The activities of peptides “31–43”, “44–55” and “56–68” of A-gliadin on In Vitro Cultures of CaCo-2 Cells
Claudio Giovannini, Roberto Luchetti and Massimo De Vincenzi
In previous studies, various A-gliadin peptides with known amino acid sequences have been tested for their damaging effects on in vitro cultured atrophic coeliac mucosa. The largest common sequences among the in vitro toxic peptides were (gln)3-pro and pro-ser-(gln)2. Three of these active A-gliadin fragments were synthesised and characterised, namely, the peptides corresponding to the amino acid sequences “31–43” and “44–55”, which contain the sequences (gln)3-pro and pro-ser-(gln)2, respectively, and the “56–68” fragment lacking both active amino acid sequences. While the “56–68” A-gliadin peptide was completely inactive in CaCo-2 cells, the other two peptides were cytotoxic toward these cells to different extents. Our results confirm that CaCo-2 cells are a suitable model for the identification of toxic peptides responsible for coeliac pathogenesis.