CAMP is a member of an antimicrobial peptide family, characterized by a highly conserved N-terminal signal peptide containing a cathelin domain and a structurally variable cationic antimicrobial peptide, which is produced by extracellular proteolysis from the C-terminus. The protein has several functions in addition to antimicrobial activity, including cell chemotaxis, immune mediator induction and inflammatory response regulation. Recombinant human CAMP protein, fused to His-tag at N-terminus, was expressed in E.coli.