What is conditioned media???

Conditioned media is media that cells that cells have been cultured in for a period of time as opposed to media fresh out of the bottle.  Cells "condition" the media by releasing/secreting proteins, cytokines, chemicals, etc. into it - which they do normally.  You can take the conditioned media and identify any cytokines that have been secreted by the cells and measure their concentrations.  You could treat the cultures with various drugs or chemicals and examine if the cytokine profile changes, or you could compare the cytokine profles of various cell types, etc.