Abstract: A processing vessel for isolating microvessel endothelial cells from liposuctioned fat tissues includes a fat-receiving basket defined by polyester screen material. Fat tissue removed from a patient by liposuction is received into the basket and is rinsed and digested with an enzymatic solution. The freed microvessel endothelial cells from the fat tissues are separated from the fat cells, and from blood cells and other materials which may be present in the basket by centrifuging. A bottom chamber of the processing vessel is configured to define a "pellet" of isolated endothelial cells which may be removed from the processing vessel for deposition on the inner lumenal surface of a synthetic graft which the fat-donor patient is to receive.