I was hoping someone could help me. I’ve been culturing lymphoblasts derived from another center to harvest and make chromosome preps. Initially the culture was going fine. We seeded it to keep a back-up and tried harvesting what we had with no success at all. All our cells lysed (we’ve had trouble with this line before, so we want to modify our techinique and start again). The problem is the seed culture isn’t growing well enough for us to try a second harvest. Its a suspension in RPMI. It’s been over a month now and the media has not turned yellow once. Also under the mike, the cells are growing and multiplying (can see clearly numbers going up) but they are not clumping nor is the media changing color. Can anyone tell me whats going on please?