Table 1.

Genes encoding molecular markers of the Caco-2/HT29 barrier, and analysed by RT-qPCR

Gene Identification	Encoded protein name	Function
ALPI	Intestinal alkaline phosphatase	Digestive brush-border enzyme. Detoxification of lipopolysaccharides
SI	Sucrase-isomaltase	Digestion of dietary carbohydrates including starch, sucrase and isomaltase
SLC15A1	Solute carrier family 15 member 1	Intestinal hydrogen peptide cotransporter. Uptake of di- and tri-peptides from the lumen and into enterocytes
ZO-1	Zonula occludens-1	Tight junction adaptor protein that also regulates adherent junctions.
OCLN	Occludin	Integral membrane protein. Required for cytokine-induced regulation of the tight junction paracellular permeability barrier.
CLDN2	Claudin-2	Claudin proteins are identified as major integral membrane proteins, localized exclusively at tight junctions in the intestine.