Trypsin the cell killer - How much death does trypsin actually cause (Oct/14/2009 )

I know trypsin isn't good for cells but how bad is "not good"
We had a presentation once on it where they said it can cause up to 80% of cells to undergo apoptosis. This seems very high.

Im sure it all depends on cell type etc but does anybody perhaps have an answer to this? If anybody could paste links to references that mention anything about apoptosis due to trypsin I would greatly appreciate it!

Stephan on Oct 14 2009, 09:40 AM said:

Hello!

Although I cannot provide direct literature links, I can tell from personal experience that there is a concentration range of trypsin media with e.g. 0.05% to 0.25% trypsin. The last time I counted primary cells after trypsinisation with the trypan blue test, I got 1-2% dead cells (or less). There is no other way than empirical testing how long the cells require trypsinisation (a range between 1 and 10 minutes).

Good luck!

Stephan on Oct 14 2009, 09:40 AM said:

Dear Stephan,

Trypsin is used to remove cells from the TC plastic. Traditionally the cells are washed first with PBS (w/o Calcium and Magnesium Ions) and in the presence of EDTA, a CHELATOR of Divalent cations. Trypsin is inhibited by divalent cations. The concentration of trypsin depends upon the cell type you use. The length of time the trypsin is in contact with the cells is also very important. Trypsin can be PINOCYTOSED into the cell and cause intracellular damage...that may result in Apoptosis.
Trypan Blue is not a marker for apoptosis..but is a marker for cell viabilty/death. If a trypan counts gives you a 98% viability count... there will be a % of cells that are in different stages of Apoptosis.
More sensitive testing like Caspase activation/Annexin V assays, will give information about cellular apoptosis.

Hope this is useful.

Kindest regards.

Rhombus