Immunogen sequence: LQFPILNASV DENCQNITYK ASHNIGIAMD TEQGLIVPNV KNVQICSIFD IATELNRLQK LGSVGQLSTT DLTGGTFTLS NIGSIGGTFA KPVIMPPEVA IGA Highest antigen sequence identity to the following orthologs: Mouse - 90%, Rat - 90%. The branched-chain alpha-keto acid