Cell adhesion monitoring using a quartz crystal microbalance: comparative analysis of different mammalian cell lines

The quartz crystal microbalance (QCM) has been widely accepted as a sensiti ve technique to follow adsorption processes in gas as well as in liquid env ironments. However, there are only a few reports about the use of this tech nique to monitor the attachment and spreading of mammalian cells onto a sol id support in culture. Using a QCM-setup we investigated the time course of cell attachment and spreading as a function of seeding density for three w idespread and frequently used cell lines (MDCK strains I and II and Swiss 3 T3-fibroblasts). Results were found to be in good agreement with the geomet rical properties of the individual cell types. The shifts of the resonance frequency associated with confluent cell layers on top of the quartz resona tors were found to be dependent on the cell species [MDCK-I: (320+/-20) Hz; MDCK-II: (530+/-25) Hz; 3T3: (240+/-15) Hz] reflecting their individual in fluence on the sheer oscillation of the resonator. These findings are discu ssed with respect to the basic models of materials in contact with an oscil lating quartz resonator. We furthermore showed by inhibition-assays using s oluble RGD-related peptides, that only specific, integrin mediated cell adh esion is detected using this QCM approach, whereas the sole presence of the cellular body in close vicinity to the resonator surface is barely detecta ble.