Induction of T-cell immunity against Epstein-Barr virus-associated tumors by means of adenovirally transduced dendritic cells

Background Dendritic cells (DCs) are the most powerful antigen-presenting cells to induce specific T-cell immunity, which plays an important role in the body‘s anti-tumor responses. In this study, we assessed the feasibility and efficacy of inducing T-cell immunity against Epstein-Barr virus (EBV)- associated tumors in vivo using dendritic cells transfected with EBV latent membrane 2A (LMP2A) recombinant adenovirus.Methods Cytokine-activated bone marrow-derived DCs transfected with EBV LMP2A recombin antadenovirus were infused into BALB/c mice. Splenic cytotoxic T-cell responses were evaluated by cytotoxicity and interferon-γ production assays, in vivo immune protection was then assessed in the mice tumor models implanted with tumor cells expressing EBV LMP2A. Results DCs transfected with EBV LMP2A recombinant adenovirus could strongly induce EBV LMP2A-specific cytotoxic T-cell responses and upregulate interferon-y production in vivo. Vaccination using these DCs led to prolongation of overall survival rates in the mice tumor models and retarded tumor growth.Conclusions The results suggest that DCs transfected with EBV LMP2A recombinant adenovirus can serve as a feasible and effective tool for eliciting LMP2A-specific cytotoxic T-cell responses against EBV LMP2A in vivo in the treatment of EBV-associated tumors.     

Altered CD28 and CD95 mRNA expression in peripheral blood mononuclear cells from elderly patients with primary non-small cell lung cancer

Background The expression of the co-stimulatory molecule CD28 and death receptor CD95 on T cells, which change with age, are considered as important immunological parameters of immunosenescence. It is well established that CD28 and CD95 are associated with tumorgenesis and tumor progression, but the relationship between the age-related changes of these two immunological markers and cancer in the elderly is largely unknown. Methods The levels of CD28 and CD95 mRNA in peripheral blood mononuclear cells （PBMCs） from sixty-three elderly patients （aged 〉60 years） with primary non-small cell lung cancer （NSCLC） were analyzed by real-time fluorescence-based quantitative polymerase chain reaction （FQ-PCR）. In addition, twenty young patients （aged 〈60 years） with NSCLC, thirty elderly healthy donors and thirty young healthy donors were enrolled as controls. Results CD28 mRNA levels were significantly lower and CD95 mRNA levels were significantly higher in elderly patients with NSCLC than in the other groups. Similar results were found in elderly healthy donors comparing with young healthy donors. By Logistic regression analysis an increased risk of NSCLC was markedly associated with aging, down-regulation of CD28 mRNA and up-regulation of CD95 mRNA, and CD28 mRNA had an obvious negative correlation with the CD95 mRNA. In addition, the mRNA levels of CD28 and CD95 in the peripheral blood of the elderly patients was closely associated with the tumor node metastasis （TNM） stages, grade of cell differentiation and lymph node metastasis status, but not related to pathological types. Conclusions The results suggest a close relationship between T cell senescence and NSCLC tumour progress in the elderly, and that up-regulation of CD28 mRNA or down-regulation of CD95 mRNA in peripheral blood T cells may play an important role in inhibiting oncogenesis and development of primary NSCLC in the elderly.     

INVESTIGATION OF REGULATORY T CELLS IN PATIENTS WITH NON-SMALL CELL LUNG CANCER

Objective To evaluate the prevalence of CD4 ^＋ CD25^high regulatory T cells （ Treg cells） in the peripheral blood mononuclear cells （PBMC） and tumor-infiltrating lymphocytes （TIL） of patients with non-small cell lung cancer （NSCLC） and to investigate immunosuppression to the progression of cancer. Methods Peripheral blood and tumor tissues were collected from 20 patients with NSCLC at the time of surgery. None of the patients received surgery, radiotherapy, chemotherapy, or other medical interventions before this study. Cancer stages of the patients were Ⅰ-Ⅲ A. Venous blood samples were obtained from 20 health donors. PBMC were isolated from blood samples by differential centrifugation over Ficoll-Hypaque. TILs were isolated from tumors by differential centrifugation over Ficoll-Hypaque and Percoll. Percentage of CD4^＋ CD25^highTr/CD4＋T in PBMC and TIL was assessed by the flow cytometry. Results The percentage of CD4^ ＋ CD25high Tr/ CD4 ^＋T in PBMC [ （4. 87 ± 1.22 ） % ] of NSCLC patients was significantly higher than that in healthy donors [ （ 2.36 ± 0. 72 ） % ] （ P 〈 0.01 ）. The percentage of CD4^＋ CD25^highTr/ CD4^＋ T in PBMC [ （5.40 ± 1.20） % ] of NSCLC patients in stage Ⅱ-Ⅲ A was significantly higher than that in stage Ⅰ [ （3. 87 ± 0. 22 ） % ] （ P 〈 0. 01 ）. The percentage of CD4 ＋ CD25hiShTr/ CD4 ＋ T in TIL[ （ 8. 66 ±0. 76） % ] of NSCLC patients in stage Ⅱ-Ⅲ A was significantly higher than that in stage Ⅰ [ （ 7. 04 ± 0. 80） % ] （ P 〈 0. 01 ）. Conclusion The prevalence of CD4 ^＋ CD25^highTreg cells in PBMC and TIL of NSCLC patients was significantly higher than that in healthy donors. These Treg cells may be preventing appropriate antitumor immune responses. The population of CD4^ ＋ CD25^highTreg cells in PBMC and TILs of NSCLC patients with Ⅱ-Ⅲ A stage was significantly higher than that of NSCLC patients with Ⅰ stage. These Treg cells may facilitate development of tumors.     

Effector cells derived from naive T cells used in tumor immunotherapy of mice bearing B16 melanoma

Background Adoptive cell transfer （ACT） immunotherapy has been used clinically for years to treat malignancies.Improving the killing efficiency of effector cells,such as tumor-specific cytotoxic T lymphocytes （CTLs）,is an important component for enhancing the clinical response of cancer immunotherapy.Hence,we explored a novel method for preparing cancer-specific CTLs using naive T lymphocytes.Methods C57BL/6 mice bearing B16 melanoma tumors were pretreated with cyclophosphamide （CTX） by peritoneal injection.The immunosuppressive influence of CTX on tumor regression and the tumor microenvironment was assessed.Naive T cells and T cell pools were isolated via negative selection using immunomagnetic beads.The proliferative potential and cytokine production of different T cell subpopulations were evaluated in vitro.Tumor-specific CTLs derived from naive T cells （naive CD4＋ T cells：naive CD8＋ T cells=2：1） and pooled T cells were generated in vitro,respectively.B16 melanoma-bearing C57BL/6 mice were pretreated with CTX,followed by ACT immunotherapy using dendritic cell-induced CTLs.The homing abilities of the effector cells and interleukin-2 （IL-2）,interferon-y,granzyme B,and perforin mRNA levels in tumor tissues were evaluated,and the change in tumor volume was measured.Results Mice receiving CTX peritoneal pretreatment injections did not display tumor regression compared with control mice.However,a significant downregulation of splenic Tregs and tumor growth factor-β1 （TGF-β1） and interleukin-10 （IL-10） serum levels was observed （P ＜0.05）.Naive T cells showed a stronger proliferative capacity and elevated cytokine production than did pooled T cells （P ＜0.05）.In addition,effector cells generated from naive T cells displayed more potent antitumor activity in vivo than those derived from pooled T cells （P ＜0.05）.Conclusion Effector cells derived from the naive T cells possess a stronger proliferative potential,homing capacity,and enhanced cytokine production,which leads to a superior antitumor response.     

Isolation and characterization of cancer stem-like cells from MHCC97H Cell Lines

Objective:To identify and isolate CD133 positive cancer stem-like cells (CD133+ cells) from the highly invasive human hepatocellular carcinoma cell line(MHCC97H), and examine their potential for clonogenicity and tumorigenicity. Methods: CD133+ and CD133- cells were isolated from MHCC97H cell line by magnetic bead cell sorting(MACS), and the potentials of CD133+ cells for colony formation and tumorigenicity were evaluated by soft agar cloning and tumor formation following nude mice inoculation. Results:CD133+ cells represent a minority(0.5-2.0%) of the tumor cell population with a greater colony-forming efficiency and greater tumor production ability. The colony-forming efficiency of CD133+ cells in soft agar was significantly higher than CD133- cells(36.8±1.4 vs 12.9±0.8, P＜0.05).After 6 weeks, 3/5 mice inoculated with 1 × 103 CD133+ cells, 4/5 with 1 × 104 CD133+ cells and 5/5 with 1 × 105 CD133+ cells developed detectable tumors at the injection site, while only one tumor was found in mice treated with same numbers of CD133- cells. Conclusion: CD133 may be a hallmark of liver cancer stem cells (CSC) in human hepatocellular carcinoma(HCC), because the CD133+ cells identified and isolated with anti-CD133 labeled magnetic beads from MHCC97H cell line exhibit high potentials for clonogenicity and tumorigenicity. These CD133+ cells might contribute to hepatocarcinogenesis, as well as the growth and recurrence of human HCC, and therefore may be a useful target for anti-cancer therapy.     

Potent in Vivo Anti-tumor Activity of Isolated CD62 Llow Lymph Node Cells Sensitized in Vivo With tumor Lysate-pulsed DC-based Vaccines

Background DC are potent APC that can activate both CD4 and CD8 T cells in vitro and in vivo. Although the efficacy of DC-hased cancer vaccines is currently being evaluated in clinical trials, the systemic immune suppression in cancer patients negatively impacts the clinical benefit of this therapeutic approach. Therefore, in this study we tested the feasibility and anti-tumor effect of adoptive immunotherapy using in vitro-activated CD62Llow lymph node cells that were isolated from DC-vaccinated draining lymph nodes （VDLN）. Methods DC were prepared from BM cells and loaded with tumor lysate for inoculating into naive mice. Subsequently, the VDLN were removed and CD62 Llow cells in the VDLN population isolated, expanded in vitro by 5-day culture with IL-2 and immobilized anti-CD3 stimulation, then injected into mice with established pulmonary tumors. Eighteen days after treatment, mice were killed in order to enumeratepulmonary tumor nodes. Results DC phagocytosed the tumor lysate efficiently and induced detectable T-cell responses and significant cell expansion in the draining lymph nodes. After induction of maturation by LPS treatment, DC expressed higher levels of CD40, CD86 and MHC class Ⅱ molecules. When CD62Llow VDLN cells that had been isolated and expanded in vitro were transferred into tumor-bearing mice, as few as 3 ＊ 106 cells were able to cure metastatic pulmonary tumors in vivo. Conclusion DC-hased VDLN T cells are an important source of anti-tumor effector for adoptive immunotherapy. This study provides a novel and an effective protocol using T-cell adoptive immunotherapy for application in cancer patients; therefore, clinical trials based on this protocol may be warranted.     

Analysis of Epstein-Barr viral DNA load,EBV-LMP2 specific cytotoxic T-lymphocytes and levels of CD4^＋CD25^＋ T ceils in patients with nasopharyngeal carcinomas positive for IgA antibody to EBV viral capsid antigen

Background Epstein-Barr virus （EBV） is a herpesvirus commonly associated with several malignant diseases including nasopharyngeal carcinoma （NPC）, which is a common cancer in Southeastern Asia. Previous studies showed that plasma levels of EBV-DNA might be a sensitive and reliable biomarker for the diagnosis, staging and evaluating of therapy for NPC. There are a few analyses of the levels of EBV-latent membrane protein 2 （LMP2）-specific cytotoxic T-lymphocytes （CTLs） in patients with NPC. This study was conducted to investigate the levels of EBV-LMP2-specific CTLs, EBV-DNA load and the level of CD4^＋CD25^＋T cells in such patients.
Methods From February 2006 to April 2006, 62 patients with NPC, 40 healthy virus carriers positive for EBV viral capsid antigen （EBV-IgA-VCA） and 40 controls were enrolled in the study. We used a highly sensitive ELISPOT assay, real-time polymerase chain reaction （PCR） and flow cytometry to measure the EBV-LMP2-specific CTL response, the EBV DNA load and the level of CD4^＋CD25^＋T cells, respectively.
Results The EBV-LMP2-specific CTL responses of the samples from the control, healthy virus carriers and patients with NPC were significantly different from the LMP2 epitopes, with the control and healthy virus carrier samples displaying a stronger response in three cases. There were significant differences in EBV DNA load in serum between NPC and the healthy groups; patients with NPC at stages Ⅲ or Ⅳ had significantly higher viral loads compared with those at stages Ⅰ or Ⅱ. A significantly higher percentage of CD4^＋CD25^＋ T lymphocytes were detected in the patients, compared with healthy virus carriers and healthy controls. Moreover, patients with advanced stages of NPC （Ⅲ and Ⅳ） had significantly higher percentages than the patients with early stages （Ⅰ and Ⅱ）. Conclusions Patients with NPC are frequently unable to establish or maintain sufficient immunosurveillance to control proliferating B cells harboring EBV and to destroy the tumor cells that express immunodominant LMP2 proteins.
Controlling the activity of CD4^＋CD25^＋T cells and elevating CD8^＋ cells specific for LMP2 epitopes could be an effective immunotherapy for patients with NPC.     

Changes of regulatory T cells and FoxP3 gene expression in the aging process and its relationship with lung tumors in humans and mice

Background  Immunosuppressive regulatory T cells (Tregs) participate in tumor immune evasion and the number and suppressive function of Tregs change with the aging process, but it is not clear whether such change leads to a higher incidence of tumors in the elderly. To this end, we designed experiments to explore the changes of Tregs and the functional gene Forkhead box P3 (FoxP3) in the aging process and its relationship with lung tumors in humans and mice.

Methods  The percentage of CD4⁺CD25⁺CD127^low Tregs and expression of FoxP3 mRNA were analyzed using flow cytometry (FCM) and real-time fluorescence-based quantitative polymerase chain reaction (FQ-PCR). Markers were analyzed in the peripheral blood (PB) of 65 elderly patients (age ≥65 years) with primary non-small cell lung cancer (NSCLC), 20 younger patients (aged <55 years) with NSCLC, 30 elderly healthy individuals and 30 young healthy individuals. Furthermore, we set up the Lewis lung cancer model with C57BL/6 female mice. Thirty-six mice were divided into a young healthy group, a middle-aged healthy group, an elderly healthy group, a young tumor group, a middle-aged tumor group, and an elderly tumor group. The percentage of CD4⁺CD25⁺FoxP3⁺ Tregs and the expression level of FoxP3 mRNA in splenocytes were determined in the six groups.

Results  The percentage of peripheral CD4⁺CD25⁺CD127^low Tregs and the expression of FoxP3 mRNA were significantly increased in elderly patients with NSCLC comparing with the other groups and in elderly healthy individuals compared with young healthy individuals. Further analysis showed that the percentage of CD4⁺CD25⁺CD127^low Tregs and the expression of FoxP3 mRNA were closely associated with tumor node metastasis (TNM) staging in elderly patients with NSCLC. In the mouse model, the percentage of CD4⁺CD25⁺FoxP3⁺ Tregs and the expression of FoxP3 mRNA in splenocytes of the tumor groups were significantly higher than in the healthy groups, with the highest expression in the elderly tumor group. In the healthy groups, the elderly healthy mice had the highest percentage of Tregs and expression of FoxP3 mRNA. The elderly mice had larger and heavier tumors than did the young and middle aged mice.

Conclusions  The up-regulation of Tregs and the FoxP3 gene with aging may play an essential role in oncogenesis and development of lung tumors in an elderly population.

     

THE INFLUENCE OF HUMAN SINGLE CHAIN INTELEUKIN-12 GENE TRANSDUCTION ON THE BIOLOGICAL BEHAVIOR OF HEPATOMA 7721 CELLS

Objective. To investigate the anti-tumor effects of human single chain interleukin-12 (hscIL-12). Method. pcDNA/hscIL-12 recombinant was transfected into human hepatic carcinoma cells (7721 cells) by lipofectin method. The 7721/hscIL-12 cells which secrete hscIL-12 stably, were obtained via G418 selection, and in vitro the influence of hscIL-12 gene transduction on the growth of tumor cells was evaluated by cellcycle analysis. In vivo, genetically engineered 7721 cells (7721/hscIL-12, 7721/pcDNA) and parental cells were implanted into BALB/c nude mice, respectively. 7721/pcDNA and 7721/hscIL-12 groups were divided into two sub-groups on day 8: one was administered with hPBL twice, 6 days at interval; the other was given equalvolume of PBS. Mice were sacrificed on day 26, and spleens and tumors were taken out for histologic assay. Results. hscIL-12 produced stably by 7721/hscIL-12 cells had bioactivity, and it was proved by Western blot, immunocytochemistry, and in situ hybridization. In vitro, compared with 7721 and 7721/pcDNA, the7721/hscIL-12 grew much more slowly. FACS assay showed apparent G1 arrest of 7721/hscIL-12 cells. In ani-mal experiment, on day 8 after inoculation, the tumors of 7721 and 7721/pcDNA group were up to 5 -7mm,while those of 7721/hscIL-12 group were 2 -4mm. When treated with hPBL, the tumor of 7721/hscIL-12 groupdisappeared completely. Histologically, the tumors from 7721/hscIL-12 without hPBL treatment had numerouslymphocyte infiltration, the tumor cells displayed depression looking, atrophy, focal necrosis and apoptosis, whereas the tumors of 7721 and 772l/pcDNA groups grew thrivingly.Conclusion. hsclL-12 transduced 7721 cells could induced significant antitumor immune response which resulted in tumor regression totally when the hPBL was inoculated, and also hscIL-12 has certain effects on mice immune system. These findings suggest that hscIL-12 and hscIL-12 gene therapy might have promising prospects in clinical application.     

免疫重建SCID小鼠B淋巴母细胞瘤模型的建立

目的在免疫重建的严重联合免疫缺陷(severecombinedimmunodeficient,SCID)小鼠体内建立人的B淋巴母细胞瘤模型。方法将SCID小鼠随机分为4组,每组7只,分别为:(1)实验组:在每只SCID小鼠的腹腔内接种人外周血单个核细胞(peripheral-bloodmononuclearcells,PBMC)1周后,腹腔接种EB病毒(Epstein-Barrvirus,EBV)悬液;(2)不经任何处理的SCID小鼠对照组;(3)腹腔接种人PBMC的SCID小鼠对照组;(4)腹腔接种EBV悬液的SCID小鼠对照组。每日观察小鼠的健康情况,于免疫重建的第5周解剖各组小鼠,观察腹腔各脏器的肿瘤形成情况,并用HE染色、组织化学以及PCR方法鉴定所长肿瘤的特性。结果4周后,在接种EBV的免疫重建SCID小鼠的腹腔中可形成(35±12.5)mm3大小的肿瘤,多位于肝脏,而对照组均未见有肿瘤生长;HE染色表明,所长的肿瘤均为高分化的B淋巴母细胞瘤;组织化学实验表明,肿瘤细胞均可表达CD19、CD20、CD45RA分子和EB病毒编码的蛋白;PCR检测显示,肿瘤组织的DNA在269bp处出现特异的EBV扩增条带。结论成功建立了免疫重建SCID小鼠的人B淋巴母细胞瘤模型,为研究人类肿瘤免疫提供了一个理想的动物模型。     

hu-PBL-SCID小鼠体内人淋巴细胞状况及其对人肺癌移植瘤转移的影响

将人外周血淋巴细胞经腹腔移植于T、B细胞严重联合免疫缺陷的SCID小鼠后,成功地建立了hu - PBL- SCID小鼠模型。在移植后4 周,其小鼠血清中存在人免疫球蛋白,其脾淋巴细胞中,所检测的8 种免疫表型人淋巴细胞亚群均存在,表明人淋巴细胞在SCID小鼠体内出现了增殖或重建。但hu- PBL- SCID小鼠及未免疫重建的SCID小鼠体内人肺巨细胞癌PLA- 801DL的生长及转移情况未见明显差异,提示hu- PBL- SCID小鼠体内的人淋巴细胞不具有明显的抗肿瘤活性。     

hu-PBL-SCID人鼠嵌合体细胞免疫的建立及其免疫功能检测

目的：探讨腹腔注射人外周血CD4＋T淋巴细胞后,SCID小鼠能否重建人的细胞免疫系统,并观察重建后免疫系统的特点与功能。方法：从人外周血分离得到CD4+T淋巴细胞,腹腔注射至SCID小鼠体内,并予以rIL-2刺激。注射细胞6周后,分批处死动物,用PCR和免疫组织化学法分别观察SCID小鼠是否表达人的淋巴细胞DNA 及其T,B淋巴细胞表型;移植异种移植物后测定血浆中人IL-2,TNF-α,INF-γ含量。结果：腹腔注射人外周血CD4+T淋巴细胞后, SCID小鼠脾脏体积增大;外周血PCR扩增可见人淋巴细胞HLA-II恒定区DNA片段;肝、脾免疫组织化学染色可见到大量的人CD4+T淋巴细胞,而没有CD8＋,CD19＋T淋巴细胞;移植后重建SCID小鼠血清中可检测到人IL-2,INF-γ。结论：腹腔注射人外周血CD4+T淋巴细胞可选择性重建SCID小鼠人细胞免疫系统;方法简单、迅速、供体来源广。     

人免疫重建荷人人乳头瘤病毒16阳性宫颈癌-严重联合免疫缺陷鼠模型的建立及其免疫学特性研究

目的　建立人免疫重建荷人人乳头瘤病毒 (HPV) 16阳性宫颈癌 严重联合免疫缺陷(SCID)小鼠模型并研究其免疫学特性。方法　对SCID鼠腹腔注射人外周血淋巴细胞 (hu PBL)后2 4h ,皮下接种HPV16阳性的人宫颈癌细胞株SiHa细胞建立人免疫重建荷人HPV16阳性宫颈癌SCID鼠模型 ,观察荷瘤鼠的一般生物学特性、异种移植物抗宿主病 (XGVHD)情况 ,检测血清中人IgG含量、外周血和脾中人CD3 、CD4 和CD8 T细胞、脾重、肿瘤浸润淋巴细胞 (TIL)以及脾细胞毒杀伤功能。结果　免疫重建的小鼠成瘤率为 10 0 %。未发现异种移植物抗宿主反应。荷瘤第 5天 ,血浆中人IgG水平人化组 (0 98μg/ml± 0 2 0 μg/ml)、人化荷瘤组 (1 39μg/ml± 0 2 5 μg/ml)均显著高于空白组 (0 2 0 μg/ml± 0 11μg/ml) (t=7 6 5 5、9 937,均P =0 0 0 0 ) ,人化荷瘤组显著高于人化组 (t=3 2 0 0 ,P =0 0 0 6 ) ,荷瘤组与空白组比较差异无显著意义 (t=0 0 90 ,P =0 930 )。 30d内免疫重建组血浆中人IgG水平随重建时间延长而升高 ,与未人化组比显著升高 (P <0 0 5 )。外周血和脾中人CD3 ,CD4 和CD8 T细胞均显著升高 (P <0 0 5 ) ,脾重显著增加 (P <0 0 5 )。组织学观察到移植瘤局部TIL浸润并经免疫组织化学检测到人CD4 T细胞     

人免疫重建NOD/SCID小鼠模型的建立

目的探讨NOD/SCID（nonobese diabetic/severe combined immunodeficien）t小鼠人免疫重建模型的建立方法和免疫特性.方法 16只NOD/SCID小鼠随机分成实验组和对照组,每组8只.Ficoll密度梯度离心法分离人外周血单个核细胞（peripheral blood mononuclear cell,PBMC）,通过腹腔注射移植给实验组小鼠,空白对照组小鼠每只腹腔注射无菌PBS,第4、8和12周时,流式细胞术检测小鼠外周血中人的CD3＋T、CD19＋B淋巴细胞,ELISA法测定小鼠血清中人IgG含量,免疫组织化学染色检测小鼠脾脏和肝脏中人CD3＋T、CD19＋B淋巴细胞浸润情况.结果移植PBMC 4周后,实验组NOD/SCID小鼠外周血中人CD3＋T、CD19＋B的细胞分别为85.6%、76.7%,并且在小鼠脾脏组织中也可以检测到人CD3 T、CD19 B淋巴细胞.移植4、8及12周后小鼠血清中人IgG含量分别达到（863±12.5）μg/mL、（1217±16.7）μg/mL、（958±13.1）μg/mL.结论用人外周血PBMC经腹腔注射可以成功建立人免疫重建NOD/SCID小鼠模型,方法简便可靠.     

SCID鼠人脾脏淋巴细胞植入及其免疫功能检测的实验研究

目的将人脾脏淋巴细胞植入SCID鼠体内,检测植入细胞的免疫功能。方法人脾脏淋巴细胞经腹腔注入SCID鼠后,检测鼠外周血淋巴细胞分类及人IgG含量。植入人淋巴细胞的SCID鼠与异体人外周血淋巴细胞混合培养后测其增殖程度。移植异体人皮肤后观察免疫排斥的迹象。结果淋巴细胞腹腔注入SCID鼠后能够存活并分泌一定量的人IgG。混合培养后植入SCID鼠淋巴细胞明显增殖。移植的异体人皮肤被排斥。结论SCID鼠体内植入的人淋巴细胞能够存活,仍具有一定的免疫功能。     

EB病毒核抗原-1特异性核酶对成淋巴细胞系肿瘤形成能力的影响

目的 探讨腺病毒载体介导的ＥＢ病毒核抗原－１（ＥＢＮＡ－１）特异性核酶对成淋巴细胞系（ＬＣＬｓ）在严重的联合免疫缺陷（ＳＣＩＤ）小鼠体内致瘤性的影响,方法 用分子克隆技术构建ＥＢＮＡ－１核酶（ＲＺ１）及其无活性诱变体（ＲＺ１ ｍｕｔ）的重组腺病毒表达载体（Ａｄ．ＲＺ１和Ａｄ．ＲＺ１ｍｕｔ）。通过同源重组方式在２９３细胞生成腺病毒,并通过噬斑形成进行分离建立ＬＣＬ。将感染重组腺病毒的ＬＣＬ细胞注射于     

人肝癌细胞系9724在不同免疫缺陷小鼠中的增殖特点

目的 探讨人类肝癌细胞9724在不同免疫缺陷小鼠的生长及模型特点。方法 体外培养人类肝癌细胞9724；按种到不同免疫力小鼠（B缺陷的CBA／N，T缺陷的BALB／c裸鼠，T，B缺陷的C.B-17 SICD小鼠及免疫重建的SCID小鼠。免疫正常的BALB／c作为对照组）皮下、肝内、腹腔，观察其生长特性。结果 BALB／c小鼠和用BALB／c外周淋巴细胞免疫重建的SCID（BALB／c-PBL-SCID)不成瘤；CBA/N小鼠随接种数量和途径不同而有不同的表现；BALB／c裸鼠，SCID小鼠和CBA／N小鼠外周淋巴细胞重建的SCID（CBA／N－PBL－SCID）100％成瘤。结论 SCID小鼠是建立肝癌模型的最佳小鼠，也是进行肿瘤免疫研究最佳模型动物；T细胞在异种瘤移植排斥中起主要作用。     

肿瘤相关抗原与白细胞介素2并用的抗瘤作用

本文以艾氏腹水瘤接种于 C57BL/6小鼠皮下为转移瘤模型。接种前先用肿瘤相关抗原(TAA)免疫,可明显增强白细胞介素2(IL-2)的抑瘤效果。三批每组45只小鼠的实验结果表明,对照组肿瘤逃逸率6.7%,IL-2治疗组17.8%,TAA 免疫和 IL-2并用组为37.8%。每只小鼠皮下接种瘤细胞2×10~6,一周后对照组有40%、IL-2组有30%、TAA IL-2组有20%的小鼠长出了肿瘤。停止治疗三周后 IL-2组和 TAA IL-2组肿瘤体积分别相当于对照组的0.56±0.10和0.34±0.23;停止治疗40天后,三组肿瘤平均重量分别为1.12g、0.64g和0.15g。IL-2组与对照组相比 p<0.001;TAA IL-2组与 IL-2组之间 p<0.001。过继注射 TAA 免疫小鼠的淋巴细胞,在推迟肿瘤出现、阻止肿瘤的初期生长和延长小鼠存活方面有明显而短暂的作用,但作用消失后有的肿瘤发展更快。     

CBA/N小鼠肝癌移植瘤的建立及重建SCID免疫的B淋巴细胞抗癌作用

目的: 研究CBA/N,nude,SCID小鼠建立人肝癌模型和重建SCID免疫的特点,初步探讨B淋巴细胞及其抗体对肝癌细胞生长的排斥作用.方法: 将体外培养的人肝癌细胞接种到B细胞缺陷的CBA/N,T细胞缺陷的BALB/c-nu,T,B细胞缺陷的SCID小鼠及免疫重建的SCID小鼠中,观察瘤细胞生长特点;取实验小鼠血清,测定荷瘤鼠抗体Ig含量的变化,取小鼠血清与肝癌细胞作抗原抗体凝集试验.结果: CBA/N和用BALB/c小鼠外周血淋巴细胞重建的SCID(B-PBL-SCID)小鼠不成瘤,nude,SCID和用CBA/N外周血淋巴细胞重建的SCID (C-PBL-SCID)小鼠100%成瘤;有B淋巴细胞的实验鼠(包括B-PBL-SCID)测到的Ig达到mg/mL水平,血清能与肝癌产生凝集反应.结论: SCID小鼠是建立肿瘤模型和免疫重建及其肿瘤免疫研究的理想的实验动物;B淋巴细胞及其产生的抗体在抗肿瘤中起着重要的作用.