Immunogen sequence: VKFLSYNSGN EEELSGNPGY QLGKPVRALN INRMNNVTTL HLWQSAGRGL CTSATFKPIL FGENVLSGCL LEVGINENCT QLRENAVERL DSLIQATHVA MRGNSDYADL SDGWLEIIRV DAPDPGADPL ASSVNGMCLD IPAHLSIRIL ISDAGAVEGI TQQEILGVET RFSSVNWQYQ CGLTCEHKAD LLPISASVQF IKIPAQLPHP LTR