The present invention is directed to a method to expand adherent cells comprising addition of adherent cells to an expansion container comprising microcarriers and culture medium; removing medium from the expansion container through a 8-20 mm filter; allowing cells to attach to microcarriers and keeping the expansion container in motion with an angle of between 30 to 90° and −30 to −90°. The present invention is also directed to a device suitable in the method. The advantage of the present invention is that fewer steps are needed to expand adherent cells, including stem cells like MSC opening the way for the use of autologeous and allogenous stem cell therapy. In addition, contamination risk is limited since the present invention may be carried out in a closed, disposable system.