If fibroblast cells had been washed and flushed the floating cells out before dissociation and staining process, should only viable cells or total cells be counted for PDT calculation ?
Normally, a culture of healthy normal fibroblasts (and other attached cell types) contains mostly cells that are firmly attached and a fraction of cells that are floating (mitotic cells). When cells are seeded at low density (~20-25%) in the presence of optimum growth factors, cells double asynchronously in the culture. Therefore, both attached and floating mitotic cells need to be included in counting when calculating PDT.