Table 1.

In vitro and ex vivo model benefits and limitations.

Model	Benefits	Limitations
Caco-2 (in vitro)	•Can be polarized •Cost-effective •Easy to use •Extensive literature available •Commercially available	•Cancerous origin •Long times to differentiate •Genetic drift
IPEC-J2—IPEC-1 (in vitro)	•Can be polarized •Commercially available •Good for studying the small intestine •Non-cancerous origin	•Not a suitable model for the colon
BIEC and FBCEC (in vitro)	•Good for studying bovine pathogens •Non-cancerous origin	•Not commercially available •Few papers available •Uncertain polarization capacity
Primary intestinal epithelial cell lines (in vitro)	•Can be polarized •Contain multiple cell types •Closer to an in vivo situation •Non-cancerous origin Physiologic relevance	•Not commercially available •Expensive maintenance •Short lifetime (weeks) •Needs to sacrifice animals to start a new culture
Organoids/enteroids (in vitro)	•Can be grown 2D or 3D •Can be polarized •Contain all epithelial cell types •Closer to an in vivo situation •Non-cancerous origin Physiologic relevance	•Not commercially available •Very expensive maintenance •Difficult to obtain and manage •Short lifetime (weeks) •Needs to sacrifice animals to start a new culture
Ussing chamber (ex-vivo)	•Tissue is polarized •Can obtain barrier function and transport data •Contain all epithelial cell types •Physiologic relevance	•Short lifetime (<5 h) •Require expensive equipment and knowledge •Needs to sacrifice animals
Everted intestinal ring	•Absence of maintenance •Closest to in-vivo situation •Contain all epithelial cell types	•Short lifetime (<3 h) •Needs to sacrifice animals •Muscularis mucosa and lamina propria presence
InTESTine™	•Tissue is polarized •Can obtain barrier function and transport data •Physiologic relevance •Contain all epithelial cell types •Cheaper than Ussing chamber	•Short lifetime •Needs to sacrifice animals