球形纤维素固定化DNA制备免疫吸附剂

以球形纤维素为载体,经环氧氯丙烷活化后共价键联小牛胸腺DNA,制备DNA免疫吸附剂,通过血液灌流能够治疗系统性红斑狼疮.对病人血清的吸附实验结果表明,每毫升吸附剂与3mL病人血清混合,于37℃保温1 h,可吸附除去40%～70%致病抗体

Coupling of DNA to Bead Type Cellulose as Immunoadsorbent

In order to remove the anti DNAantibody from the blood of patients with systematic lupus erythematosus(SLE), DNAimmunoadsorbent was prepared by coupling calf thymus DNAto epichlorohydrin activated cellulose beads.The methods and conditions for activation of carrier beads, DNAcoupling and adsorption with patient's plasma were investigated.The activation level was found to be dependent on the NaOHconcentration, amount of offered epichlorohydrin and the molar ratio between NaOHand epichlorohydrin.One milliliter of cellulose beads was activated by incubation with0.5 mLof epichlorohydrin and2.0 mLof2.0-3.0 mol/L NaOHsolution at40 ℃ for2 h, and the activation level was60_100 μmol/mLbeads.DNAcoupling was found to be strongly dependent on temperature and pH.The optimal coupling conditions were0.1 mol/L Tris HCl buffer, pH7.9-8.0 and70-90 ℃. High activation level, high DNAconcentration and long reaction time were also required.Under the optimal condition, 2.0-3.0 mg of DNAcould be coupled to1.0 mLof cellulose beads.In vitro adsorption tests showed that incubation of1.0 mLof adsorbent with3.0 mLof plasma could remove40%-70% of anti DNAantibody from the plasma