The Cell-free Protein Synthesis Unit is engaged in the synthesis of recombinant proteins in various cell-free systems. Special focus is on the characterisation, modification and functional examination of cell-free manufactured antibody formats. In order to analyse proteins, they must first be provided in a functionally active form. The expression of proteins in living cells, i.e. in vivo, is frequently used but does not always lead to the desired goal, since not every protein in cell cultures can be satisfactorily synthesized. An efficient alternative to the expression of proteins in living cells is cell-free protein synthesis. In this procedure, the constituents of the cell are used to produce a certain target protein in a rapid and cost-effective manner. A special advantage of using eukaryotic cell lysates is that they permit the synthesis of proteins with post-translational modifications (PTMs).