upon removing the cells from a low density monolayer culture system and permitting the cells to form aggregates in suspension , we observed a change of several physical and biochemical parameters : ( a ) reduction in average cell volume , ( b ) blockage and accumulation of cells in g1 , ( c ) rise in secreted protease activity , ( d ) rise in acetylcholinesterase and choline acetyltransferase activities , and ( e ) disappearance of embryonic antigen f9 .
C0007634
cells
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secreted