What is the percentage of positive cells from a stable CHO pool after months of selection?

11 August 2024 1 6K Report

I have been generating stable cell clones (antibody production) using the ExpiCHO system + antibiotics selection. Although I have been able to select a few producing clones after months of culturing the stable pool, I find it interesting that only

Subham Basak

Hi Marcus Bezerra

I think the percentage is low in this case.

1. You can try to ascertain transfection efficiency by transfecting GFP as control.

2. you can start with a lower concentration of antibiotic and follow the two-phase selection strategy they recommend, to increase chances of selecting even the low copy number clones.

Subham.

Badges
Science topic

More Marcus Bezerra's questions See All

Can holes for pressure probes in journal bearings modify the original pressure distribution?

It is very common to measure the pressure distribution inside the bearings with pressure probes connected to the oil film through holes in the bush. Once filled and pressurized, the probe lines...

12 June 2024 1,936 0 View

Why does the Barricor mechanical separator heparinized plasma tube showed a positive bias for LDH?

The subject of the study centers on the switch from gel separatory tubes to lithium heparin gel tubes in the clinical laboratory but the study additionally addressed the use of the Barricor...

05 February 2024 5,445 1 View

Is it possible to use the parameters of N719 Dye (such as CB and VB electron density) for my natural dye in SCAPS 1D even though I have different dye?

I am using a natural dye (strawberry, carrots, blueberry, turmeri, spinach , arabica robusca). I have the UV-VIs spectra of each. I can calculate the bandgap energy and HOMO and LUMO levels but I...

08 January 2024 3,965 0 View

I would like to konw if there is a alternative to DJI Terra to pre-process LiDAR data from the Zenmuse L1?

LiDAR data collection and processing

07 December 2023 3,745 0 View

After macerating a plant, how do I concentrate the extracts that the yield would be in solid form, it is neither sticky nor liquid?

Kept seeing studies but the results of their extraction is sticky substances. I do stumble upon studies with vacuuming or water bathing the extracts to dryness, but I am skeptical whether the...

11 November 2023 202 0 View

Does anyone know of a psychometric scale concerning perception of HIV Pre-exposure prophylaxis (PrEP) and evaluation of risky sexual behaviour (RSB)?

I'm looking for a psychometric regarding perception of PrEP and sexual expectancies that have items that also include attitudes/perception of risky sexual behaviour (RSB), i.e., condoles sex,...

24 August 2023 4,028 0 View

Does anyone please know of any measures for perception/attitude to risky sexual behaviour (RSB) that would be appropriate for a diverse demographic?

I need a measure for RSB that I can use for a survey that would encompass a wide and diverse population demographic without restrictions to age, gender, race, sexuality, religion, and lifestyles....

24 August 2023 8,098 2 View

How can I compare different Likert scales of the same population over time?

Dear community, we work on a employee satisfaction (done via questionnaire) project in an organisational setting. For the previous years, the questionnaire hat a 5 point Likert scale for all...

31 March 2023 3,525 5 View

Am interested in High Definition Mapping for driverless cars please advise on available material?

HD Mapping of Driverless Cars

06 March 2023 8,840 2 View

What is the optimal Celsius, Millitorr, and Time to Freeze dry a frozen a aqueous plant extract?

I want to froze an aqueous plant extract at -20 °C for 24 hours, then freeze dry it. I want to know if it's okay to freeze an aqueous extract to -20 °C for 24 hours then freeze dry it when I want...

25 February 2023 8,416 2 View

Why Do TDS and EC Increase with Larger Wastewater Volumes, While BOD and COD Decrease?

I have carried out MFC experiments on three different volumes, 50, 500 and 1000 mL of wastewater. Results after MFC treatment shows that TDS and EC are more in larger volumes of water i.e. TDS and...

09 August 2024 9,621 0 View

Could it be a cell culture contamination?

Hello everyone! I observed in my culture (htert-RPE1 cells) an orange- red particle at the bottom of the dish. It is visible to the naked eye as a very very small red dot. Could it be a...

09 August 2024 2,824 3 View

Mouse CD3 antibody sequence?

Can anyone share any reference that gives mouse specific CD3 antibody sequence. I have been searching for this since few days and no luck. Thank you very much

08 August 2024 9,157 4 View

How to confirm the site-directed mutagenesis result without performing NGS?

I'm cloning a fragment of 3200 nts into plasmid. The cloning was successful, however, 02 amino acids were mutated. Now I want to fix these 02 aa by site-directed mutagenesis technique using...

08 August 2024 4,645 2 View

Is there any way to quantify bacterial and fungal cells in their mixed culture?

I am working in fungal fermentation of soybean meal and there is bacterial growth in them at times. I am trying to quantify fungal cell counts and bacterial cells; but I haven't been able to do at...

07 August 2024 7,535 4 View

Can I use a HisTRAP column for affinity chromatography?

I'm working on selecting antibodies against a recombinant protein that has a His-tag. My idea is to first bind the recombinant protein to a HisTRAP column and then use this column for an affinity...

07 August 2024 505 3 View

Do I need specific antibodies to stain for a fusion protein?

I am staining some brain sections stored in cryoprotectant that express a Histone H2B- GFP fusion protein that were generated ~10 years ago. I know I need to enhance signal with an anti-GFP...

07 August 2024 5,338 2 View

How to normalize and take the significance of the MTT OD values with 3 replicates for the same cell-line?

Hi, I have a question about normalizing the MTT OD values for doing the statistical analysis. So, if we have 3 different plates and we call them 3 different replicates, so, first we would...

07 August 2024 8,106 4 View

Why activated CAR-Jurkat cell could not kill targets?

Previously when I co-coluture anti-CD19(FMC63) CAR-Jurkat with Raji with E:T=5:1, Jurkat can eliminate Raji in 24h. However, when I test another CAR construct, although I can dectect totally CD69...

06 August 2024 641 2 View

How to determine positive-stained cells in FACS? Use isotype or unstained control?

To compare positive and negative cell populations in flow cytometry, should I compare unstained cells with antibody stained cells? Or with the isotype control? Most papers show comparison with...

06 August 2024 6,728 6 View