A plant agglutinin was isolated and purified from Croton tiglium beans by DEAE- sephadex and gel – filtration chromatographies. The agglutinin had a molecular weight of 220,000 and was named Croton tiglium agglutinin 220 (CTA220). It had specific affinity to rabbit erythrocytes. However, it did not agglutinate pig erythrocytes. CTA220 was inhibited by L-fucose whereas RCA120, RCA60 (Ricinus communis agglutinins of molecular weights 120,000 and 60,000 respectively) and APA134 (Abrus precatorius agglutinin with molecular weight 134,000) were inhibited by galactose. Like RCA120, RCA60 and APA134 CTA220 had no hemolytic activity. 經由DEAE- sephadex及gel – filtration柱層層析法，而從Croton tiglium 中分離出一種植物凝集素。此凝集素分子量為220,000，故簡稱為CTA220。
CTA220對紅血球絕無溶血作用，而對兔子紅血球有強烈凝集作用，然對豬的紅血球則無此凝集反應。
CTA220的凝集作用可被L-fucose抑制。
