亲和层析纯化的特异性免疫球蛋白及其片段对VX中毒的保护作用

用Ｓｅｐｈａｒｏｓｅ４Ｂ－６－氨基己酰－氨基ＶＸ亲和凝胶层析分离纯化兔抗ＶＸ抗血清中对ＶＸ特异的免疫球蛋白（Ｉｇｓ），再用胃蛋白酶裂解为Ｆ（ａｂ）２片段．用酶联免疫吸附试验法测定抗体活性，在吸光度１．０（４９２ｎｍ）时，抗血清，Ｉｇｓ和Ｆ（ａｂ）２的蛋白质浓度分别是１．７５，０．２５和０．１７ｍｇ·Ｌ－１．在试管内保护电鳐乙酰胆碱酯酶活性５０％所需的浓度，Ｉｇｓ和Ｆ（ａｂ）２只需抗血清的２．６％和３．８％．ｉｖ抗血清，Ｉｇｓ和风Ｆ（ａｂ）２对抗小鼠１×ＬＤ９５ＶＸ中毒死亡的最小全保护剂量分别为每鼠７００，３２和３７μｇ，在此剂量下对小鼠脑胆碱酯酶活性的保护申分别为６４％，６７％和７６％．

Protective effect of affinity chromatography purified specific immunoglobulins and their fragments against VX intoxication

A rabbit anti-VX antiserum was pur-ified byaffinity chromatography with a Scpharose4B-6-aminohexanoyl-amino-VX column.Purifiedimmunoglobulins (Igs)were cleavaged by pepsin to pro-duce F(ab)2fragments.At A492nm=1(immunologicalreactivity measured by ELISA),the protein concentra-tions of antiserum,Igs and F(ab)2were 1.75、0.25 and0.17 mg* L-1 ,respectively In in vitro test、the proteinconcentrations of Igs and F(ab)2 required for pro-tecting 50% Torpedo AChE activity against VX inhibi-tion were 2.6% and 3.8% of that of antiserum. Theminimal doses of antiserum, Igs and F(ab)2 for fullprotection against 1× LD95 VX intoxication were 700,32 and 37μg per mouse, respectively. At this doselevel,antiserum,Igs and F(ab)2 protected brain ChEactivity against VX inhibition by 64%,67% and 76%.