Immunogen sequence: MAETLEFNDV YQEVKGSMND GRLRLSRQGI IFKNSKTGKV DNIQAGELTE GIWRRVALGH GLKLLTKNGH VYKYDGFRES EFEKLSDFFK THYRLELMEK DLCVKGWNWG TVKFGGQLLS FDIGDQPVFE IPLSNVSQCT TGKNEVTLEF HQNDDAEVSL MEVRFYVPPT QEDGVDPVEA FAQNVLSKAD VIQATGDAIC IFRELQCLTP RGR