【Animal Modeling】-Making Transplanted Lymphoma

      [Modeling mechanism] Using established lymphoma cell lines or patient lymphoma tissue transplanted into immunodeficient animals, transplanted lymphoma models can be established and tumor characteristics can be characterized. At present, transplanted lymphoma models mainly adopt two transplantation methods at home and abroad: cell transplantation and tissue block transplantation.

  [Modeling method]

  1, 1 x 1,000,000 cells/mouse Transplanted legitimate human lymphocytes (Raji) intraperitoneally into female BALB/c-nu/nu mice for 5-6 weeks. Ascites usually occurs within 22 days. The more cells inoculated, the shorter the time for ascites to appear. This model can be passed continuously. Under sterile conditions, transplanted tumors can be harvested from nude mice to produce cell suspensions or ascites tumor cells. After centrifugation, ascites can be formed from the primary cells seeded as described above.

  2. Using the method of tissue orthotopic transplantation, human primary colorectal malignant lymphoma and liver metastases are collected during the operation, fresh tumor tissue pieces are collected during the operation, the receiving animal is anesthetized, and a midline abdominal incision is performed. Use serosal membrane to identify the colorectum. Make a 3 mm incision in the mucosal layer facing the intestinal wall, and use 10.0 non-invasive sutures to cut out a 1 cubic millimeter tumor mass from the incision and implant it into the large intestine mucosal layer of nude mice, and fix it on the intestinal mucosa layer , And close the abdominal stitches. skin. After that, we performed in vivo in situ organ screening, transplanted a small 1 mm3 tumor from the liver metastases derived from the same tumor to another mucosal layer of the colon of nude mice, and transplanted tumorigenic liver metastases into nude mice The mucosal layer of the colon. Repeated 4 consecutive screenings in nude mice. Collect liver metastases from nude mice for colon transplantation and maintain them after surgery. The observation period is 60-90 days. When the tumor-bearing nude mouse died, a tumor-bearing nude mouse was killed by cervical dislocation, and the transplanted tumor was taken out by whole body dissection. Part of the tumor tissue was serially passaged between mice through the initial transplantation, and the range of each passage was 5-10. The other part of the tumor tissue is frozen and stored in liquid nitrogen for future use in testing related indicators. Observe the nude mice carrying tumors or make them die or die naturally, and observe their growth, invasion and metastasis.

  [Model Features] 1. The cell transplantation model has ascites formation, usually about 10 ml, and a large number of tumor cells can be seen under the microscope. In the abdominal cavity, tumor masses are mainly distributed in the mesentery, near the intestinal wall and lymph nodes, and the thickening of mesenteric adhesion is very obvious. Tumor cells are uniform in size, with deep nuclear staining, more nuclear divisions, tight interstitial arrangement, a few tumor nodules, obvious necrosis, obvious spleen infiltration, follicular hyperplasia, obvious germinal centers, many tumors without megakaryocytes, liver, kidney and lung Cell infiltration. Chromosome examination showed that in all ploidy, the type of centromeric band was consistent with the human chromosomal characteristics of human chromosomes. Cell inoculation is usually used by intraperitoneal or subcutaneous injection. Generally speaking, the subcutaneous model after inoculation is convenient for research and observation due to loose skin, faster growth of tumor nodules and corresponding increase in host life span. Injection molded cell lines can establish 8-cell lymphoma peritoneal models that can be serially passaged. The tumor formation rate was 100%.

  2. Orthotopic tissue transplantation is a highly metastatic model of human colonic malignant lymphoma. It is compatible with human origin in terms of histopathology, immunohistochemical phenotype, ultrastructure, DNA ploidy level and chromosome karyotype. Don't just do. Colorectal malignant lymphoma cells meet a 100% growth rate for tumor transplantation, liquid nitrogen cryopreservation and survival.

  [Model Evaluation and Application]

   1. The transplantable tumor model is the most commonly used animal model for screening new anti-tumor drugs. Its advantages include easy handling and use of interfering factors, stable tumor formation in animals, high tumorigenicity, small individual differences, slight differences in tumor formation time, and long-term preservation of the same species for testing. Or continuous transplantation with animal strains. However, this type of tumor has a high growth rate, a high growth rate, a short doubling time, and is very different from human tumors.

  2. The spontaneous metastasis model is a difficult problem in the research field of human cancer metastasis models. The metastasis model established by the above-mentioned tissue in situ implantation method has stable biological characteristics and provides basic experimental materials for studying the spontaneous metastasis of gastrointestinal malignant lymphoma. This method plays an irreplaceable role in the detailed study of biological characteristics, tissue development, etiology and pathology, mechanisms of invasion and metastasis, and experimental treatment of rectal and colonic malignant lymphomas.