Citrullinated LL-37 1cit is a citrullinated LL-37 peptide. Citrullinated LL-37 1cit does not alter the antiviral effect of LL-37 toward human rhinovirus.Citrullinated LL-37 1cit shows antibacterial activity toward S. aureus. Citrullinated LL-37 1cit causes a reduction in the levels of IL-8 , CCL5, and IL-6 mRNA induced by RV1B.