Immunogen sequence: CGDQLCVWGH CTKMATRGSN GTICDNQRDC QPGLCCAFQR GLLFPVCTPL PVEGELCHDP ASRLLDLITW ELEPDGALDR CPCASGLLCQ PHSHSLVYVC KPTFVGSRDQ DGEILLPREV PDEYLAASW. DKK3, like DKK1, DKK2, and DKK4, possesses an N-terminal signal peptide and 2 conserved cys