Cells hyper-sensitive to treatment after 48 hour culture

Debate and discussion of any biological questions not pertaining to a particular topic.

Moderators: honeev, Leonid, amiradm, BioTeam

Post Reply
Posts: 1
Joined: Thu Sep 20, 2012 2:09 pm

Cells hyper-sensitive to treatment after 48 hour culture

Post by danint » Thu Sep 20, 2012 2:20 pm

Hi all,

I've frequented this forum for a while but this will be my first post, hopefully someone will have some insight into my problem!

I'm carrying out protoporphyrin IX based photodynamic treatment of A431 cells and I've recently been having some odd issues with the cells becoming hyper-sensitive to the treatment. To make things more peculiar, they only become sensitive if they're cultured in the treatment flasks for 48+ hours, whereas those cultured for 24 hours produce results consistent with those I have obtained in the past. I must add that all of these experiments are carried out whilst the cells were at the same level of confluence (70-80%).

In the past, culturing my cells for 2-4 days was sometimes necessary to obtain the desired confluence and this didn't negatively effect my experiments in any way. This problem arose some time in July, however I've only just managed to pin down exactly what has been happening.

I've thawed out cells (P11) frozen before these issues arose and yet these suffer in the same manner. Control untreated cells show no signs of dying (annexin V + propidium iodide staining) and are morphologically healthy. I've bought and made up new batches of media, ensured my supplements were the same lot number. I've also checked for mycoplasma infection and that has come up negative and still I'm having these problems.

Can anyone here shed some light on this issue? I know it's a very specific problem, but perhaps someone has had a similar experience with other experiments!

Many thanks :)

Post Reply

Who is online

Users browsing this forum: Google [Bot] and 18 guests