Table 2.

Advantages and Drawbacks of Organoids to Study Helminth–Host Interactions

Advantages	Disadvantages
Experimental
•When compared with cell lines, organoids display the different cell types present in the organ of origin and self-organize. This allows a better understanding of the molecular and cellular interactions of helminths with their host. •Multicellularity permits study of the role of different cell types in helminth invasion and colonization, host damage and responses. Moreover, up- and downregulation of cell populations and factors in tissue-specific context can be evaluated after exposure to helminths and their products. •3D organoids reproduce tissue architecture to a certain extent. •2D organoids allow ready apical delivery of parasites and their products and better control of the conditions of co-culture with helminths. •Both ES products and larval stages can be co-cultured with organoids.	•Heterogeneity of organoids (in size, architecture, metabolism, and differentiation of cells, across samples) can impact the observations upon co-culture with helminths and their products. •In vivo tissue architecture is not completely recapitulated in organoids. •2D organoids lack the cellular architecture present in 3D organoids and in vivo situations. •Organoids are still reductionist models lacking more complex interactions regulating infection in the native microenvironment. •Dimensional conformation and size of organoids impacts the delivery and co-culture of specific parasitic stages. •Moulting of helminth parasites in organoid culture may be restricted by the lifespan of the organoids and their passage requirements (3D organoids).
Technical
•Organoid lines can be generated from small tissue biopsies from the specific host and can be shared across different laboratories. •Indefinite expansion and cryopreservation of individual organoid lines with genomic stability. •Organoids can be genetically engineered by lentiviral expression systems and CRISPR/Cas9. •2D organoid systems are amenable to high-throughput applications.	•Organoid culture is costly and there is an initial requirement to access tissue from animals or patients, which has ethical implications.