Black dots contaminant phenonmenon: helpful paper - (May/26/2011 )

Dear all,

It seems like many researcher faced with this bizarre black dancing dots in cell culture, and me too!
So I've search about this issue and found one paper that published in Biologicals 2010.

Gray JS, Birmingham JM, Fenton JI.Got black swimming dots in your cell culture? Identification of Achromobacter as a novel cell culture contaminant Biologicals. 2010 Mar;38(2):273-7. Epub 2009 Nov 18.

This one light up my life (I just order antibiotics that they mention today and hope it works. I hope this paper can help you (and me) to deal with this UFO contaminant.

Cheers!

Mypowerberry

Thanks for sharing this paper. Wow the paper cited a topic in BioForum:

Indeed, mysterious black dots contamination is not uncommon. I am not sure whether all are caused by Achromobacter.

There are several other topics in this forum discussing the black dot phenomenon.
http://www.protocol-online.org/forums/topic/19403-black-dots-in-cell-culture/
http://www.protocol-online.org/forums/topic/12942-black-dots-in-cell-culture
http://www.protocol-online.org/forums/topic/8829-is-this-contamination-or-otherwise
http://www.protocol-online.org/forums/topic/19925-contamination-in-cell-line
http://www.protocol-online.org/biology-forums/posts/33354.html
http://www.protocol-online.org/biology-forums/posts/4305.html
http://www.protocol-online.org/biology-forums/posts/34135.html

and more...

This is an intersting paper !

I find these foolish dots very irritating. Hope it will work.
Thanks for sharing

Mypowerberry on Thu May 26 19:47:53 2011 said:

Hi, Did the antibiotics work ? If so what did you use ? I am having an issue with a transfected cell line and don't want to loose them.

Thanks!

Hi,
Yeah, it works! I use 10 ug/mL both ciprofloxacin and piperacillin. You need to thoroughly wash cells with PBS before add media-contained drug for effective results.

But for the severe contamination, this formula may not enough. One day my friend who culture pancreatic cancer cell line that got harsh level of this black dots asked for help(it covered all the cell surface and even in the bottom of flask +very sticky and cannot wash out with PBS). So I decided to bounce the drugs into the flask (cannot remember the exactly Conc., maybe 100ug/mL each but you may need to guess about the tolerance of your cells). Finally, I can eradicated it and cells can spread healthily after that.
ps. I can show you a before and after pic but I can't find an attach button in this website.

Mypowerberry,

When you say wash the cells with PBS, do you mean washing adherent cells? Why is this needed? What happens if you don't wash them in PBS? Thanks!

Hi Jonahsacha,

Yes, I mean adherent cells and I suggest to wash cells (in flask) with PBS because I need to eliminate the Black dots as much as I can before add the drug. So after wash cells, we can see only a few of contaminant that can be killed effectively by drugs (with low concentration that not affect our cells). For me, I wash cells at least 3 times and change media every 3 days for 20 days.

But sometimes it come back again, it may come from environment, air ventilation, water bath, lab coat or our skin or whatever, so we need to check and reduce risk factor. For me, after I avoid water bath to warm up my media and buffer, I think this help and never get infected again.

ps. Be careful, the drug can contaminate by other bacteria or other organism as well