Fig. 1: Complexity of current models available for the study of human infectious diseases.
From: Organoids as host models for infection biology – a review of methods

Cell lines are widely accessible and practical but lack epithelial complexity. Organoids and organoid-derived primary cell monolayers consist of primary nontransformed cells that can differentiate into different cell types. Animal models allow the study of host–pathogen interactions in whole organisms; however, pathogens are often highly adapted to their natural host, and thus animal studies have limitations in the study of human infectious diseases.