用In－111通过1B4M－DTPA标记单克隆抗体的研究

study on Labeling Monoclonal Antibody with In-111 via 1B4M-DTPA

研究了双功能联接剂１－（４－异硫氰基苄基）－４－甲基二乙三胺五乙酸（１Ｂ４Ｍ－ＤＴＰＡ）与抗体偶联反应以及用Ｉｎ－１１１标记偶联物的条件，得到了体内外稳定的Ｉｎ－１１１标记抗体；用高纯Ｉｎ－１１１通过１Ｂ４Ｍ－ＤＴＰＡ标记了抗胃癌单抗３Ｈ１１，标记抗体免疫活性保持完好，放射性比活度为２．０×１０￣（１１）Ｂｑ／ｇ；荷瘤裸鼠注射标记物２４ｈ后，即得到靶目标的清晰显像，１６８ｈ的瘤／肝放射性比值为２．０。

Optimal chemical conditions for the conjugation reaction of MoAb with a new bifunctional chelate ligand 1-(4-isothiocyanatobenzyl)-4-methyl-diethylenetri-aminepentaacetic acid and subsequent In-111 labeling were studied. The In-111-1B4M-DTPA-IgG labels were stable both in vitro and in vivo.The MoAbs 3H11 were labeled with highly pure In-111 through 1B4M-DTPA without loss of the im-munoreactivity.The In-111 labeled MoAbs 3H11 were examined with nude mice bearing human gastro-tumor xenograft.At 24h,post-injection of the In-111 labels,a clear tumor scintigraph was obtained.