动物造模,肺结核杆菌模型 z-bio 2021-04-06 661

　　(1) Replication method Culture human tuberculosis in modified Roche medium for 2 to 3 weeks, collect well-growing cultures, and use 5 mg/ml (0.05% Tween) homogeneous bacterial suspension in an agate mortar (Including) Crush 0.8 ml of sterile saline solution) and 0.2 ml (approximately 10,000,000 CFU) were injected into the tail vein of each mouse. In the process of observing the infection of model animals, bacteria were regularly isolated and cultured. The animals were slaughtered, tissues and organs were collected, fixed with 10% formaldehyde solution under a microscope, and normal tissue sections were prepared and stained with HE. , And observe under an optical microscope.

　　(2) Model characteristics Microscopic examination and organ smear culture showed that myocardium, pericardium, aortic trunk, coronary artery, liver, spleen, lung, kidney and lymph nodes may all carry Mycobacterium tuberculosis. . Microscopic pathology shows that the pericardium is mainly infiltrated by lymphocytes and monocytes; the main feature of myocardium is the short division and dissolution of muscle fibers and the accumulation of lymphocytes and monocytes. The inner wall of the aortic trunk is irregular. As more lymphocytes and monocytes accumulate, inflammation becomes more common. The liver, spleen and kidneys were necrotic, and the brain showed inflammation caused by lymphocyte infiltration. BCG immunohistochemical staining can detect BCG positivity in the organs of model animals. Under the electron microscope, the mitochondria were obviously swollen, arranged randomly, and the muscle fibers were dissolved and the basement membrane was visible. Tuberculosis infection experiments conducted in mice of various strains showed that NIH and BALB/c are not sensitive to tuberculosis, and there is a big gender difference between 615 and TA1 mice. Although TA2 and DBA/2 are sensitive to tuberculosis, the content of Mycobacterium tuberculosis per gram of organ is significantly lower than that of C57BL/6N and KM mice.

　　(3) Drug comparison After infection with Mycobacterium tuberculosis, only a few people will cause acute disease progression. Most people will form an effective immune response to prevent the onset of the disease, and may have latent infection without clinical symptoms, and symptoms may last for several years. Years or even decades. When the body's resistance is reduced or glucocorticoids are used, this potential infection can be reactivated and form an active disease. The latent infection model was initially established by a small amount of Mycobacterium tuberculosis infection, but after bacterial infection, the model was established using anti-tuberculosis drugs. The establishment of the model includes many parameters, such as the number of infected bacteria, the route of infection, the start time of anti-tuberculosis drug treatment, drug dosage, treatment time, stop time, and the time interval between the two ends. Tuberculosis treatment and immune intervention. This model does not yet fully reflect all the clinical manifestations of human tuberculosis, but it is an important tool for studying latent Mycobacterium tuberculosis infection. You can simulate the onset of human diseases to varying degrees. To study the physiological characteristics and immune mechanism of Mycobacterium tuberculosis under latent infection, explain the occurrence of latent infection and provide pathogenic substances, and provide the basis for new drug screening and vaccine screening as well as the treatment of MTB latent infection.