I transduced the SVF preadipocytes with lentivirus and about a month after transduction and selection, now the survived cells are like this. For one like this I observed small lipid droplets at the side, but some are just like this one, big with no characteristics of preadipocyte (should be fibroblast-like). Has anyone met such situation before? Is this still preadipocytes? Why the morphology changed like this?