Experimental study of specific immunotherapy induced by H22 autologous tumor as whole tumor cell vaccine

This study explores the novel H22 whole-cell vaccine of active specific immunotherapy in the treatment of hepatocellular carcinoma. H22 hepatoma tumor vaccine modified by human interleukin-2 (hIL-2) and mouse granulocyte-monocyte colony-stimulating factor (mGM-CSF) fusion gene was prepared to study its specific anti-tumor immunity. Mice were inoculated by these vaccines. Then tumor cells were injected into mouse models. The ⁵¹Cr release assay was used to examine the cytotoxicities of the splenocytes to H22 hepatoma cells in immunized mice, tumor-bearing mice and control mice. The blood was needed to test the level of IL-10 and interferon (IFN)-γ in serum. Survival time of mice was calculated. Specific cytotoxicity rate of splenocytes from the immunized mice to H22 cancer cell was 38%, significantly higher than 13.6% in the tumor-bearing group, 7.5% in the control group, and 9.1% in S180 cells (p < 0.05). Serum IFN-γ in the immunized group was significantly increased compared with other groups (p < 0.01), and serum IL-10 in the immunized group was significantly decreased compared with other groups(p < 0.01). The survival time of the transgenic vaccinated group was significantly longer.     

肿瘤免疫治疗护理相关研究的关键词可视化分析

目的 对国内外肿瘤免疫治疗护理研究的现状与热点进行分析,为后续更好地提高肿瘤免疫治疗护理服务质量提供参考依据。方法 检索2002年1月—2022年7月中国知网、万方数据知识服务平台、中国生物医学文献服务系统、维普期刊官网、Web of Science核心合集数据库,共纳入中文文献434篇,英文文献500篇。通过CiteSpace软件对相关文献的发文量、作者合作网络进行分析,对关键词进行共现分析和聚类分析。结果 国内外发文量呈上升趋势,作者合作关系有待加强,关键词聚类结果集中在免疫治疗方法及应用癌种、免疫治疗相关不良事件、患者报告结局3个方面。国外研究趋势倾向于预后,国内研究趋势倾向于质性研究。结论 当前肿瘤免疫治疗护理研究快速发展,国内需加强合作并积极与国外交流。肿瘤免疫治疗的护理热点集中在不同免疫治疗的护理特点、免疫治疗相关不良事件的分级管理、改善患者报告结局。肿瘤免疫治疗患者的预后及相关质性研究是新兴领域,有待进一步深入研究。     

Self-tolerance to the murine homologue of a tyrosinase-derived melanoma antigen: implications for tumor immunotherapy

The human tyrosinase-derived peptide YMDGTMSQV is presented on the surface of human histocompatibility leukocyte antigen (HLA)-A*0201(+) melanomas and has been suggested to be a tumor antigen despite the fact that tyrosinase is also expressed in melanocytes. To gain information about immunoreactivity and self-tolerance to this antigen, we established a model using the murine tyrosinase-derived homologue of this peptide FMDGTMSQV, together with transgenic mice expressing the HLA-A*0201 recombinant molecule AAD. The murine peptide was processed and presented by AAD similarly to its human counterpart. After immunization with recombinant vaccinia virus encoding murine tyrosinase, we detected a robust AAD-restricted cytotoxic T lymphocyte (CTL) response to FMDGTMSQV in AAD transgenic mice in which the entire tyrosinase gene had been deleted by a radiation-induced mutation. A residual response was observed in the AAD(+)tyrosinase(+) mice after activation under certain conditions. At least some of these residual CTLs in AAD(+)tyrosinase(+) mice were of high avidity and induced vitiligo upon adoptive transfer into AAD(+)tyrosinase(+) hosts. Collectively, these data suggest that FMDGTMSQV is naturally processed and presented in vivo, and that this presentation leads to substantial but incomplete self-tolerance. The relevance of this model to an understanding of the human immune response to tyrosinase is discussed.     

Internalization of MWCNTs by microglia: possible application in immunotherapy of brain tumors

There is a pressing need for new therapeutic, diagnostic, and drug delivery approaches for treating brain cancers. Nanotechnology offers a new method for targeted brain cancer therapy and could play a major role in gene and drug delivery. The goals of our study were to visualize in vitro ingestion, cytotoxicity, and loading capacity of Multi-Walled Carbon Nanotubes (MWCNTs) in microglia. Furthermore, we investigated internalization differences between microglia and glioma cells. BV2 microglia and GL261 glioma cells were incubated with MWCNTs, which were synthesized through catalytic chemical vapor deposition technique. Real-time RT-PCR, cell proliferation analysis, siRNA and DNA loading, electron microscopy, and flow cytometry were performed. We demonstrated that MWCNTs do not result in proliferative or cytokine changes in vitro, are capable of carrying DNA and siRNA and are internalized at higher levels in phagocytic cells as compared to tumor cells. This study suggests MWCNTs could be used as a novel, non-toxic, and biodegradable nano-vehicles for targeted therapy in brain cancers. Further studies are needed to demonstrate the full capacity of MWCNTs as nanovectors.     

Complete regression of large solid tumors using engineered drug-resistant hematopoietic cells and anti-CD137 immunotherapy

Combining chemotherapy and immunotherapy is problematic because chemotherapy can ablate the immune responses initiated by modulators of the immune system. We hypothesized that protection of immunocompetent cells from the toxic effects of chemotherapy, using drug resistance gene therapy strategies, would allow the combined use of chemotherapy and immunotherapy. In wild-type mice, the antitumor effectiveness of an immunotherapy regimen employing an agonistic anti-CD137 antibody is diminished with escalating doses of the antifolate trimetrexate (TMTX). Using retroviral gene transfer of a mutant form of dihydrofolate reductase (L22Y-DHFR), hematopoietic stem cells were genetically engineered to withstand the toxic effects of TMTX. Mice transplanted with L22Y-DHFR-modified bone marrow were then challenged with AG104 sarcoma cells and treated with TMTX only, anti-CD137 only, or a combination of chemotherapy and immunotherapy. Although tumor burden was transiently decreased during TMTX administration, no mice treated with TMTX alone survived the tumor challenge, whereas approximately 40% of transplanted mice treated with anti-CD137 alone survived. However, 100% of mice survived with complete tumor regression after transplantation with L22Y-DHFR-transduced bone marrow followed by combined treatment with TMTX and anti-CD137. In addition, adoptive transfer of splenocytes from cured mice extended the survival of tumor- bearing animals by approximately 3 weeks compared with controls. Therefore, protection of the hematopoietic system can allow for the combined administration of chemotherapy and immunotherapy, which results in complete tumor clearance.     

Tumor-specific immunity and antiangiogenesis generated by a DNA vaccine encoding calreticulin linked to a tumor antigen.

Antigen-specific cancer immunotherapy and antiangiogenesis have emerged as two attractive strategies for cancer treatment. An innovative approach that combines both mechanisms will likely generate the most potent antitumor effect. We tested this approach using calreticulin (CRT), which has demonstrated the ability to enhance MHC class I presentation and exhibit an antiangiogenic effect. We explored the linkage of CRT to a model tumor antigen, human papilloma virus type-16 (HPV-16) E7, for the development of a DNA vaccine. We found that C57BL/6 mice vaccinated intradermally with CRT/E7 DNA exhibited a dramatic increase in E7-specific CD8(+) T cell precursors and an impressive antitumor effect against E7-expressing tumors compared with mice vaccinated with wild-type E7 DNA or CRT DNA. Vaccination of CD4/CD8 double-depleted C57BL/6 mice and immunocompromised (BALB/c nu/nu) mice with CRT/E7 DNA or CRT DNA generated significant reduction of lung tumor nodules compared with wild-type E7 DNA, suggesting that antiangiogenesis may have contributed to the antitumor effect. Examination of microvessel density in lung tumor nodules and an in vivo angiogenesis assay further confirmed the antiangiogenic effect generated by CRT/E7 and CRT. Thus, cancer therapy using CRT linked to a tumor antigen holds promise for treating tumors by combining antigen-specific immunotherapy and antiangiogenesis.     

构建重组肿瘤基因疫苗对肿瘤进展及生存率影响的实验结局

目的 利用 P815肿瘤动物模型观察 IL- 12对肿瘤动物模型抗肿瘤作用的效应. 方法 将小鼠肥大细胞瘤 P815特异抗原基因 P1A克隆到真核表达质粒 pCI- neo中;用 P815细胞对 DBA/2小鼠右腹侧皮下注射,构建 P815小鼠肿瘤模型;以重组基因疫苗单独或与鼠 IL- 12真核表达质粒一起肌肉注射,观察肿瘤的消长、特异细胞毒 T淋巴细胞激活和抗体的生成情况. 结果 重组基因疫苗在体外有很好的表达,注射后细胞毒性 T淋巴细胞(CTL)的杀伤效率为 40%, IL- 12共注射的 CTL杀伤效率达到 60%.免疫后, 30%小鼠的肿瘤出现消退;同 IL- 12共注射则有 50%的小鼠的肿瘤出现消退.两种情况下都不能检测到任何特异抗体的产生. 结论 长期存在的 IL- 12可以持续刺激机体细胞免疫,使肿瘤的生存环境持续恶化,从而达到治疗肿瘤的目的.     

T cell-mediated immunosuppression as an obstacle to adoptive immunotherapy of the P815 mastocytoma and its metastases

Progressive growth of the P815 mastocytoma in semisyngeneic mice evokes the generation of a T cell-mediated mechanism of immunosuppression that inhibits the capacity of passively transferred, tumor-sensitized T cells from regressing this tumor in recipient mice. This conclusion is based on two findings: (a) that it is possible to demonstrate adoptive T cell-mediated regression of established tumors, but only if the tumors are growing in T cell-deficient recipients, and (b) that adoptive T cell-mediated regression of tumors in these recipients can be inhibited by the infusion of splenic T cells from T cell-intact, tumor-bearing donors. The results of additional experiments designed to measure the effect of decreasing the number of suppressor cells and the time that they are infused, relative immune cells, indicate that the function of suppressor cells in this model is to inhibit the replication of passively transferred immune T cells. The results obtained with the P815 mastocytoma are similar to those obtained previously with a chemically induced fibrosarcoma. They show, in addition, that passively transferred immune cells are capable of destroying already seeded metastases in T cell-deficient recipients.     

Spontaneous drainage of a large cystic tumor

A case is described of a 58 year old male who presented with a large mass on the left side of the abdomen which was found to be cystic by ultrasound. A presumptive diagnosis of pancreatic pseudocyst was made. Shortly thereafter, the mass drained spontaneously further suggesting this diagnosis. At surgery a month later, however, the mass was found to be a metastic leiomyosarcoma with cystic degeneration that had eroded into the gastric wall. This case serves to illustrate that cystic abdominal masses, even ones that drain spontaneously into the gastrointestinal tract, may not be pancreatic pseudocysts.     

Active specific immunotherapy of melanoma with a GM3 ganglioside-based vaccine: a report on safety and immunogenicity

A novel cancer vaccine was obtained by combining GM3 ganglioside with Neisseria meningitidis outer membrane protein complex to obtain very-small-size proteoliposomes (GM3/VSSP). The authors report the results of a phase 1 study of intramuscular administration of GM3/VSSP/Montanide ISA 51 to patients with metastatic melanoma. Twenty-six patients were included in three dose-level cohorts of 120, 240, and 360 mug. The first five doses (induction phase) were given at 2-week intervals, and the remaining four doses were given monthly. Patients were evaluated for dose-related toxicities and antitumor effects. In addition, serum and peripheral blood mononuclear cells were obtained at baseline and throughout treatment to evaluate humoral and cellular immune responses. One episode of severe hypotension and fever was observed in a patient included at the highest dose level. Other toxicities consisted of local reactions at the site of injection and mild fever and chills. Five doses of GM3/VSSP induced an anti-GM3 IgM response in 44% of patients. Serum reactivity was also observed against melanoma cell lines and tumor biopsies. GM3/VSSP was shown to induce very strong in vitro IFNgamma secretion in all evaluated melanoma patients. Furthermore, in one patient IFNgamma secretion was shown to be GM3-specific. A 62% reduction of a mediastinal mass was documented in one patient (partial response), while a second patient benefited from initial disease stabilization followed by tumor reduction in nonmeasurable soft tissue lesions accompanied by vitiligo.     

Regulation of blood-brain tumor barrier permeability by calcium-activated potassium channels

The blood-brain tumor barrier (BTB) limits the delivery of therapeutic drugs to brain tumors. We demonstrate in a rat brain tumor (RG2) model an enhanced drug delivery to brain tumor following intracarotid infusion of bradykinin (BK), nitric oxide (NO) donors, or agonists of soluble guanylate cyclase (sGC) and calcium-dependent potassium (K(Ca)) channels. We modulated K(Ca) channels by specific agonists and agents that produce NO and cGMP in situ to obtain sustained enhancement of selective drug delivery to brain tumors. Intracarotid infusion of BK or 1,3-dihydro-1-[2-hydroxy-5-(trifluoromethyl)phenyl]-5-(trifluoromethyl)-2H-benzimidazol-2-one (NS-1619) significantly enhanced BTB permeability (K(i)) to [(14)C]alpha-aminoisobutyric acid in the brain tumor area but not in normal brain tissue. The K(i) increase achieved by BK, NS-1619, NO donors, or the sGC activator 3-(5'-hydroxymethyl-2'furyl)-1-benzylindazole (YC-1) was significantly attenuated when coinfused with a K(Ca) channel antagonist, iberiotoxin. Immunoblot and immunolocalization studies demonstrate overexpression of K(Ca) channels in tumor cells and capillaries compared with normal brain. The potentiometric assays demonstrate the functional activity of K(Ca) channels in rat brain endothelial and glioma cells. Additionally, we show that BK and NS-1619 significantly increased the density of transport vesicles in the cytoplasm of brain tumor capillary endothelia and tumor cells. The cleft indices and cleft area indices in rat tumor capillaries were significantly higher than in normal brain capillaries, and BK infusion did not alter these indices. These data demonstrate that the cellular mechanism for K(Ca) channel-mediated BTB permeability increase is due to accelerated formation of pinocytotic vesicles, which can transport drugs across BTB. We conclude that K(Ca) channels serve as a convergence point in the biochemical regulation of BTB permeability.     

A recombinant E. coli vaccine to promote MHC class I-dependent antigen presentation: application to cancer immunotherapy

We have examined the potential of recombinant Escherichia coli expressing listeriolysin O (LLO) to deliver tumour antigens to dendritic cells (DCs) for cancer immunotherapy. Using OVA as a model tumour antigen, we have shown in murine DCs that E. coli expressing cytoplasmic LLO and OVA proteins can deliver the OVA K(b)-restricted epitope SIINFEKL for MHC class I presentation. In contrast, when E. coli expressing OVA alone were used, MHC class II presentation of the OVA 323-339 I-A(b)-restricted peptide was predominant. When injected in vivo, DCs pulsed with E. coli expressing LLO and OVA induced production of cytotoxic T-lymphocytes capable of lysing an OVA-expressing melanoma cell line (B16-OVA) and resulted in suppression of tumour growth following challenge with B16-OVA. Immunisation of mice by direct injection of E. coli LLO/OVA provided a more potent anti-tumour response, resulting in complete protection in 75% of mice. Injection of live bacteria was not necessary as immunisation with paraformaldehyde-fixed E. coli LLO/OVA provided an even stronger anti-tumour response against B16-OVA. Altogether, our data highlight the potential of this system as a novel and efficient strategy for tumour immunotherapy.     

应用脂肪抽吸术治疗巨大脂肪瘤的护理

手术切除治疗脂肪瘤 ,术后遗留瘢痕 ,影响体表皮肤的外观美 ,用脂肪抽吸法治疗脂肪瘤可弥补手术之不足。总结了应用脂肪抽吸术治疗巨大脂肪瘤 3例患者的护理体会 ,着重于脂肪瘤患者的心理特点及护理和预防血肿发生的护理     

B7.1/NHS76: a new costimulator fusion protein for the immunotherapy of solid tumors

Tumor evasion from immune surveillance is due to the anergic status of tumor-infiltrating lymphocytes, especially T cells. Inappropriate or absent expression of costimulatory molecules such as B7.1 and B7.2 lead to anergy and apoptosis of tumor-infiltrating T cells. To reverse this situation, a tumor-targeted fusion protein, human B7.1/NHS76, was generated by molecular engineering, which retains both the costimulatory activity of B7.1 and the tumor-targeting ability of NHS76 antibody. NHS76 is a human tumor necrosis therapy monoclonal antibody derived from phage display, and is capable of binding intracellular antigens, which are accessible and abundant in necrotic regions of tumors. As human B7.1 can interact functionally with murine B7.1 counter-receptors, the immunotherapeutic potential of this fusion protein was tested in 3 mouse tumor models (Colon 26, RENCA, and MAD109), and animal studies showed a 35% to 55% reduction in tumor volume. To modulate the immune inhibitory microenvironment in tumors, naturally occurring CD4+ CD25+ Treg cells were depleted by cytotoxic CD4 or CD25 antibodies. Combination therapy with anti-Treg and B7.1/NHS76 produced complete regression of established tumors and was associated with increased effector T-cell infiltration in tumors. Rechallenge experiments performed 3 months after mice attained complete remission by combination therapy showed that immunologic memory was established by these treatments. These studies indicate that the targeting of B7.1 to necrotic areas of tumors, where both the release of tumor antigens and infiltrating lymphocytes are prevalent, may be a new approach for the immunotherapy of solid tumors. Our results also suggest that the manifestation of immune-inhibitory factors such as the presence of Treg cells at the tumor site and associated draining lymph nodes may be a major cause for immune system failure to eradicate solid tumors.     

Thinly disguised contempt: a barrier to excellence

Many elements in contemporary leadership and management convey contempt for employees. "Thinly disguised contempt," a concept introduced by Peters and Austin in A Passion For Excellence, explains many barriers to the achievement of excellence in corporations across disciplines. Health care executives and managers can learn from the errors of corporate management and avoid replicating these errors in the health care industry.