Chamber of a bioreactor platform

Disclosed herein is mesoscale bioreactor platform comprising an upwards open chamber for a biological cell, which chamber via a first port is in communication with a first channel for conducting an influent stream of a liquid into the chamber and via a second port is in communication with a second channel for conducting an effluent stream of a liquid away from the chamber, which chamber is provided with a closure comprising a water-immiscible liquid, and wherein said first channel is in fluid communication with a reservoir for a liquid and said second channel is in fluid communication with a waste container. Furthermore, a method for modifying the interaction of a content of a chamber with the surroundings is described as well as method of culturing a biological cell.