Conceptual drawing of an organ-chip cartridge that includes a PC and µCA for both the microvascular and interstitial compartments of a single OoC or HoC. On the left are the inputs to the organ, and on the right are outputs, including an online MS if desired. The vertical arrows access the secondary space of the organ (interstitial, bronchial, biliary, urinary, etc.). Interconnected cartridges would comprise an instrumented mHu or µHu system, either in series as shown for selected organs or in parallel as in Fig. 1.