High throughput multiwell system for culturing 3D tissue constructs in-vitro or in-vivo, method for producing said multiwell system and methods for preparing 3D tissue constructs from cells using said multiwell system

1. A method for preparing a 3D tissue construct from cells comprising the steps of:

a) introducing a medium comprising cells in a well of a multiwell system,

wherein the multiwell system comprises at least 3 wells, the wells comprises sidewalls made of alginate, polylactic acid or PEOT/PBT, wherein said wells have a volume between 0.125 and 4.0 mm 3 , a wall thickness of at least 50 microns and a closed bottom, wherein the multiwell system does not comprise a 3D synthetic polymer scaffold and the initial number of cells per well is between 4,000 and 25,000; and

b) culturing the cells to obtain a 3D tissue construct.

2. The method according to claim 1 , wherein the wells have an inner diameter larger than 0.5 mm.

3. The method according to claim 1 , wherein the cells are stem cells, preferably human Mesenchymal Stem Cells (hMSC), or chondrocytes.

4. The method according to claim 1 , wherein the cells are of a first type of cells and wherein cells of a second type are introduced in the well and cocultured with the cells of the first cell type in step b, wherein the cells of the second type stimulate the growth of cells of the first type in the formation of said 3D tissue construct.

5. The method according to claim 1 , wherein 3D tissue constructs are formed in 2 or more wells of the multiwell system and wherein different culturing conditions are applied to the 2 or more wells.

6. The method according to claim 5 , wherein the multiwell system is implanted in a pocket of a suitable animal.

7. A method for producing a multiwell system for use for preparing a 3D tissue construct from cells, comprising steps of:

a) melting alginate, polylactic acid, or PEOT/PBT in a thermal jacket;

b) extruding the melted alginate, polylactic acid, or PEOT/PBT under pressure through a nozzle to form a plotted fiber;

c) repeating step b), thereby depositing a subsequent plotted fiber in parallel at a distance of between 0.125 and 2.0 mm next to the last deposited fiber until a layer of alginate, polylactic acid, or PEOT/PBT is formed;

d) depositing a subsequent layer on the previous layer, wherein the fibers forming said subsequent layer are deposited at an angle preferably between 10 and 90 degrees relative to the fibers of the previous layer; and

e) repeating step d) until a desired height is achieved;

wherein the method produces a multiwell system comprising at least 3 wells, the wells comprise sidewalls made of alginate, polylactic acid or PEOT/PBT, wherein said wells have a volume between 0.125 and 4.0 mm 3 , a wall thickness of at least 50 microns and a closed bottom, and wherein the multiwell system does not comprise a 3D synthetic polymer scaffold.

8. A multiwell system comprising at least 3 wells, wherein the wells comprise sidewalls made of alginate, polylactic acid or PEOT/PBT, wherein said wells have a volume between 0.125 and 4.0 mm 3 , a wall thickness of at least 50 microns and a closed bottom, and wherein the multiwell system does not comprise a 3D synthetic polymer scaffold.

9. The multiwell system according to claim 8 , wherein said alginate, polylactic acid or PEOT/PBT has been approved for use in an animal by a legal authority.