动物造模,药效评价,同种异体移植骨肿瘤 z-bio 2024-08-02 524

　　Allogeneic transplantation refers to the transplantation of the same or homologous animal species, with a high degree of commonality between the donor and recipient, making it easy to stay in the body, grow and reproduce, and reproduce the tumor process. Usually, Sprague Dawley rats less than 6 weeks old (at this stage, the immune function of rats is not yet fully developed) are selected for allogeneic bone in situ transplantation. The rat osteosarcoma cell line UMR106 is used for allogeneic bone in situ transplantation. This cell line was obtained from Sprague Dawley rats induced by radioactive phosphorus in the 1970s and has recently been used to construct an in situ transplantation model of osteosarcoma. It has a high tumor formation rate and strong lung metastasis ability, making it an ideal cell line for lung metastasis research. Tumor cells can achieve a high success rate by escaping and growing in the absence of effective immune monitoring conditions. At present, there are many cell lines or cell strains available for selection and use, many of which are widely distributed worldwide, and the biological characteristics of these cells are relatively clear. Generally, there is clear background information, so that a group of animals can be inoculated with the same amount of tumor cells at the same time, with consistent growth rate, small individual differences, high survival rate, and easy control and observation. These are favorable factors for comparing and exchanging scientific research results.

　　[Method of Modeling]

　　1. Cultivate rat osteosarcoma cell line UMR-106 in vitro and obtain logarithmic growth phase cells for future use. Select 30-40 day old Wistar rats, half male and half female, and inject ketamine hydrochloride injection intramuscularly for anesthesia (0.1g/kg). Disinfect the lower limbs with iodine. Make an incision on the inner side of the metaphysis of the upper tibia or the outer side of the lower femur, separate the subcutaneous tissue and expose the bone surface. Use a 1mm diameter Kirschner wire to gently drill into the bone marrow cavity with a clear sense of disappointment. Then use a No.12 transfusion needle to diagonally drill into the bone marrow cavity along this empty space, excavate the bone marrow and trabecular bone, form an inclined channel, and dilute the spare osteosarcoma cells into 5 × 1000000/ml with serum-free RPMI 1640 culture medium. Inject 0.2ml into each bone marrow cavity, seal with bone wax, suture the muscle membrane and skin in sequence, disinfect the incision, and wrap it. Feeding observation, successful modeling can be achieved in 4 weeks.

　　2. VX2 cell line was selected as the research object in rabbits. Cell suspension was first injected into the hind limb muscles of rabbits to prepare tumor bearing rabbits. After 3 weeks, when the tumor grew to a mass with a diameter of about 5cm, fresh fish like tumor tissue was cut into pieces, placed in a 200-400 mesh cell sieve, squeezed and filtered, and washed with Hanks' solution. Collect the cell suspension, centrifuge at 1500r/min for 3 minutes, and resuspend the resulting pellet in Hanks' solution to prepare a 1 × 1000000/ml tumor cell suspension. Anesthetize the experimental animals under sterile conditions. A longitudinal incision of approximately 1cm was made under the patella of the right knee joint, touching the tibial plateau. An 18G bone puncture needle was inserted through the proximal articular surface of the tibia, parallel to the tibial shaft. When the puncture needle was rotated, it entered the bone marrow cavity and was inserted into the bone marrow cavity at a depth of 2.0-2.5cm. The needle tip was located in the upper part of the tibial bone marrow cavity, and 0.3ml of tumor cell suspension was injected. The needle was removed and the skin was sutured.

　　【 Model features 】 Rats were inoculated with tumor cells and implanted into the bone. Three weeks later, the epiphysis showed swelling, and abundant tortuous small blood vessels were visible subcutaneously in the tumor area; On the cut surface, there is visible destruction and rupture of the endoplasmic reticulum, and the tumor has invaded soft tissue. The tumor tissue inside and outside the cavity appears fish like; Four weeks after transplantation, the epiphyseal end undergoes spherical swelling, with a mass diameter of up to 2-3cm. The mass is medium to slightly hard in texture, with more obvious cortical bone destruction. There are also a small number of metastases at the hilum and edge of the lung, varying in size; Six weeks after transplantation, the tumor appeared as a giant spherical shape with slightly hard texture; The cortical bone of the epiphyseal section has disappeared, only the residual end of the shaft can be seen; Numerous metastatic tumors of varying sizes were observed in both lungs, with some tumor foci fused and appearing grayish white; Seven weeks after transplantation, the diameter of the tumor in the right lower limb can reach 3-5cm, with extensive metastases in both lungs, tumor fusion, and basic disappearance of normal lung tissue structure. The natural survival period of model mice is about 7 weeks.

　　The success rate of the rat model is slightly lower than that of the nude mouse tumor bearing model, but if the tumor tissue that has grown and metastasized after inoculation is homogenized and then inoculated, the success rate will increase. Although the repulsion between animals of the same species is relatively weak, individuals in different environments,

　　Due to significant physiological differences, reducing immunity or changing vaccination methods can also increase tumor formation. This model has a short experimental period, low animal costs, and is easy to raise and manage, so it is widely used. The rabbit model implants tumors into the bone marrow cavity of the upper and middle segments of the tibia through proximal tibial articular surface puncture, which minimizes mechanical damage to the periosteum. The puncture hole is relatively far from the tumor implantation site, making it difficult for the tumor to grow outward through the hole.