动物造模,药效评价,肺炎衣原体肺炎 z-bio 2024-07-09 429

　　1. Animal modeling materials: ICR male mice with an age of about 2 months from distant mating, with an average weight of 25g; Medication: Chlamydia pneumoniae strain CWL-029, ether, 2SP buffer.

　　2. Modeling method: The CWL-029 strain of Chlamydia pneumoniae was propagated in HEp-2 cell culture medium. Infected cells were collected using sterile glass beads, destroyed by ultrasound, and purified by centrifugation at low and high speeds for one cycle. They were suspended in 2SP sterile buffer at a concentration of 1.12 × 10 octagonal inclusion body forming units (IFUs)/ml. Divide each 0.5ml into several portions. Store at -70 ℃.

　　Inoculate mice with pathogen suspension or 2SP buffer via nasal route. Inhalate mild anesthetized mice with ether first to induce excessive ventilation for intranasal administration. Each mouse was injected several drops (0.05ml) of inoculum into their nostrils using a syringe with a fourth and a half needle during the inhalation phase. Each mouse in the experimental group was administered approximately 7.0 x 1000000 IFU of Chlamydia pneumoniae. The control group was infused with 2SP buffer solution using the same method.

　　3. Modeling principle: Chlamydia pneumoniae causes pneumonia.

　　4. Changes after modeling: The symptoms of mice inoculated with Chlamydia pneumoniae are usually mild. Within 3 days after inoculation, there is a decrease in animal vitality, reduced food and water consumption, and wrinkled hair. Usually, it returns to normal after about 1 week. Dead animals show a significant decrease in activity and food consumption after vaccination, until death. The control group mice showed no significant abnormal symptoms.

　　On the first day after vaccination, the lungs of the mice in the modeling group showed significant congestion and patchy consolidation; On the third day, the most severe congestion change occurred, and the range of consolidation expanded, with a few animals with more severe lesions showing patchy bleeding; On the 7th day, the consolidation was most obvious, while congestion gradually decreased. This change lasted until the 21st day. Afterwards, lung consolidation gradually decreased, and by the 28th and 60th days, only some mice showed slight congestion and consolidation changes. On the third day after vaccination, the control group mice showed mild and uniform congestion changes, and no significant abnormal changes were observed after three weeks.

　　After vaccination, the mice in the modeling group mainly exhibited irregularly distributed interstitial pneumonia, with the most obvious symptoms observed on the 3rd to 7th day. On the first day, all animals showed varying degrees of interstitial pneumonia changes, with the area of lung consolidation reaching 25% to 50%. The alveolar walls were congested, accompanied by significant infiltration of neutrophils. There is a large amount of inflammatory exudation in the alveolar cavity, and a large amount of neutrophil infiltration can be seen around the bronchi. Scattered foam cells can be seen in inflammatory cells of a few animals. The changes on the third day are similar to those on the first day, but interstitial pneumonia is more pronounced. The difference is that scattered or small focal foam cell reaction foci can be seen in the stroma, and small focal lymphocyte aggregation begins around bronchioles and small vessels. On the 7th day, it still showed interstitial pneumonia and focal pneumonia, with a reduced consolidation area ranging from 15% to 50%. The degree of alveolar exudation and neutrophil infiltration were also reduced. But all animals showed focal distribution of lymphocytes and monocytes around the bronchi and blood vessels. Focal accumulation of foam cells can be seen in the alveolar cavity and on the alveolar wall, and occasional hyperplasia of alveolar epithelial cells can be seen, with cytoplasm showing foam cell like changes. On the 14th day, both interstitial pneumonia and focal pneumonia were significantly relieved, with focal pneumonia being the main type. Neutrophil infiltration was still predominant in the lesion, accompanied by varying amounts of lymphocytes and monocytes. Foam cells also decreased, but there were still small foci or scattered distribution. After 21 days, the lung inflammation was lighter, and there was a small amount of neutrophil infiltration in the focus. Scattered lymphocytes and monocytes were seen, and occasionally foam cells were seen. But focal lymphocyte accumulation can be seen around the bronchi. On the 28th day, the lung changes were close to normal, with mild congestion of the alveolar wall and a small amount of lymphocyte aggregation visible in the peribronchial space. On the 60th day, only half of the mice showed slight alveolar collapse and incomplete expansion, accompanied by focal inflammation dominated by lymphocytes. Others are close to normal.

　　After nasal administration, the control group showed mild alveolar wall congestion and edema on the third day, local thickening, and a small amount of neutrophil infiltration around capillaries. By the 21st to 60th day, the aforementioned changes had basically disappeared, and lymphocyte infiltration was occasionally observed near the bronchi.