In case you want to multiply cells, do not read any further information, because perfect conventional methods are available for your purpose.

However, if you want to generate functional, thus highly differentiated tissues then the following new information may be the basis for your future work.

The per(i)fusion culture system presented here makes experiments possible, which failed by conventional methods. Advantages are:

- Selection from a variety of cell supports

- Individual influence on differentiation

- Per(i)fusion of culture medium

- Culture of epithelia in a natural gradient

- Microscopical observation

- Long term culture for chronical toxicity

- Tissue engineering for surgical implantation

- Testing of biomaterials

We show a new strategy to generate differentiated tissues. All of our tools for tissue engineering were designed and constructed arising out of experimental necessities and professional experience.