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nih3t3 - is this contamination? - (Feb/01/2008 )

Hi - this is an image of NIH3T3 cells - http://www.comfx.com/v.php?d=573418

Do you know what those chunky patches that the cells are aggregating around are? It doesn't look normal. There was this one flask that had huge visible (1cm^2) patches floating around and under microscope it looks like bigger versions of these blobs.

Thanks,
- Eli

-eli2k-

I've seen similar when I let my 3T3 cultures get over confluent like 100%+ and I figured they were lifting off of the bottom. Do you always split these cells before they get 100% confluent?

-unique317-

QUOTE (eli2k @ Feb 2 2008, 12:30 AM)
Hi - this is an image of NIH3T3 cells - http://www.comfx.com/v.php?d=573418

Do you know what those chunky patches that the cells are aggregating around are? It doesn't look normal. There was this one flask that had huge visible (1cm^2) patches floating around and under microscope it looks like bigger versions of these blobs.

Thanks,
- Eli

NO, I don't think that is contamination....the cells are just aggregated. Since your cells aren't quite confluent, I'm guessing that the 'blobs' are masses of cells that packed together during the centrifugation step of passiaging and were not completely dispersed prior to being plated. Just a hunch....

-JAH-

I did experience the same thing with 3t3-l1 cells. These seemed like cell clumps, as sait JAH. So don't worry, your cells aren't contaminated!

-Madrius-

I haven't been passaging them correctly. They seem fine in the morning, and I wait until evening to passage and they are even more full...so I might start with a lower passage vial I froze down before and be more careful with them. Thanks.

-eli2k-

It doesn't look like contamination. I think the colonies are cell aggregates. May be the cells are not in single cell suspension when you passage them.

-Franz K.-

QUOTE (eli2k @ Feb 1 2008, 10:30 PM)
Hi - this is an image of NIH3T3 cells - http://www.comfx.com/v.php?d=573418

Do you know what those chunky patches that the cells are aggregating around are? It doesn't look normal. There was this one flask that had huge visible (1cm^2) patches floating around and under microscope it looks like bigger versions of these blobs.

Thanks,
- Eli


Dear eli2k

They are definetely cell aggregates. When trypsinising the cells, the aim is to get single cell suspensions, so that you get as many cells as possible to grow. If you under trypsinise or triturate to softly, then aggregates will form. The cells on the outer edges of the aggregate will grow, the cells in the middle of the aggregate will die.

Hope this is useful

Rhombus

-Rhombus-

QUOTE (Rhombus @ Feb 5 2008, 09:01 AM)
Dear eli2k

They are definetely cell aggregates. When trypsinising the cells, the aim is to get single cell suspensions, so that you get as many cells as possible to grow. If you under trypsinise or triturate to softly, then aggregates will form. The cells on the outer edges of the aggregate will grow, the cells in the middle of the aggregate will die.

Hope this is useful

Rhombus



Thanks Rhombus and everyone else - my PI thinks it is due to aggregates also. I'll try to titurate more to ensure single cell suspension, hopefully that will fix the problem.

-eli2k-