Figure 1.

Schematic illustration of in vitro human organ models for COVID‐19 research. COVID‐19, caused by SARS‐CoV‐2 virus, clinically presents a wide spectrum of symptoms, such as fever, pneumonia, abnormal pain, and coaulopathy involving different organs. Organoids are 3D multicellular clusters derived from human stem cells (e.g., ASCs and PSCs) by self‐organization, resembling native tissues. Organ‐on‐a‐chip is a bioengineered microfluidic cell culture device that can mimic cellular microenvironment (e.g., fluid flow, stretch, and tissue interface), recapitulating the functional units of human organs. These two physiologically relevant tissue/organ model systems can be used to study SARS‐CoV‐2 pathogenesis and human‐relevant responses, facilitating their potential applications in disease modeling, drug/vaccine development, immune responses, virus transmission, host‐virus interactions, and personalized therapy.