CHO-K1 Cells
Basic details about the CHO-K1 cell line
Description | CHO-K1 cells are a subline derived from the CHO cell line, which was originally established in the early 1950s from a Chinese hamster ovary. CHO-K1 cells are widely utilized in the production of therapeutic monoclonal antibodies and other biopharmaceuticals. Their extensive use in biopharmaceutical protein production and vaccines is attributed to their eukaryotic nature, which allows for proper folding, assembly, and post-translational modifications such as glycosylation, which influences the stability, efficacy, and safety of the produced proteins. In the realm of recombinant protein production, the CHO-K1 cell line is used to express a wide array of proteins, including monoclonal antibodies, growth factors, cytokines, and enzymes. These proteins have applications in therapeutic treatments, diagnostic assays, and vaccine formulations. CHO-K1 cells exhibit a robust growth rate and are adaptable to various culture conditions, including suspension and adherent cultures, making them highly valuable for large-scale bioproduction processes. They possess a high level of genetic stability and are used for stable cell line development as they are capable of amplifying and expressing exogenous genes efficiently, which is critical for producing high yields of recombinant proteins. CHO-K1 chinese hamster cells can be easily transfected with a variety of vectors for gene expression, facillitating gene editing or knockdown. This flexibility allows researchers to introduce specific genes, silence genes, or even perform targeted gene editing using technologies like CRISPR-Cas9 in CHO-K1 host cells. In conclusion, the chinese hamster CHO-K1 cells and CHO cells are pivotal in biotechnological research and biopharmaceutical production, offering a versatile platform for the study of gene function and the large-scale production of recombinant proteins. |
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Organism | Hamster |
Tissue | Ovary |
Applications | This cell line is an optimal choice for toxicology, industrial biotechnology and bioproduction. |
Synonyms | CHO K1, CHOK1, CHO cell clone K1, GM15452 |
Properties of CHO-K1 cells
Age | Adult |
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Gender | Female |
Morphology | Epithelial-like |
Growth properties | Monolayer, adherent |
Documenation
Citation | CHO-K1 (Cytion catalog number 603480) |
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Biosafety level | 1 |
Genetic characteristics of the chinese hamster ovary cell line CHO
Virus susceptibility | vesicular stomatitis (Indiana), Getah virus Virus Resist: poliovirus 2, modoc virus, Button Willow virus |
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Reverse transcriptase | negative |
Karyotype | Chromosome Frequency Distribution 50 Cells: 2n = 22. Stemline number is hypodiploid |
Culturing guidelines
Culture Medium | Ham's F12, w: 1.0 mM stable Glutamine, w: 1.0 mM Sodium pyruvate, w: 1.1 g/L NaHCO3 (Cytion article number 820600a) |
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Medium supplements | Supplement the medium with 10% FBS |
Passaging solution | Accutase |
Doubling time | 22 hours |
Subculturing | Remove the old medium from the adherent cells and wash them with PBS that lacks calcium and magnesium. For T25 flasks, use 3-5 ml of PBS, and for T75 flasks, use 5-10 ml. Then, cover the cells completely with Accutase, using 1-2 ml for T25 flasks and 2.5 ml for T75 flasks. Let the cells incubate at room temperature for 8-10 minutes to detach them. After incubation, gently mix the cells with 10 ml of medium to resuspend them, then centrifuge at 300xg for 3 minutes. Discard the supernatant, resuspend the cells in fresh medium, and transfer them into new flasks that already contain fresh medium. |
Split ratio | A ratio of 1:4 to 1:8 is recommended |
Seeding density | 1 x 10^4 cells/cm^2 will yield in a confluent layer in about 6 days |
Fluid renewal | 2 to 3 times per week |
Freezing recovery | After thawing, plate the cells at 5 x 10^4 cells/cm^2 and allow the cells to recover from the freezing process and to adhere for at least 24 hours. |
Freeze medium | CM-1 (Cytion catalog number 800100) |
Handling of cryopreserved cultures |
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Quality control
Sterility | Mycoplasma contamination is excluded using both PCR-based assays and luminescence-based mycoplasma detection methods. To ensure there is no bacterial, fungal, or yeast contamination, cell cultures are subjected to daily visual inspections. |
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Required products
One of its notable advantages is the ability to support cell growth without the need for serum supplementation. This eliminates potential interference caused by serum components, ensuring consistent and reliable experimental results. By providing a serum-free culture environment, Ham's F-12 Medium offers researchers greater control over their investigations.
Another key feature of Ham's F-12 Medium is its suitability for single-cell plating. This makes it an excellent choice for a variety of cell lines, including CHO cells, lung cells, and mouse L cells. The medium's optimized nutrient composition facilitates efficient attachment and growth of individual cells, enabling the establishment of homogeneous cell cultures with improved reproducibility.
Moreover, Ham's F-12 Medium has gained recognition as the preferred medium for the Clonal Toxicity Assay (CTA). This assay plays a critical role in assessing the cytotoxic effects of substances on cells. By utilizing Ham's F-12 Medium in the CTA, researchers can accurately evaluate the impact of various compounds or treatments on individual cells, providing valuable insights into toxicological profiles.
Quality control
pH = 7.2 +/
- 0.02 at 20-25°C.
Each lot has been tested for sterility and absence of mycoplasma and bacteria.
Maintenance
Keep refrigerated at +2°C to +8°C in the dark. Freezing and warming up to +37° C minimize the quality of the product.
Do not heat the medium to more than 37° C or use uncontrollable sources of heat (e.g., microwave appliances).
If only a part of the medium is to be used, remove this amount from the bottle and warm it up at room temperature.
Shelf life for any medium except for the basic medium is 8 weeks from the date of manufacture.
Composition
Components
mg/L
Inorganic Salts
Calcium chloride x 2H2O
44,00
Copper(II) sulfate x 5H2O
0,00
Iron (II) sulfate x 7H2O
0,83
Magnesium chloride x 6H2O
122,00
Potassium chloride
223,65
Sodium chloride
7599,00
di-Sodium hydrogen phosphateanhydrous
142,04
Zinc sulfate x 7H2O
0,86
Other Components
D(+)-Glucose anhydrous
1801,60
Hypoxanthine
4,08
Linoleic acid
0,08
DL-α-Lipoic acid
0,21
Phenol red
1,20
Putrescine x 2HCl
0,16
Sodium pyruvate
110,00
Thymidine
0,73
NaHCO3
1176,00
Amino Acids
L-Alanine
8,91
L-Arginine x HCl
210,70
L-Asparagine x H2O
15,01
L-Aspartic acid
13,31
L-Cysteine x HCl x H2O
35,12
L-Alanyl-L-Glutamine
217,30
L-Glutamic acid
14,71
Glycine
7,51
L-Histidine x HCl x H2O
20,96
L-Isoleucine
3,94
L-Leucine
13,12
L-Lysine x HCl
36,54
L-Methionine
4,48
L-Phenylalanine
4,96
L-Proline
34,53
L-Serine
10,51
L-Threonine
11,91
L-Tryptophan
2,04
L-Tyrosine
5,44
L-Valine
11,71
Vitamins
D(+)-Biotin
0,01
D-Calcium pantothenate
0,24
Choline chloride
13,96
Folic acid
1,32
myo-Inositol
18,02
Nicotinamide
0,04
Pyridoxine x HCl
0,06
Riboflavin
0,04
Thiamine x HCl
0,34
Vitamin B12
1,36
Key features of Freeze Medium CM-1 include:
Broad Compatibility: Effective for a wide range of cell types, including primary cells, stem cells, and established cell lines.
High Viability: Optimized to maximize post-thaw cell recovery and viability, ensuring reliable experimental outcomes.
Ready-to-Use: Conveniently prepared and sterilized for immediate application, reducing preparation time and risk of contamination.
Enhanced Stability: Maintains consistent performance under standard cryopreservation conditions, ensuring reproducible results.
Long Shelf Life: CM-1 is a serum-containing, ready-to-use cryopreservation medium that can be stored in the refrigerator for up to one year.
Using CM-1 for Freezing Cells
To use CM-1 for freezing both adherent and suspension cells, follow these steps:
For adherent cells, wash and dissociate them from the culture substrate. For suspension cells, proceed directly to the next step.
Count the cells to ensure they are at the proper concentration.
Centrifuge the cells to pellet them, then resuspend in CM-1 freeze medium.
Transfer the resuspended cells into cryovials.
Use a slow-freezing method before transferring the cells to long-term storage.
🥶 Method
🔍 Description
💡 Steps
❄️
Manual Freezing
A step-by-step method involving gradual temperature reduction to ensure cell viability.
1️⃣ Place cells in freeze medium in a 4°C freezer for 40 minutes.
2️⃣ Transfer to a -80°C freezer for 24 hours.
3️⃣ Store cells in liquid nitrogen for long-term preservation.
🧊
Using Mr. Frosty
A convenient device that allows for controlled freezing rates without electrical power.
1️⃣ Prepare cells in cryovials with freeze medium.
2️⃣ Place cryovials in Mr. Frosty container.
3️⃣ Store at -80°C for 24 hours before transferring to liquid nitrogen.
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Controlled-Rate Freezer
A high-precision freezer by Thermo Fisher or other manufacturers designed for controlled temperature reduction.
1️⃣ Program the device to gradually decrease the temperature.
2️⃣ Place prepared cells in the freezer.
3️⃣ After the freezing cycle, transfer cells to liquid nitrogen.
Store the cryovials at temperatures below -130°C or in liquid nitrogen for long-term preservation.
Ingredients
Contains FBS, DMSO, Glucose, Salts
Buffering capacity: pH = 7.2 to 7.6
Cytion’s Freeze Medium CM-1 offers a reliable solution for cryopreservation, ensuring high cell viability and functionality post-thaw for a wide range of research applications.
- A Gentle Alternative to Trypsin
Accutase is a cell detachment solution that is revolutionizing the cell culture industry. It is a mix of proteolytic and collagenolytic enzymes that mimics the action of trypsin and collagenase. Unlike trypsin, Accutase does not contain any mammalian or bacterial components and is much gentler on cells, making it an ideal solution for the routine detachment of cells from standard tissue culture plasticware and adhesion coated plasticware. In this blog post, we will explore the benefits and uses of Accutase and how it is changing the game in cell culture.
Advantages of Accutase
Accutase has several advantages over traditional trypsin solutions. Firstly, it can be used whenever gentle and efficient detachment of any adherent cell line is needed, making it a direct replacement for trypsin. Secondly, Accutase works extremely well on embryonic and neuronal stem cells, and it has been shown to maintain the viability of these cells after passaging. Thirdly, Accutase preserves most epitopes for subsequent flow cytometry analysis, making it ideal for cell surface marker analysis.
Additionally, Accutase does not need to be neutralized when passaging adherent cells. The addition of more media after the cells are split dilutes Accutase so it is no longer able to detach cells. This eliminates the need for an inactivation step and saves time for cell culture technicians. Finally, Accutase does not need to be aliquoted, and a bottle is stable in the refrigerator for 2 months.
Applications of Accutase
Accutase is a direct replacement for trypsin solution and can be used for the passaging of cell lines. Additionally, Accutase performs well when detaching cells for the analysis of many cell surface markers using flow cytometry and for cell sorting. Other downstream applications of Accutase treatment include analysis of cell surface markers, virus growth assay, cell proliferation, tumor cell migration assays, routine cell passage, production scale-up (bioreactor), and flow cytometry.
Composition of Accutase
Accutase contains no mammalian or bacterial components and is a natural enzyme mixture with proteolytic and collagenolytic enzyme activity. It is formulated at a much lower concentration than trypsin and collagenase, making it less toxic and gentler, but just as effective.
Efficiency of Accutase
Accutase has been shown to be efficient in detaching primary and stem cells and maintaining high cell viability compared to animal origin enzymes such as trypsin. 100% of cells are recovered after 10 minutes, and there is no harm in leaving cells in Accutase for up to 45 minutes, thanks to autodigestion of Accutase.
In summary
In conclusion, Accutase is a powerful solution that is changing the game in cell culture. With its gentle nature, efficiency, and versatility, Accutase is the ideal alternative to trypsin. If you are looking for a reliable and efficient solution for cell detachment, Accutase is the solution for you.
Phosphate-buffered saline (PBS) is a versatile buffer solution used in many biological and chemical applications, as well as tissue processing. Our PBS solution is formulated with high-quality ingredients to ensure a constant pH during experiments. The osmolarity and ion concentrations of our PBS solution are matched to those of the human body, making it isotonic and non-toxic to most cells.
Composition of our PBS Solution
Our PBS solution is a pH-adjusted blend of ultrapure-grade phosphate buffers and saline solutions. At a 1X working concentration, it contains 137 mM NaCl, 2.7 mM KCl, 8 mM Na2HPO4, and 2 mM KH2PO4. We have chosen this composition based on CSHL protocols and Molecular cloning by Sambrook, which are well-established standards in the research community.
Applications of our PBS Solution
Our PBS solution is ideal for a wide range of applications in biological research. Its isotonic and non-toxic properties make it perfect for substance dilution and cell container rinsing. Our PBS solution with EDTA can also be used to disengage attached and clumped cells. However, it is important to note that divalent metals such as zinc cannot be added to PBS as this may result in precipitation. In such cases, Good's buffers are recommended. Moreover, our PBS solution has been shown to be an acceptable alternative to viral transport medium for the transport and storage of RNA viruses, such as SARS-CoV-2.
Storage of our PBS Solution
Our PBS solution can be stored at room temperature, making it easy to use and access.
To sum up
In summary, our PBS solution is an essential component in many biological and chemical experiments. Its isotonic and non-toxic properties make it suitable for numerous applications, from cell culture to viral transport medium. By choosing our high-quality PBS solution, researchers can optimize their experiments and ensure accurate and reliable results.
Composition
Components
mg/L
Inorganic Salts
Potassium chloride
200,00
Potassium dihydrogen phosphate
200,00
Sodium chloride
8,000.00
di-Sodium hydrogen phosphate anhydrous
1,150.00