Cell Visualization System for Multi-Layer Cell Culture Device

A multi-layer cell culture device comprising:

• at least two cell culture chambers, each cell culture chamber having a gas permeable, liquid impermeable membrane forming a bottom surface, side walls and an opposing plate forming a top surface, wherein the gas permeable, liquid impermeable membrane forming a bottom surface and the opposing plate are sealed to side walls to form cell culture chambers, wherein the opposing plate has a top side and the top side of the opposing plate has bumps, wherein each cell culture chamber is adjacent to a tracheal space;
• and,
• a bottom plate comprising a bottom side having support ribs having a depth “d” and a top side having bumps;
• wherein the gas permeable, liquid impermeable membrane of each cell culture chamber rests on the bumps on the top side of an opposing plate of an adjacent cell culture chamber or the bottom plate;
• wherein the bottom plate further comprises at least one window between support ribs;
• and wherein the top side of the bottom plate opposite the at least one window is free of bumps.