Immunogen sequence: RSCDACMSSD LTFNCSWCHV LQRCSSGFDR YRQEWMDYGC AQEAEGRMCE DFQDEDHDSA SPDTSFSPYD GDLTTTSSSL FIDSLTTEDD TKLNPYAGGD GLQNNLSPKT KGTPVHLG. Recently, using SAGE (Serial Analysis of Gene Expression) technology, St. Croix et al, have identified