Invitogen cell countess - (Nov/25/2009 )

We just got the new cell countess from invitrogen and was wondering if any one else is using this equipment for cells

I don't because of the need to buy their cuvettes for this instrument, they are quite expensive and not really reusable much.

Yes we use the countess for counting cells for cell culture. We find it works really well and gives a very accurate viablity reading.

I do not have adherent cells and was wondering what type of cells do use for the counter. There seems to be a variability every time that i do the counting ( i think the reason is how i focus the cells )

I count adherent and suspension cells. I think you can count any cell type that isn't a red blood cell. We have found the cell counts to be very tight each time we count. It is true that you have to focus the cells each time but this mainly affects the viability reading and not the live cell count.

I use Countess to count hybridomas in cell cloning. It's a good and an objective method to count this kind of cells. Cell concentration values are similar to obtained after cell count on hemacytometer (neubauer chamber).

For cell fusions we do not use cell countess because splenocytes, that are smaller than myeloma cells and hybridomas, give some errors on cell concentration values measured by cell countess, probably, because these cells are not too refringents, and/or they can't be focused very well on equipment, and cell count results are not similar to Neubauer chamber as other counts that we do with other cell types.