Repeat bacterial infections - Trying to find the source (Dec/20/2010 )
It started last week when I came in and all of my cells (A549) had a bad bacterial infection that killled them.
Media is DMEM, 10% FBS, 2% strep/pen
I thawed out a new vial, looked fine for 2 days, then they developed a bacterial infection and died.
Thawed out a second vial, looked good for 3 days, then they devloped a bacterial infection over the weekend and died.
I cannot find the source of the repeat infections. I used brand new media, brand new cell flasks, cell flaks from a different manufactor, put the cell flask in a different spot in the incubator, and ramped up the pen/strep to 5%. Yet, still my cells got a bacterial infection and died while all the other cultures in the incubator are doing fine.
What in the world can be causing these infections? I liberally spray all materials and the area in the fume hood that I'll be working in with 75% ethanol as well as leave the UV light on in the hood every time I finish. Help?
In the cell stocks?
Hola In my hands gentamycin is more effective to avoid infections than Pen/Strep. Next time ,if you want, seed the cells in medium with gentamycin. and a little volume without antibiotic in a little plate or in a well of a plate, and if you want other little volume with P/S . if the contamination is in the stocks , resistant to P/S, and sensible to gentamycin you will have yor plates OK and both control contaminated. Buena suerte y Feliz Navidad
Thank you for you responces. I will give the gentamycin a try. What percentage do you recommend?
The thing I find odd, but possibly unrepeated, is I've never had a problem with bacterial infections before. Then 2 weeks ago the cells devloped a bacterial infection and died. Thats when I began to thaw out new vials, and these too developed bacterial infections. Is there possibly a link between the original infection 2 weeks ago and these repeat infections?
When I froze the stock down the cells were healthy and free of any signs of a bacterial infection. Furtheremore, I thawed out 1 vial each time I froze down several vials to check the viability, and had no problems with bacterial infections with these cells in the weeks after thawing.
dw237606 on Tue Dec 21 14:28:35 2010 said:
Thank you for you responces. I will give the gentamycin a try. What percentage do you recommend?
The thing I find odd, but possibly unrepeated, is I've never had a problem with bacterial infections before. Then 2 weeks ago the cells devloped a bacterial infection and died. Thats when I began to thaw out new vials, and these too developed bacterial infections. Is there possibly a link between the original infection 2 weeks ago and these repeat infections?
When I froze the stock down the cells were healthy and free of any signs of a bacterial infection. Furtheremore, I thawed out 1 vial each time I froze down several vials to check the viability, and had no problems with bacterial infections with these cells in the weeks after thawing.
Water bath?
dw237606 on Tue Dec 21 14:28:35 2010 said:
Thank you for you responces. I will give the gentamycin a try. What percentage do you recommend?
Hola the usual concentration of gentamicyn is 50ug/ml. Buena suerte
Hi dw,
possible for you to subculture your bacteria and try to identify it? Is hard to say which antibiotics is good for your case.
I will try to subculture the bacteria, but that will be challening since the school is shutting down for the next week or so. If I'm able to do so, I will report back with the ID asap. Thanks.