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The work in natural sciences locates between asking questions and answering them. Hereby, the question is an artwork and to answer it is a handicraft.

"Can the confrontation of adherent culture cells with artificial surfaces be prognosted, recorded, and manipulated? Can such a confrontation be exploited to communicate the scientists claims to a cell?"

Adressing this question requires to break it up into work packages. In the following the work packages are scheduled. By clicking on the icon You reach a page where every individual package will be explained more closely. As a beginning, go to the why?-page. Here the relevance of the question is illuminated.

The motivation to address the above question is simple. In nature cells are highly organized in tissue and organisms. They communicate extensively with the environment. In addition human artifacts like machines are orderly organized as well. Consequently it should be possible to combine both, the machine and the cell into a dialogue.

The micro-Contact Printing (µCP) offers the possibility to arrange cells and to modify their outer shape. This can influence the differentiation state of a single cell. In tissues, cells have both characteristic shapes and tissue specific differentiation states. Former, µCP with DNA can produce patterns from genetically altered cells.

In the Rational Surface Design (RSD) the contact patterns of cell under different conditions is analyzed with respect to characteristic geometry. The geometry parameters are used to imitate biologic conditions on artificial surfaces. The resulting surface patterns induce a cell state comparable to the one the geometry is taken from.

In the Cell Co-Culture (CCC) approach cells form the surface for other cells. This way the complex biochemistry of cell-conditioned surfaces is truly conserved. In a second step the surface deposits can be collected and used in µCP. The coculture of two different cell types induces a completely new cell behavior not accessible in conventional cell culture.

Besides contacting an artificial surface cells must be possible to detach from it. Detachment is more than disrupting a contact. Some special proteins are temporarily accumulated in detachment regions. They act as markers for the cell rear. It can be seen that cells always change front- and backside physiologically.

Cell traces are complex deposits of migrating cells. They where a cell came from. But also cell trace analysis gives information about the cell behavior during migration. The pattern of the trace is a result of the cell to surface contact pattern. Consequently cell trace patterns are modified when artificial surfaces successfully stimulate adherent cells.

In the Ultra-Violet Calcium Management (UVCM) cells' key signal compounds, calcium ions, are released inside a living heart muscle cell. In difference to the other methods here the environment is shortcut and the pure intracellular signalling remains. The resulting calcium oscillations resemble the behavior of the living heart in total.

In Total Internal Reflection Fluorescence (TIRF) microscopy the contact pattern between an adherent cell and the underlying substrate is imaged exclusively. This makes the method helpful in deriving pattern geometries and in testing artificially patterned surfaces. The contact pattern is like a fingerprint characteristic for different cell types and cell conditions.

Time Lapse Microscopy (TLM) shows cells being highly dynamic individuals. Also, the formation of ordered tissues and even organs like muscles is very dynamic. Cells keep their position over time but they always oscillate around their preferred loci. They explore the environment by touching it with protrusions. Migrators frequently change direction.

Scanning Acoustic Microscopy (SAM) does not use light but ultrasound to image migrating cells on surfaces. Here forces and the tension distribution inside cells can be seen. This gives information if a surface induces a strong cell adhesion. In addition an impression from tension distribution during migration shines up. Also the surface contacts are visible without artificial staining and toxic light irradiation.