Effect of human chorionic gonadotrophin on the detachment of human granulosa cells from extracellular matrix layered onto glass or plastic

We have previously shown that human granulosa cells cultured on a thin layer of extracellular matrix (ECM) are lost from culture in the absence of gonadotrophin. We now examine the effect of plating ECM onto glass or plastic. Such a comparison revealed that loss of cells from control cultures was more rapid when ECM was on glass, whereas cultures maintained with human chorionic gonadotrophin (HCG) showed greater stability when ECM was on plastic. The dose range of HCG required for the effect on cell retention was similar to that required for stimulation of progesterone production. Electron microscopy of cells freshly released as clusters revealed that many cells appeared undamaged, and confocal microscopy of cells stained with propidium iodide showed an absence of fragmented nuclei. Taken together, this evidence suggests that apoptosis is not the cause of cell release. We conclude that cells are released from culture, not as a result of cell death, but via an active process suppressed by HCG.