THP1 monocytes cultured forms "vacuols-like" compartments - (Mar/02/2012 )

Hi !

I rencenty started to use THP1 human monocyte for some projetcts. Defrosting THP1 cryo (conserved -80 Freezer), i notice (optic microscopy) sometime that my cells forms some dense "vacuols-like" structures in cytoplasmic areas!
My interest is created by these structures because they are not present in all my defrosted cells ! I've heard that these structures are "current" for THP1 users... But i would be really pleased if i could have any (part of) explanation concerning the causes of these structures !

I use current protocols to defrost cells ( 3x10e6 cells in 3/4 mL of RMPI + 10%FCS + Additives), and when these structures are forming it is before i started my tests.

Thanks, and have a nice day !

Ex'

Probably either related to senescence or apoptosis.