精制原代地鼠肾细胞狂犬病疫苗灭活工艺的改进

为了提高精制原代地鼠肾细胞狂犬病疫苗（ＰＰＨＫＲＶ）的质量,在甲醛浓度,温度和时间相同的条件下,对静置法和转瓶法灭活狂犬病毒后制成的疫苗进行了效力测定比较,结果表明采用转瓶灭活的ＰＰＨＫＲＶ效力高于静置灭活法。     

应用细胞工厂建立人用狂犬病疫苗连续培养多次收获工艺

目的为提高生产效率、增加原代地鼠肾细胞单产量及狂犬病病毒产量,建立人用狂犬病疫苗（地鼠肾细胞）连续培养多次收获工艺。方法选用12-14日龄SPF地鼠,无菌取肾经消化,制备成细胞悬液,分装到40层细胞工厂并培养细胞成单层;接种狂犬病病毒固定毒aG株,连续培养病毒并多次收获。分别对同一细胞批制备的多个单次病毒收获液的免疫原性、病毒滴度和地鼠肾细胞蛋白质含量进行检测。结果用40层细胞工厂培养原代地鼠肾细胞和狂犬病病毒,细胞接种浓度为1．0×10。～1．5x10。cells／mL,（36±1）℃培养72h成致密单层;按0．1MOI病毒接种,可进行6次收获病毒;多个单次病毒收获液病毒滴度均不低于6．0lgLD50／mL;免疫原性检查保护指数不低于100;地鼠肾细胞蛋白质残留量随着收获次数的增加而不断降低。结论用细胞工厂建立了人用狂犬病疫苗连续培养多次收获工艺,能显著提高地鼠。肾单产量,增加产能。     

牛肾细胞在两种不同载体中培养效果的比较

目的通过牛肾细胞在两种不同载体中培养效果的比较,为牛肾细胞在细胞工厂中规模化生产提供真实的、有力的支持。方法不同代次牛肾细胞在两种载体中经过相同培养条件进行培养。结果实验中原代牛肾细胞在细胞工厂接种密度为5.5×104/cm2左右,在15 L转瓶接种密度为9.0×104/cm2左右。一代牛肾细胞在细胞工厂接种密度为6.5×104/cm2左右,在15 L转瓶接种密度为10×104/cm2左右。二代牛肾细胞在细胞工厂接种密度为7.0×104/cm2左右,在15 L转瓶接种密度为14×104/cm2左右。两种载体中牛肾细胞生长状况均能达到培养要求。结论细胞工厂能在有限的空间内利用最大限度的培养表面培养牛肾细胞,不仅节约了传代前的细胞用量,而且提高了培养后的细胞产量。     

细胞工厂生产口服轮状病毒活疫苗的应用研究

为了确定用细胞工厂生产口服轮状病毒活疫苗的工艺参数和质控点,将原代牛肾细胞按20×104个/cm2接种到细胞工厂培养,待形成良好单层后按4×104个/cm2连续传代2次后接种轮状病毒,并与转瓶作对照.结果显示,用细胞工厂生产口服轮状病毒活疫苗与转瓶培养无差异,细胞工厂可用于改进口服轮状病毒活疫苗的生产.     

微载体规模化培养细胞的研究

通过实验探索使用微载体进行动物细胞规模化培养,以期达到建立规模化生产病毒疫苗的目的。实验研究了Vero细胞的生长曲线,以及对细胞生长过程中影响细胞生长的葡萄糖、氨含量两个主要因素的变化规律以及微载体浓度与细胞密度的关系。通过实验发现微载体规模化培养细胞易于操作,比传统转瓶培养的细胞密度高,封闭式的培养方式不但减少了污染几率,而且可以充分保证疫苗的质量。最终找出适宜疫苗培养的微载体使用浓度为2.5g/L,适宜的细胞接种浓度为:1~5×105cell/m l。     

细胞工厂培养轮状病毒基因重配株Ls(G3型)条件的优化研究

目的以细胞工厂代替转瓶培养轮状病毒基因重配株Ls的可行性研究。方法采用细胞工厂与相应的转瓶培养工艺作对比,比较两种容器内细胞生长状态与病毒收获液滴度,并对细胞工厂培养条件进行了优化。结果以相同浓度接种细胞时,细胞工厂4 d长成单层,转瓶却需要7 d,经细胞仪计数后单位面积内细胞密度相当;以相同MOI接种病毒后,转瓶内的病毒于第7天病毒滴度达到峰值,细胞已完全脱落;细胞工厂于第3天病毒滴度达到峰值,并实现了3次收获。细胞工厂每次收获的病毒液滴度都稳定在一定范围,与转瓶相当。另外,细胞工厂培养条件优化结果表明,Vero细胞最佳接种浓度为3.0×104细胞/cm2,接种病毒的最适MOI为0.02~0.04。结论使用细胞工厂培养Ls株病毒不仅提高了效率,而且减少了培养空间,可替代转瓶规模化生产轮状病毒疫苗。     

培养条件对狂犬病毒宿主细胞质量的影响

在原代地鼠肾细胞组织培养的狂犬病疫苗 (ＰＨＫＣＶ)工业化生产中 ,组织培养细胞的质量 (细胞是否贴壁 ,贴壁时间长短 ,细胞形态的保持 ,细胞老化的快慢 )以及数量 (细胞贴壁的多少 ,细胞脱落程度等 )是ＰＨＫＣＶ各步生产的基础 ,是疫苗效力的决定因素[1] 。本文对消化液中胰蛋白酶浓度、培养液小牛血清质量、维持液的成分与细胞质量的关系进行了观察和比较。现将实验报告如下。1　材料与方法1 1　材料1 1 1　培养材料 :37℃恒温 ,转瓶式培养的原代地鼠肾细胞 ,采用自繁自养 2周龄 ( 1 2日～ 1 4日龄 ) ,体重 1 2～ 1 4ｇ健康仔鼠肾…     

细胞工厂在轮状病毒基因重配株LD9培养中的应用初探

为了探索用细胞工厂代替转瓶培养轮状病毒基因重配株LD9及收获高滴度的LD9病毒原液和提高产量的可行性,分别在2层4、层细胞工厂和3L1、5L转瓶培养Vero细胞,比较两种容器内细胞的生长状态。结果显示,以相同活细胞数2.5×104/ml同时接种两种不同培养容器时,细胞工厂培养3d已长成单层,而转瓶培养需5d;对两种容器长满单层时的细胞经胰酶消化后通过细胞仪计数、分析,结果显示,两种容器培养细胞长成单层时的单位面积细胞密度相当;对长成致密单层细胞的两种容器以相同的MOI(MOI=0.1)接种LD9病毒,转瓶培养的病毒于第8d病毒滴度达到高峰,为6.0～6.5 lgCCID50/ml;细胞工厂第5d病毒滴度达高峰,为6.5 lgCCID50/ml,并于第9d病毒滴度再次达到峰值,为6.0～6.5 lgCCID50/ml,实现二次收获病毒。     

地鼠肾细胞培养的CTN株狂犬病新疫苗研究

应用细胞毒种代替豚鼠脑毒种制备狂犬病地鼠肾细胞纯化疫苗。将狂犬病毒CTN株在原代地鼠肾细胞（PHKC）传代适应,用病毒培养液上清作为生产用毒种,结果通过在PHKC传10多代,适应后病毒滴度达到了7.0LogLD50/ml,并应用适应株（CTN－LS－HK）细胞毒种制备三批疫苗,其效力在6.11-6.55IU/ml,高于用aG株豚鼠脑毒种制备的三批疫苗效力（3.77-5.85IU/ml)。     

鸡胚细胞的微载体培养

国外有许多利用微载体培养各种贴壁细胞的报道。鸡胚细胞(CEF cells)是最早用于体外培养的细胞之一,用它可生产多种鸡的疫苗,如法氏囊、新城疫、马立克疫苗等。我国生产上多采用滚瓶法,近年来才有微载体法培养的探索。要进行细胞的大规模培养,转瓶是有效的模拟,可以模拟生物反应器培养的一些条件,为放大作准备。本文模拟生物反应器的培养条件,用500ml转瓶（装液200ml）研究了鸡胚细胞在徽栽体上巾壁和生长的规律,为放大培养作了准备。     

Cell growth optimization in microcarrier culture

Three monkey kidney cell lines and primary chicken embryo cells were grown in microcarrier culture. The carrier support was DEAE-Sephandex gel beads at low anion exchange capacity prepared according to a protocol developed at the Massachusetts Institute of Technology. The growth rate of the cells and the final cell density in microcarrier culture was dependent on the concentration of the beads in culture and on the size of the initial cell inoculum. A bead concentration of 1.0 to 2.0 mg of beads/ml of tissue culture medium and a cell inoculum of 20,000 cells/cm2 of bead surface appeared to be optimal. The efficiency of the microcarrier culture system was compared to that of stationary and roller bottle cultures. Stationary flasks gave cell densities about twofold higher than maximal densities in roller bottles and about threefold and twofold higher than cell densities in microcarrier culture at a bead concentration of 2.5 and 1.0 mg/ml, respectively. In terms of cell yield per milliliter of tissue culture medium, the microcarrier culture was superior to roller bottle and stationary cultures. An advantage of the microcarrier culture system is its suitability for scale up into large volume production units.     

Cell growth optimization in microcarrier culture

Summary Three monkey kidney cell lines and primary chicken embryo cells were grown in microcarrier culture. The carrier support was DEAE-Sephadex gel beads at low anion exchange capacity prepared according to a protocol developed at the Massachusetts Institute of Technology. The growth rate of the cells and the final cell density in microcarrier culture was dependent on the concentration of the beads in culture and on the size of the initial cell inoculum. A bead concentration of 1.0 to 2.0 mg of beads/ml of tissue culture medium and a cell inoculum of 20,000 cells/cm² of bead surface appeared to be optimal. The efficiency of the microcarrier culture system was compared to that of stationary and roller bottle cultures. Stationary flasks gave cell densities about twofold higher than maximal densities in roller bottles and about threefold and twofold higher than cell densities in microcarrier culture at a bead concentration of 2.5 and 1.0 mg/ml, respectively. In terms of cell yield per millitier of tissue culture medium, the microcarrier culture was superior to roller bottle and stationary cultures. An advantage of the microcarrier culture system is its suitability for a scale up into large volume production units.     

Production of high titre disabled infectious single cycle (DISC) HSV from a microcarrier culture

Disabled Infectious Single Cycle (DISC) HSV-2 has been cultured in the complimentary cell line CR2 to provide high titre bulk material suitable for the purification of the virus as a live viral vaccine. CR2 cells are cultured on the microcarrier Cytodex-1 at 5 g l-1 in small scale (1 l) and larger scale (15 l) reactors. The cells are infected at an MOI of 0.01 pfu cell-1 and the culture harvested 60–72 h later. The infected cells are removed from the microcarriers by the addition of a hypotonic saline and the virus released by low-pressure disruption techniques. Virus titres achieved are compared to the standard roller bottle process. The resulting material is the starting point for the purification of the DISC-HSV virus. This revised version was published online in July 2006 with corrections to the Cover Date.     

中试制备临床级别第三代慢病毒

基因治疗是一个快速发展的领域,其中关于慢病毒介导的外源基因导入研究得最为广泛。随着研发技术的不断发展,在安全性方面慢病毒已经从第一代发展至第三代,而如何工程化获得高滴度慢病毒仍是当今技术一大瓶颈。运用Fibra-Cel片状载体作为HEK293T细胞载体基质,联合多个无菌细胞转瓶在滚瓶机上培养,对贴壁细胞进行规模放大化生产。通过对第三代慢病毒包装过程中影响慢病毒滴度的因素进行逐一筛选,使病毒滴度达到最优。研究结果成功运用Fibra-Cel片状载体作为HEK293T细胞粘附载体基质,作为一种贴壁细胞规模放大的方法,筛选出了利用滚瓶机制备第三代慢病毒的最优条件,规模化生产了3批慢病毒。在时间上,将慢病毒的生产时间从质粒转染到病毒收集的120 h缩短至54 h;在成本上,利用滚瓶机代替生物反应器实现了无需反复灭菌、全程一次性产品的安全有效低成本的运行,为慢病毒的规模化制备提供了技术上的支持,为临床应用奠定了坚实的基础。     

Comparisons of microcarrier cell culture processes in one hundred mini-liter spinner flask and fifteen-liter bioreactor cultures

Microcarrier cell culture process can be used to culture anchorange-dependent cells in large bioreactor vessels. The process performance in large bioreactors is usually less prominent than that in spinner flask vessels and bench scale reactors. In this study we investigated the microcarrier cell culture processes in 100?ml spinner flask and 15-liter bioreactor cultures, including the kinetics for cell attachment, cell growth and the production of Japanese encephaltilis vaccine strain (Beijing-1) virus. Under a fixed concentration of microcarrier and cell density used in inoculations, the attachment kinetics of Vero cells on Cytodex 1 microcarrier in a 15-liter bioreactor vessel was 2 folds slower than with 100?ml spinner flask culture. Virus replication in 15-liter bioreactor culture also revealed an approximately one day lag-time compared to 100?ml spinner flask culture. Findings presented herein provide valuable information for designing and operating microcarrier cell culture processes in large bioreactor vessels.     

Method for the passaging of microcarrier cultures to a production scale for producing high titre Disabled Infectious Single Cycle-Herpes Simplex Virus Type-2

A complementary cell line CR2 is currently used to propagate the Disabled Infectious Single Cycle Herpes Simplex Virus Type 2 (DISC HSV-2) on a small laboratory scale upto 15 L. These cultures are initiated by passaging the cells from roller bottle cultures. Whilst this is suitable for the laboratory scale it is totally impractical for use in seeding an industrial manufacturing scaled version of the culture. It is paramount to have a robust system for passaging cells from a small microcarrier culture system to a larger one by a serial subculturing regime. Here we report on the successes we have had in our laboratory in scaling up our production system for the DISC HSV-2 from small 1-L cultures to a 50-L vessel with the maintenance of the viral productivity. Ease of use, reproducibility and the need to minimise overall production times were factors which were taken into consideration whilst developing our procedures. We were aware of the need to keep a production train simple and as short as possible as this was the small scale study for an envisaged manfacturing process.     

Large scale production and purification of human retrovirus-like particles related to the mouse mammary tumor virus

Abstract Human retrovirus-like particles related to mouse mammary tumor virus (MMTV) are secreted in a steroid-dependent manner by the breast cancer cell line T47D. We report the successful large scale production and purification of these particles from culture supernatants of T47D cells and describe the experimental conditions established for this purpose. Thus, mg amounts of particles were produced by large scale culturing of T47D cells in an autoharvesting roller bottle system and purified by differential centrifugation and continuous flow ultracentrifugation on density gradients with a 50% recovery and a 350-fold enrichment.     

Evaluation of the new serum-free medium (MDSS2) for the production of different biologicals: Use of various cell lines

The presence of serum in cell culture raises safety problems for the production of biologicals, thus a new serum-free medium (MDSS2) was developed. The evaluation of this medium for the growth of different cell lines (BHK-21 C13, BSR and Vero) has shown that cells grew in this medium similarly to standard serum-containing medium, independently of the culture system used: in static (as monolayer) as well as in agitated systems (in suspension in spinner and perfusion reactors). BHK-21 and BSR cells grew as aggregate cultures and could proliferate in both static and agitated culture systems. Vero cells stayed attached to a substrate and proliferated equally in static and in agitated microcarrier-culture systems. The cell densities obtained with BHK-21 cells depended only on the culture system used. They ranged from 2–3×10⁶ to 6–12×10⁶ cells per ml for static batch and perfusion reactor cultures respectively. The cell concentration was 3 to 6 times higher than in classical cultures performed in serum-containing medium. The cell densities obtained with Vero cells were indistinguishable from those obtained in serum-containing medium, whatever the cell culture system used. These cell lines have been used for the production of rabies virus. With respect to BHK-21 and BSR, similar production rates of rabies glycoprotein have been found as in the standard roller bottle process. The production of rabies virus and of viral glycoprotein by Vero cells cultivated in serum-free medium was augmented 1.5-fold and 2.5-fold, respectively, when compared to serum-containing medium.A recombinant BHK-21 cell line, producing human IL-2, can also proliferate in MDSS2, after addition of insulin. The specific IL-2 production rate was augmented 3–4 fold in comparison to serum-containing medium.For the cells tested, the MDSS2 serum-free medium is a good growth and production medium. Its use for cultivating other cell lines and/or for the production of other biologicals is discussed.     

转瓶培养与生物反应器微载体培养乙脑病毒的比较

分别用15L转瓶与15L生物反应器微载体(2.5g/L CytodexⅢ)系统培养Vero细胞并接种乙型脑炎病毒(简称乙脑病毒)。转瓶培养Vero细胞7~8d,细胞数最高能达到8×108;当单层细胞长至3.0~4.5×108时接种乙脑病毒,病毒滴度能达到6.5~6.98 lg PFU/ml,并能够连续收获4~5次;采用微载体系统培养Vero细胞,细胞密度最高能达到170×108;当单层细胞长至60~70×108时接种乙脑病毒,病毒滴度能达到7~7.5 lg PFU/ml,并能够连续收获13~15次。两种方式培养的乙脑病毒收获液分别经灭活、浓缩、柱层析纯化后制备Vero细胞乙脑纯化疫苗,各项检定指标均符合《中国药典》的相关要求。