I just recently started cell culture and got my first cells in and already something seems fishy.
I have 2 celllines, MRC-5 and BHK-21. I grow both of them in the same medium (DMEM high glucose +10% FBS).
They both grow, but in the BHK-21 flasks I see a lot of cells detaching and swimming in the medium. And after some time these things here show up:



So far I took some of the supernatant and put it on TSA and SAB agar plates and incubated them at 37°. After 5 days in the incubator there is nothing growing on them yet. Can anyone of you more experienced culture users tell me what I am dealing with here?
Thank you very much in advance.