[Cell culture as a prescreening system for drug prevention of restenosis?]

Migration and proliferation of smooth muscle cells (SMC) from the media into the subendothelial space are important steps in the development of restenosing events after angioplasty; therefore a medical inhibition of this activity seems to be of clinical interest. Primary stenosing plaque material of 20 patients and restenosing plaque material of 6 patients was removed by atherectomy (Prof. Höfling, Dr. Bauriedel, Munich). For the isolation of plaque cells a mixture of Collagenase/Elastase was used. The vast majority of plaque cells was identified as smooth muscle cells by positive reaction with monoclonal antibodies against smooth muscle alpha-Actin. Propranolol (10(-4) mol/l to 10(-9) mol/l), Prednisolone (10(-3) mol/l to 10(-8) mol/l) and Etoposide (10(-4) mol/l to 10(-9) mol/l) were added to the cultures one day after seeding. After 3 days cell number and cell size distribution were analysed in a cell counter (Casy I, Schärfe System, Reutlingen). While Propranolol didn't change proliferative activity of SMC, Prednisolone caused a slight, but dose dependent inhibition of SMC-proliferation. Etoposid inhibited SMC-proliferation even below clinical concentrations to 50%. The local application of steroid or cytostatic agents might improve long term results after angioplasty. The clinical relevance of this 'Prescreening System' has to be evaluated by experimental and clinical studies.