Hela cell contamination? - (Nov/21/2007 )

Hey,
I've been culturing Hela cells for a while. Over the last week, it seems that my cells have become contaminated. The cells grew fine then over two days the culture was covered with tiny objects just floating around. I tried washing the culture out but the contamination seems to keep growing. I've attached a picture. Does anyone know what is causing the contamination?

THanks,
joe

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It doesn't look like bacteria contamination. To it looks like sediments from your medium. Are you using the last bit of your medium? Fungus is another possibility.

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Dear veryslowjoe,

It looks to me like a yeast infection, however to be sure, do you have an image of greater magnification. Washing of the culture in general will not get rid of the contamination. Go back to the "master bank" and start again. It is very unwise to treat the cells with a concentrated antibiotic/antimycotic dose as the cells will ahve already expressed genes/proteins in response to the yeast presence.

Kindest regards

Rhombus

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It does have some yeast-like qualities.
Is your medium turning yellow?

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why am i constantly agreeing with rhombus
(one day we WILL have an argument)

contamination is contamination - who cares what its called. dump your cells and start again (you'll just drive yourself nuts if you dont)

i've gotten to the stage that if my cells look at me funny i dump them

(i had rho zero's that turned out not to be, the replacements were bacterially infected and mycoplasma positive - if i'd tried treating or fixing i'd still be at it now - and a lot less calm)

better luck next time

dom

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Dear "Dominic",

Thank you for agreeing with me again....you know it makes sense !!!!!!

I just try to pass on my many years of experience onto unsuspecting victims.... today for example in my Institute a new group leader and his new technician. Between them many years of TC experience.... my first question is always......FYRITE.
Again they both looked at me blankly..... both had no idea what I was talking about.

If you do not fyrite your CO2 Incubator regularly, you will be introducing massive errors into your experimental results.
I assume everyone on this forum REGULARLY gets their Gilsons/Brandt/Eppendorf pipettes tested for accuracy and precision.

WHY WHY WHY do scientist's not check their CO2 Incubators for precise and accurate CO2 levels.

IN ALL CELL PAPERS... materials and methods.... the cells were grown in a humidified CO2 incubator at a CO2 concentration of 5%.


Dear Dominic, in all things TC, Rhombus is a self proclaimed expert....please goggle Professor Salvador Moncada....he has trusted me over the past 23 years.

Kindest reagards

Rhombus

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talking about yourself in the third person - never a good sign

(actually i do owe you - you saved me a lot of hassle and heartache when everything went pear shaped so thanks for that)

although your constant listing of acheivments still makes me giggle

dom

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Probably dumb question but what the f** is Fyrite??
And do not assume anything Rhombus. I always thought of myself as a person/scientist who knows how to do things well and won't do it otherwise. But since now I have a boss that just gave up on testing for Mycoplasma because all our cell lines were positive.. And I don't want to get fired...

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this is a fyrite tester. you can tell I'm old-school, because I have one of these and not the digital version - anyways, they test CO2 levels.

I agree that CO2 regulation is a common problem. when my cells seem a little funny, the first thing I check is the water pan....the second is the CO2 level.

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Not the most accurate way, but you can tell by the color of the medium. It turns yellow (without cells) when CO2 is too high, pink when the opposite.

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