Contamination in primary cell culture
Posted 16 November 2004 - 06:13 PM
I really do not know if this is the right forum to ask this question. Our lab does a lot of primary cell culture work like T cells and DC. The last week there has been a problem of contamination.
There are wriggly structures, highly motile, no visible flagella, like tiny specks. It was first thought to be cell debris, but they are motile and seem to have penetrated some of the cells or look like swarming inside the cells. Cells look healthy and no pH change in media or obvious turbidity. I have been reading about mycoplasma contamination, however most references state that mycoplasma contamination is usually invisible and detected by PCR kits.
How slowly does yeast grow on primary cell cultures, as some of the cultures were seven day old and it did not look like the organism had taken over even after 24 hours.
could you please help.
Posted 17 November 2004 - 02:28 PM
They could possibly be confused for debris, but are actually a
strange strain of bacteria as evideniced by the propigation of the speckles?
It has been my experience that this is not a form of myoplasm, but exhibit
characteristics similar to this. We have found that this form of contamination
comes from a water bath and grows in serum. BAsically, someone contaminated
their serum with water bath water.
If you have these in your cells, you may try to get rid of them by culturing in high doses of antibiotics.
However, we have found that once these little guys are in a group of cells, well basically, resitance is futile. The cells should be trashed. If even a few of these cells are added to a new flask, the bacterium will be carried over on the cell wall (??).
Posted 18 November 2004 - 12:46 PM
What I suggest is to throw the cells away, usually the whole batch because they come from the isolation process. But, if you really want to try to save the cells, try the followings. First, wash cells with PBS extensively. Then trypsinize the cells and centrifuge. Use lowest speed (50g, 2 min) to make sure only the cells were spinned down. Pass the cells in to clean dishes using medium containing P/S, gentamycin, and tetracycline. Fungazon is another choice. Repeat one day after if necessary. After two or three passages, cells will look better, then go back to normal culture. This is under the assumption that your primary cells can tolerate such procedures.
Posted 26 January 2005 - 09:12 AM
I was just checking (almost all the net!!) about different existing cell culture contaminants.
Because I observe the same kind of problems in my cell cultures, little spots in the supernatant, where i first thougt about debries and now in the cytoplasma where they seem to multiply... really strange : no pH variation, and really slow growing rateof this spots, so the high doubling rate cells are ok , whereas others slow growing cells are more affected. Mycoplasma test is negativ. And i was looking on my flask during 10 minutes: are they moving or is it just brownian movement...?!!!
I need some help
Posted 27 January 2005 - 09:51 AM
so, keep the cell will definitely waste ur time,ur money as well. i suggest put them all in trash, start the new one. or further ur project on the bacteria as extra parameter!