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Debris or particles in medium - A549 cells and weird particles (Sep/01/2006 )

Hey,

I've recently started working with A549 cells and passaged them for about 3-4 times. I've noticed some particles or debris in the culture medium. It doesn't look harmful though. The color of the medium hasn't changed, the cells look healthy. No Mycoplasma contamination.
Well, the argument now is that colleagues say I should discard them but I still think there's nothing wrong with my cultures.
So does anyone know if these particles are normal for this cell line??? Since they are lung epithelial cells they should be able to secrete surfactant-could this be the explanation for what I see???

-britzelbeere-

I know in many cell lines you will find some debris in the medium. This is not always bacteria but it can be simply dead cells that have been shed into the culture medium. If you are using antibiotics in the medium it may be harder to tell if the debris is just bacteria that are being somewhat supressed by the antibiotics or if it is just debris. If the cells look healthy and are behaving normally I would say passage them a few more times to see if it keeps up or if it gets worse. I would recommend passaging it in antibiotic free media to see if it gets worse or doesn't change. If your cells are still appear viable than I wouldn't throw them out just yet.

-jamie419-

QUOTE (britzelbeere @ Sep 1 2006, 01:38 PM)
Hey,

I've recently started working with A549 cells and passaged them for about 3-4 times. I've noticed some particles or debris in the culture medium. It doesn't look harmful though. The color of the medium hasn't changed, the cells look healthy. No Mycoplasma contamination.
Well, the argument now is that colleagues say I should discard them but I still think there's nothing wrong with my cultures.
So does anyone know if these particles are normal for this cell line??? Since they are lung epithelial cells they should be able to secrete surfactant-could this be the explanation for what I see???



I grow A549 cells, WI 38 cells and a number of other cell lines. I usually don't find any debris in A549 cultures but do find lot of debris in WI 38 cells. This debris is clearly a bi product from the cells because, part od it is still attached to the cell border and part of floats for some time and if the flask is left undisturbed for longer time, the debris gets detached completely and floats freely in the medium. This shows it is either dead cell / cell cluster or some other product in the conditioned medium.
Keep observing your cultures. if you observe any changes, you can easily understand what it is.

--

-scifi-

Hi,

A549 cells produce keratin and don't look very clear in appearance. But if you see debris you might want to consider following points. Debris could be bcoz of serum quality, try using serum from other batch or other company. If you are using too high centrifugation speed, reduce it to 1000 to 1500 rpm. Change the culture medium more frequently and see if the debris disappear. While changing medium wash your cell monolayer with PBS or culture medium. Try to not overgrow the cells.

Hope it helps.

-exploresci-

Excellent advice from exploresci, that should cover all bases.

-Rhombus-