Immunogen sequence: EELPGQSFDN KGYFCGEETM PVYESVFMED GETTRKIALE TERPPQVEVH VWTIRKGILQ HFHIEKISKR MFEELPHFKL VTRTTLSQWK IFTEGEAQIS QMCSSRVCRT EL Highest antigen sequence identity to the following orthologs: Mouse - 88%, Rat - 83%. CHRDL1 is an antagonist