞或組織材料。整個容器由電機驅(qū)動沿水平軸旋轉(zhuǎn)。細(xì)胞顆粒在水平軸內(nèi)建立均質(zhì)的液體懸浮軌道。培養(yǎng)基以及細(xì)胞顆粒隨容器一起旋轉(zhuǎn)且不與容器壁和它物相撞。由于系統(tǒng)無推進(jìn)器、空氣升液器、氣泡或攪拌器,使破壞性應(yīng)力減到最小。RCCS中的細(xì)胞通過膜式氣體交換器來吸氧和排出CO2。任何氣泡都被清除,以防其旋渦對細(xì)胞的生長的影響。無破壞應(yīng)力使生成的三維組織具有與父系相同的結(jié)構(gòu)和功能。其組織的培養(yǎng)密度為10E10至10E11個細(xì)胞/ml;細(xì)胞的培養(yǎng)密度為10E8。至今所有的細(xì)胞組織都能培養(yǎng)。全球含中國已有2千多臺。
CHARATERISTICS OF DIFFERENT BIOREACTORS
Sheer Stress Mass Transfer Dimensionality Co-location of Dissimilar Cell Types Cell Density Static Culture System (T-Flasks) None Adequate 2D 3-4 layers 2D Limited 0.3-1x10^6 cells/ml Static Matrix Cultures None Limited 3D Limited 3D Limited Low Roller Bottles Medium Good 2D 3-4 layers 2D Very Limited 1-5x10^6 cells/ml Stirred Suspension Culture Medium/High Good Very Limited 3D Very Limited 10^6-10^7 cells/ml
Airlift Bioreactors Medium/Low Good Very Limited 3D Very Limited 10^6-10^8 cells/ml Hollow Fiber Perfused Systems None Good Limited 3D Limited 10^7-10^8 cells/ml RCCS Very Low Excellent Excellent 3D Excellent 10^7-10^8 cells/ml
美國宇航局(NASA)約翰遜航天中心(JSC)的生物技術(shù)計劃目前涉及到被重力所限制的或者能在微重力中被改良的生物技術(shù)的研究領(lǐng)域,包括細(xì)胞培養(yǎng)、細(xì)胞分離、細(xì)胞融合和生物聚合。
多虧美國的載人航天計劃,科學(xué)家能較長時間地進(jìn)入空間這個的獨特的研究環(huán)境。但是現(xiàn)在,在JSC生物技術(shù)實驗室的科學(xué)家已經(jīng)發(fā)明了一系列出色的能在地球上模擬微重力的部分特征的細(xì)胞培養(yǎng)系統(tǒng)。
作為細(xì)胞科學(xué)家,也許你知道重力對您的研究所帶來的影響。重力使我們在試管內(nèi)培養(yǎng)細(xì)胞達(dá)不到如同在體內(nèi)一樣的效果。由于氣體擴散,營養(yǎng)物的有效性和代謝廢物的排除都是有限的,故在平的培養(yǎng)板上的細(xì)胞通常僅局限于進(jìn)行2維生長。在這種受限的環(huán)境中,細(xì)胞即使能聚集成團(tuán),這個團(tuán)狀物通常過小,以至于不適合用來進(jìn)行較理想的研究。
克服這些重力所致的限制的嘗試使得各種包括攪動培養(yǎng)物的系統(tǒng)和那些細(xì)胞流動著的培養(yǎng)液從細(xì)胞間穿過的系統(tǒng)。即使這些系統(tǒng)已能進(jìn)行高密度的生長,3維組織生長受限的問題依然存在。
例如在一些傳統(tǒng)的生物反應(yīng)器中,細(xì)胞被推進(jìn)到容器的上部,從而暫時地戰(zhàn)勝了重力。但是,重力的這個恒定的向下拉力最終得勝,使細(xì)胞沉到容器的更動蕩的區(qū)域。在這個有湍流和流體動態(tài)的剪刀力的區(qū)域中,原來在容器較穩(wěn)定區(qū)域所形成的細(xì)胞聚集體被分裂。另外,與生物反應(yīng)器的碰撞同樣也會使細(xì)胞遭受某種程度的損傷。
任何克服重力所致的限制的暫時的勝利都必須權(quán)衡是否損傷細(xì)胞和分裂細(xì)胞聚合體。但是,在微重力為基礎(chǔ)的研究環(huán)境中,這種情況并不存在。
在微重力環(huán)境中,無沉降和密度不均所致的對流現(xiàn)象。原先在重力環(huán)境下,不同的密度的粒子因重力作用而沉降,但在微重力中,他們卻能維持在懸浮狀態(tài)。因為許多這些重力所致的對于培養(yǎng)的限制因素能在微重力中被克服。
在JSC被發(fā)明和生產(chǎn)的旋轉(zhuǎn)式的組織培養(yǎng)容器能通過沿水平軸向旋轉(zhuǎn)培養(yǎng)液、細(xì)胞和容器壁來模擬微重力的某些特征。
結(jié)果是這個低流動剪切的培養(yǎng)環(huán)境促進(jìn)了細(xì)胞與細(xì)胞間的相互作用,并且增加了細(xì)胞的自由度以形成如細(xì)胞團(tuán)狀的三維組織。
這種容器也促進(jìn)了氣體和培養(yǎng)液的最理想的擴散,以及廢物的最佳排放以得到高密度的細(xì)胞和組織培養(yǎng)的產(chǎn)物。
另外一個好處是其具不同的沉降率的細(xì)胞能進(jìn)行共同培養(yǎng)和相互作用,以至形成如在這個共同培養(yǎng)實驗中所見的3維聚集物。
在Synthecon的旋轉(zhuǎn)式細(xì)胞培養(yǎng)容器中,象這樣的3維聚集物是正常的。故這種特性的3維聚集物經(jīng)常與細(xì)胞的因子的產(chǎn)生和細(xì)胞的分化聯(lián)系起來。
Synthecon目前有4種特有的培養(yǎng)系統(tǒng):
1. 慢速轉(zhuǎn)動的單端固定的容器或STLV是一種批量培養(yǎng)的容器
2. 原先在設(shè)計上用來進(jìn)行灌注培養(yǎng)和貼壁細(xì)胞培養(yǎng)的灌注培養(yǎng)系統(tǒng)
3. 原先在設(shè)計上用來進(jìn)行貼壁和懸浮培養(yǎng)的高截面縱橫比或HARV容器
4. 通過復(fù)雜的過程控制式計算機來控制組織培養(yǎng)系統(tǒng)的空間生物反應(yīng)器。
空間反應(yīng)器能對活體細(xì)胞培養(yǎng)條件的參數(shù)進(jìn)行實時控制,如溫度、pH平衡、營養(yǎng)物、廢液以及對低剪刀力細(xì)胞懸浮體進(jìn)行實時控制。空間生物反應(yīng)器是在設(shè)計上用于微重力的獨特的研究工具。當(dāng)航天飛機回到在地球上后,生物反應(yīng)器因能模擬部分微重力的特征,從而使得在空間微重力環(huán)境中形成的脆的3維的細(xì)胞聚集物得以保護(hù)。
空間生物反應(yīng)器在宇宙站與航天飛機和生物技術(shù)設(shè)施有很好的兼容性。所有這些容器都是建筑在通過沿水平軸旋轉(zhuǎn)來減少重力因素的基礎(chǔ)上的。
美國宇航局(NASA)的旋轉(zhuǎn)式組織培養(yǎng)容器是具劃時代意義的在地面上從事的研究的裝置,她把微重力的優(yōu)勢帶到地面實驗室中來。
但是,這些優(yōu)勢并不僅局限于實驗室范圍內(nèi),通過模擬在太空中的微重力環(huán)境,這些培養(yǎng)系統(tǒng)是從事以下研究的獨特的工具:
1. 低剪刀力
2. 不同大小顆粒的共同培養(yǎng)
3. 有助于3維組織的形成
4. 有助于細(xì)胞的分化
憑借其生長和維持聚集物那樣的活組織的能力,細(xì)胞和組織科學(xué)家有條件對新生和外植細(xì)胞的生長和相互作用的基本過程進(jìn)行研究。
在微重力環(huán)境下所進(jìn)行的長期的細(xì)胞培養(yǎng),使得我們能對生物過程進(jìn)行更深層次的研究,并且,也為醫(yī)學(xué)和產(chǎn)業(yè)的應(yīng)用打開了大門。
The Rotary Cell Culture System (RCCS) from Synthecon is a new development in bioreactor technology which enables the cultivation of differentiated three dimensional cultures that mimic the structure and function of parental tissues.
Developed at the Johnson Space Center at NASA, the RCCS was originally designed to protect the delicate tissue cultures during space flight. However, it quickly became apparent that the unique environment provided by the RCCS of low shear force, high mass transfer and microgravity, enables three dimensional cell growth to take place in a conventional tissue culture incubator.
APPLICATIONS
The RCCS has a wide range of cell and clinical, research applications including cancer research, "In Vitro" toxicology testing and tissue engineering.
CANCER RESEARCH
Research and phase I clinical trials are already underway using the RCCS to investigate the growth and malignant changes of cancers as they develop from single cells to tumors including Melanoma, Prostate cancer, Breast cancer, Ovarian cancer, Osteosarcoma, Glioma, and Colon cancers. The RCCS model of three dimensional cell culture will enable the examination of gene expression as a function of the stage of tumor cell aggregate growth. This data may be useful in refining molecular-based approaches for the identification of genetic makers for patient prognosis, and in the design of specific molecular therapies.
Applications of Rotary Cell Culture
Research
Cancer
HIV
Tissue Modeling
Virus Vector
Tissue Regeneration
Bone Marrow
Liver
Pancreas
Skin
Heart Valve
Nerve
Cartilage
Kidney
Blood
Blood Vessels
Production
Monoclonal Antibodies
Polypeptides from Transformed Insect Cells
Proteins, Pharmaceuticals
Undiscovered Proteins from Differentiated Cultures
IN VITRO TOXICOLOGY
Evidence suggests that the "configuration" of cell cultures influences their metabolic behavior towards different compounds, potentially masking or enhancing a pharmacologic or toxic effect. For example human hepatocytes grown as monolayer cultures metabolise the analgesic drug mofezolac at a significantly higher rate than cell suspension cultures. The differentiated three dimensional tissue produced in the RCCS provides a model which resembles the structure and function of parental tissue more closely than any other "In Vitro'''''''' culture system currently available.
CARTILAGE AND BONE TISSUE CULTURE
Considerable effort is being made to research methods for regenerating and repairing bone and cartilage. Several techniques, including bone implants and grafts are showing promise for providing a remedy for skeletal disorders and chondrodystrophies. The RCCS creates a culture environment conducive to cell aggregation, and provides a powerful new tool for the study of bone formation and chondronic mutations.
LIVER CULTURE
The RCCS provides a means to grow and expand hepatocyte culture into high fidelity models of liver tissue. This will have a number of important applications including the design of gene therapy protocols, hepatocyte transplantation, the development of extracorporal assist devices, and test systems for the design of hepatitis vaccines and testing of antiviral compounds.
THE PRINCIPLE OF CELL CULTURE
Most culture systems address one specific parameter e.g. shear force, at the expense of others i.e. mass transfer of nutrients and metabolic wastes, three dimensionality, and/or co-cultivation of dissimilar cell types. The RCCS is the first bioreactor designed to simultaneously integrate co-cultivation, low shear, high mass transfer, and three dimensional growth without sacrificing any other parameter.
The RCCS is a zero head space, aqueous medium filled bioreactor that suspends particles by rotating the vessel wall and integral gas diffusion membrane around the horizontal axis. This rotation can hold particles of up to 1 cm in diameter in orbital suspension, as the sedimentation forces induced by gravity are balanced by the centrifugal force generated by the rotation of the vessel.
Non-adherent cells may be cultured in suspension while adherent cells are grown on microcarriers. Long term cultures of weeks to several months can be maintained with appropriate media changes.
Cell Types Grown in the Rotary Cell Culture System
Anchorage Dependant
Normal Human Keratinocytes
Primary human embryonic kidney
Human neuroblastoma
Human breast cancer
Human prostate cancer
Human lung cancer
Human melanoma
Human kidney cancer
Normal small intestine (epithelial & fibroblasts)
Human skin fibroblasts
Melanocytes
Primary rat osteoblasts
Mouse osteoblast cell line
Rat salivary gland fibroblasts
BHK-21
Suspension Cultures
Human lymphocytes
Primary normal human hepatocytes
Primary mouse bone marrow stem cells
SP2 (mouse myeloma fusion partner)
L-1210 Leukemic cells of mice
Mouse hybridoma cell lines
Pancreatic tissue
Plant cells (tobacco callus)
Sf9 insect cells
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