风湿性关节炎,RA,动物造模 z-bo 2022-04-25 619

　　(1) Human tumor necrosis factor transgenic mouse model [Modeling mechanism] Tumor necrosis factor-α (TNF-α) is mainly secreted from activated macrophages, activated T cells, NK cells and mast cells. It also secretes a small amount. TNF-α specific membrane receptors are present in almost all cell types. TNF was originally found to be related to tumors, and is now apparently an immunomodulator of normal and chronic inflammation. It was found that the levels of TNF-α, IL-1 and IL-6 in the synovial fluid of patient A increased. This indicates that the cause of RA is related to TNF-α. The expression of human TNF-α gene in mice can partially mimic the clinical manifestations of RA. [Modeling method] Recombinant TNF-globin recombinant DNA fragment, which contains the complete human TNF-α gene and the 5'end 0.6kb sequence, and is polyadenylated with the 3'untranslated region of the human β globin gene Site reorganization. application form. This modification provides the required polyadenylation signal and does not interfere with the normal translation of wild-type human TNF. Recombinant DNA fragments were microinjected into (CBA x C57B1/6) F1 mouse fertilized eggs, and screened in the first established mouse, and then the RA transgenic mouse model was obtained.

　　[Characteristics of the model] The main clinical symptoms of this model are ankle joint swelling and movement disorders, which are 100% inherited from the next generation. When the ankle joint swells, the onset is obvious at 3-4 weeks of age, at which time synovial hyperplasia is observed. Before 5 weeks of age, the ankle joint was swollen and the endoscopic synovial membrane was obviously hyperplastic and inflamed. At 9-10 weeks of age, limb dyskinesia occurs and hind limb movement disappears completely. Weight loss is a common feature of these mice. Histopathological examination showed bilateral symmetrical polyarthritis, synovial hyperplasia after 3 weeks of age, polymorphonuclear and lymphoid infiltration of various joints in the synovial cavity at different developmental stages. The facts proved very clear. In addition, in humans, vascular neurogenesis, articular cartilage destruction and fibrotic tissue formation are very similar to RA. However, no rheumatoid factor or rheumatoid nodules were found in the serum of all stages of the disease in this model mouse. This is different from human RA. [Model Evaluation and Application] The TNF model can be used to study the pathogenesis of rheumatoid arthritis, autoimmune pathology and the pharmacodynamics of rheumatoid arthritis drugs. (2) Human IgGFc receptor transgenic RA mouse model [Modeling mechanism] Human FCGR2A gene encodes IgGFc receptor. The human FCGR2A gene was introduced into mice. It encodes the human FcgRIIAR131 gene product and can bind to mouse IgG. Combinations of different subcategories. The mice in this strain express human FCGR2A on platelets and macrophages, and the expression level is equivalent to that of humans. [Modeling method] A 72kb DNA fragment was screened from the human P1 genome library by PCR. The FCGR2A gene is 20 kb, the 5'flanking region containing the promoter is 45 kb, and the 3'flanking region is 7 kb. DNA fragments were microinjected to generate transgenic mice, and the foreign genes were randomly integrated into the mouse genome.