Problem with U937 - (May/15/2005 )

I'm culturing U937 using RPMI 1640 with 10%FCS but it doesn't seem to grow. Does anyone have experience with this cell line and might give me some suggestion as to how to go about doing this? I've seen report about adding lipoproteins to enhance growth of U937. Has anyone tried this?

And i've never actually seen this cell line before. Can anyone describe how it looks like, esp the size. My cells look really small even under 200x mag.

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Hi,

I've recently started growing these cells and they grow fine in RPMI 1640 supplemented with 10% FCS with a doubling time of about 24 hr. The cells are small and spherical with a tendency to cluster. I'm not sure of the size.

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Hi all,

i am currently trying to culture the U937 cells which were bought from ATCC.. this is my 2nd purchase.
my first purchased was contaminated during the first thawing. the contaminants or suspect were seen as moving particles which is uninfluenced by external vibrations or etc. therefore i thought that it might be human error and so i did another purchase.
this time after thawing, i saw tht the cells were also contaminated by the same particles. i left it overnight and the next day under a 400X phase contrast microscope, this is what i saw.



this is the second time the moving particles were seen. is this a natural occurence in the U937 culture? or is there something wrong with the original cells from ATCC...
need help badly...
thank you

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It's hard to tell if this is really a contamination. After thawing cells, you always have a lot of debris floating around from dead cells. If I were you, I'd keep them in culture and see if the medium changes and becomes what you'd expect it to become when contaminated. Also: check if the number of particles floating around increases and if your cells behave badly.

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hi geejun2 ! vairus is right you should allow your cells first to come out of the shock, acclamatise and multiply. the cells which you have shown as contaminants look like debris to me. so do not bother about the contiminants first. change the media and see. if it is contamination it will reappear again and if it is debris, it is removed and you should not find any or little of that shown in the picture.
all the best

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it seems that the cells are not behaving normally. got a reply from ATCC and they replied tht there isn't any gurantee of cell sterility outside their labs...



yup
changed the media and it is being cultured. part of the cells are being treated with high dosage of antibiotics and fungizone. anyway, i'll try to get a photo of the cells again next week after i leave it to multiply....
this is already the 2nd time... real bad....



ONE IMPORTANT MATTER HERE>..
the particles can be seen to be vibrating....

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erm.. so how is your cells? are they ok? mine having contamination problems..

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Hi geejun2,

I bought U937 recently and I had the same problem. I have seen the particles "moving" like you describes, but it doesn´t proliferate. I don´t think it is contamination, our assays are runing well.

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Hi, terracotta

U937 needs a high concentration to grow, between 1x10E5 and 1x10E6 cels/ml. A possible reason why your cells doesn´t grow is a lower concentration.

I hope that I help you.

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