含对硝基苯丙氨酸的B淋巴细胞刺激因子疫苗对狼疮肾炎模型小鼠的保护作用

考察含对硝基苯丙氨酸的B淋巴细胞刺激因子(BAFF)治疗BAFF过表达的自身免疫性疾病的效果。利用本研究前期构建的工程菌，表达纯化了B淋巴细胞刺激因子的可溶型突变体(smBAFF)以及在其65位定点引入了对硝基苯丙氨酸的改构体(pNO₂Phe⁶⁵smBAFF)。通过考察pNO₂Phe⁶⁵smBAFF体外促小鼠淋巴细胞增殖活性、免疫原性以及所诱导的抗血清对天然BAFF活性的抑制作用，评价了其用于治疗BAFF过表达的自身免疫性疾病的可行性；同时采用了cGVHD(graft-versus-host disease)诱导的狼疮肾炎小鼠模型评价了pNO₂Phe⁶⁵smBAFF的药理活性。结果表明:定点引入了对硝基苯丙氨酸的pNO₂Phe⁶⁵smBAFF不具有促进小鼠淋巴细胞增殖的能力；由于对硝基苯丙氨酸的引入显著增强了蛋白的免疫原性，诱导机体产生了可以抑制天然BAFF活性的交叉抗体；在cGVHD诱导的狼疮肾炎小鼠模型中，pNO₂Phe⁶⁵smBAFF可显著减轻疾病症状。定点引入了对硝基苯丙氨酸的pNO₂Phe⁶⁵smBAFF可以作为治疗BAFF过表达的自身免疫性疾病的候选分子。

Protective effects of p-nitrophenylalanine-containing BAFF vaccine on lupus nephritis model mice

In order to verify whether p-nitrophenylalanine-containing BAFF vaccine can be used as a candidate molecule for the treatment of autoimmune diseases with BAFF over-expression, a soluble mutant of B cell activating factor belonging to the TNF Family(smBAFF)and its pNO₂Phe mutant(pNO₂Phe⁶⁵smBAFF), which site specific incorporated pNO₂Phe at position 65 of smBAFF, were expressed and purified. In order to evaluate the feasibility of using pNO₂Phe⁶⁵smBAFF to treat BAFF-over-expressed autoimmune diseases, we investigate its Lymphocyte-stimulating capacity, immunogenicity and inhibitory effect of serum on biological activity of natural BAFF. The pharmacological activity of pNO₂Phe⁶⁵smBAFF was evaluated using a cGVHD(graft-versus-host disease)induced SLE mouse model. Results indicated that pNO₂Phe⁶⁵smBAFF, could bind to mouse lymphocytes but could not promote the proliferation of mouse lymphocytes. Moreover, the incorporation of pNO₂Phe significantly increased the immunogenicity and induced cross-antibody, which can inhibit the biological activity of natural BAFF. In cGVHD induced SLE mouse model, pNO₂Phe⁶⁵smBAFF can significantly reduce the symptoms of the disease and play a therapeutic role. Therefore, pNO₂Phe⁶⁵smBAFF can be used as a candidate molecule for the treatment of autoimmune diseases with BAFF over-expression.