The invention relates to a polypeptide including or consisting of SEQ ID NO: 1, or a sequence at least 80% identical to SEQ ID NO: 1, or a sequence of at least 4 consecutive amino acids included in SEQ ID NO: 1, wherein said polypeptide has at least one effect selected from: inducing the expression and/or the secretion of at least one gastrointestinal mucin； and inducing the expression and/or the secretion of at least one intestinal defense molecule expressed by Paneth cells； and inducing an increase in the population of mucus cells and/or in the population of Paneth cells, with the proviso that the polypeptide does not include the SEQ ID NO: 2 sequence.
