| Cervical cancer is the most common in developing countries. A lot of evidences exist to show that both the incidence and mortality rate can be reduced by the use of cervical screening programs. However, cervical cancer remains still the second leading cause of cancer death among women in developing countries. The major causative agent of this disease is considered to be human papillomavirus (HPV) infection. Over the past 15 years, epidemiological data have identified the fact that there is a consistently strong relationship between HPV infection and cervical neoplasia, and HPV DNA has been detected in more than 99.7% of cervical cancer and its precursors. The use of HPV typing shows that HPV 16 is a predominant etiological agent and presents in approximately 50% of all the disease . Therefore, HPV 16 has become a target for the development of HPV vaccine . In addition to infectious factor, immunosuppression is another risk factor for the development of cervical cancer. In studies of women with immunosuppression such as renal transplants and HIV-infected,significantly higher incidence of cervical cancer was found.Routine laboratory methods for culturing HPV in vitro are not available .There is longproceeding from HPV infection to suffering from cervical cancer. So a suitable animal model is very important. The earliest animal model for cervical cancer was general animal, but its tumorigenecity was very low. Nude-mouse transplantation system is commonly used for growing xenografted human tumor today, with a higher tumorigenecity rate . However, it appears to be not an ideal animal model for simulating accurately the features of human spontaneous tumor because there still exists humoral immunity in nude mice. Severe combined immunodeficient (SCID) mice make the research of animal transplantation system for human tumor forward. The main character of SCID mice is lack of both T and B lymphocytes . Therefore, SCID mice become a better animal model for transplantation of human tumors. It has been reported that various kinds of human tumors are successfully inoculated into SCID mice . Moreover, SCID mice are also used for reconstruction of human immune system because of their deficiency of both humoral and cellular immunity. Mosier et al firstly established a stable humanized model in 1988. Thereafter, humanized SCID mice are considered to be the most available animal model for investigating relationship between tumor and host immunity.Although the models of transplanting different tumors into humanized SCID mice were established, no one for cervical cancer was reported. In this study, we transplanted HPV-16 positive SiHa cells subcutaneously into SCID mice, and successfully established an ideal animal model of human cervical cancer, which simulated perfectly the biological features of spontaneous human cervical cancer and presented anti-tumor immune response after human immune system was reconstructed via inoculating intraperitoneally human peripheral blood cells into SCID mice.Material and MethodsThirty-two nonleakage female C.B-17 scid/scid mice were randomly divided into four groups. Group PBS-SCID (5 mice): subcutaneously injected with PBS as a control group. Group Hu-PBL-SCID (5 mice): intraperineally injected with hu-PBL as a humanized group. GroupSiHa-SCID (11 mice): subcutaneously injected with HPV16- positive Siha as a transplantation group. Group Hu-PBL-SiHa-SCID(11 mice): intraperineally injected with hu-PBL and subcutaneously injected with Siha after 24 hours of hu-PBL transplantation as a humanized transplantation group. Group SiHa-SCID and Group Hu-PBL-SiHa-SCID were further randomly divided into two groups: In group one (6 mice), the mice were executed on the 90th days for detecting immunological status, and in group two (5 mice), the mice were raised until they spontaneously died.Observation of biological features:including tumorigenecity, general characteristic, tumor growth and metastasis, survival time, gross and histological features of transplanted tumor, morphology of pr...
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