Comparison of Lectin from Pseudixus japonicus and Concanavalin a on Lymphocytes Proliferation and Cytotoxicity

Pseudixus japonicus agglutinin (PJA) was isolated. And its characteristics were compared with those of concanavalin A (Con A). PJA is a glycopritein composed of 49.3% carbohydrate and 50.7% protein which had relatively high percentages of glutamic acid, aspartic acid and phenylalanine residues. The hemagglutinating activity of PJA was approximately one-eighth of that of Con A when tested with mouse crythrocytes. PJA failed to simulate the proliferation or transformation of human and mouse lymphocytes in contratst to Con A. PJA and Con A showed cytotoxicities against SNU-1 (human stomach cancer cells), SNU-CI (human colon cancer cells) and mouse Sarcoma 180 cells when tested by 3-(4, 5-dimethyl thiazol-2-yl)2. 5-diphenyl tetrazolium bromide (MIT) colorimetric assay. The antitumor activity of the lectin in vivo was also tested in Sarcoma 180 bearing mice. There was no significant difference in prologation of lifc span of the mice after the treatment with PJA and Con A for 10 consecutive days.