Expi293F™ GnTI- Cells - FAQs

查看更多产品信息 Expi293F™ GnTI- Cells - FAQs (A39240)

8 个常见问题解答

我能让Expi293F培养细胞表达蛋白长达7天以上吗?

Expi293F细胞的生长和表达属性决定了在转染7天之后,培养基将临近耗竭,并应该已经达到最高蛋白表达量。继续孵育将导致培养细胞活力的显著下降。

若使我的Expi293F细胞生长至比推荐指标更高的细胞密度,它们还能用吗?

尽管Expi293培养基能够支持更高的细胞密度,但我们并不推荐以超出5–6 x 10e6个细胞/毫升的密度来培养Expi293细胞,因为这会降低后续的转染和蛋白表达效率。在更高的细胞密度时,遇到培养活力降低临界点的可能性也会增加。如果您培养的细胞超出5–6 x 10e6个细胞/毫升,请按照手册中的描述传代一至两次,监控它们的活力和生长速率。使用蛋白表达对照IgG或得率已知的表达载体来测试转染效果,从而确定细胞表达性能是否受到影响。

Can I leave my Expi293F culture expressing for more than 7 days?

The growth and expression characteristics of Expi293F cells are such that, by 7 days post-transfection, the culture medium should be close to being spent and maximal protein expression should have already been achieved. Continued incubation will result in a large decrease in cell culture viability.

Find additional tips, troubleshooting help, and resources within our Protein Expression Support Center.

If I let my Expi293F cells grow to a higher density than recommended, will they be okay?

While the Expi293 Expression Medium can support much higher cell densities, we do not recommend growing your Expi293F cultures beyond 5-6 x 10e6 cells/mL, as subsequent transfection and protein expression efficiencies may be reduced. At higher densities, there is also the increased possibility of reaching the point of reduced culture viability. If your seed culture does exceed 5-6 x 10e6 cells/mL, passage them once or twice as detailed in the manual, monitoring them for viability and growth rate. Perform a test transfection using the Protein Expression Control IgG or an expression construct of known yield to determine if cell expression performance has been impacted.

Find additional tips, troubleshooting help, and resources within our Protein Expression Support Center.

What method do you recommend for quantifying rabbit IgG expression from pRABBIT IgG IRES-EmGFP Positive Control Vector, Cat. No. A39243?

The formation of intact IgG molecules may be quantified using a sandwich ELISA designed to capture and detect rabbit IgG. Besides the rabbit IgG positive control vector, reagents, and consumables that are included in the kit, you will also need purified rabbit IgG to be used as a standard, F(ab')2-Goat anti-Rabbit IgG (H+L) Cross-Adsorbed Secondary Antibody, HRP (Cat. No. A10547), Protein A Coated Plates, Clear, 96-Well (Cat. No. 15130), TMB Substrate Kit (Cat. No. 34021), SuperBlock (TBS) Blocking Buffer (Cat. No. 37535), and PBS or TBS buffer for washes. There is an example procedure in our Protein A Coated Plates manual (https://tools.thermofisher.com/content/sfs/manuals/MAN0011310_Thermo Scientific_ProteinA_G_AG_Coat_96Well_UG.pdf). Please note that our R&D scientists determine titer values from crude cell culture supernatants using a Pall Life Sciences FortéBio Octet instrument equipped with a Protein A biosensor.

Find additional tips, troubleshooting help, and resources within our Protein Expression Support Center.

Do you offer a GFP-expressing mammalian expression vector that I can use as a control to monitor my transfection and expression with the Expi systems?

We offer pRABBIT IgG IRES-EmGFP Positive Control Vector, Cat. No. A39243, which you can use to monitor your transfection and expression.

Find additional tips, troubleshooting help, and resources within our Protein Expression Support Center.

How do I culture Expi293F GnTI-, Expi293F Inducible, or Expi293F Inducible GnTI- cells?

Expi293F GnTI-, Expi293F Inducible, and Expi293F Inducible GnTI- cell lines were derived from the parental Expi293F Cells (Cat. No. A14527) and therefore, share similar morphology and growth characteristics. They are cultured in Expi293 Expression Medium and transfected using ExpiFectamine 293 Transfection Kit following our standard Expi293 protocol.

Find additional tips, troubleshooting help, and resources within our Protein Expression Support Center.

How soon after thawing can I use my Expi293F cells and for how long are they good to use?

Expi293F cells must be recovered from freezing and passaged at least 3 times using the procedure outlined in the manual to ensure optimal performance. Cells should maintain performance for at least 30 passages if maintained in accordance with the protocol in the manual.