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101.
We have constructed PPD monoclonal antibody heteroconjugates specific for a tumour-associated antigen of C57BL/6 melanomas or for human complement component C3d fixed de novo to murine fibrosarcoma cells (MC6A). The ability of our heteroconjugates to target CD4+ PPD-reactive T cells against the appropriate tumour targets was then determined in vitro. Heteroconjugate-treated B16-F10 and MC6A tumour targets were both able to present PPD to the specific T cells, resulting in activation and concomitant lymphokine secretion. Secreted lymphokines were then demonstrated to cause significant tumour cytolysis and cytostasis in vitro. Preliminary experiments in vivo suggest that this targeting system may provide the basis for a future immunotherapeutic strategy.  相似文献   
102.
R. Djurup 《Allergy》1985,40(7):469-486
The purpose of this paper is to discuss the methodological difficulties in quantitation of human IgG subclass antibodies to allergens, to describe the subclass nature of the IgG antibody response in patients undergoing allergen-specific immunotherapy, and to discuss the possible immunological functions and clinical significance of allergen-specific IgG antibodies of different subclasses. Based on results obtained by use of assays with documented specificity it is concluded that the IgG antibody response during allergen-specific immunotherapy is IgG1 and IgG4 restricted, although low levels of IgG2 and IgG3 antibodies to some allergens may occur. In most patients the early IgG antibody response is IgG1 dominated and the late IgG4 dominated. A too early or too pronounced IgG4 dominated antibody response seems to indicate a poor clinical outcome of immunotherapy with inhalant allergens, whereas a pronounced early IgG1 antibody production has been found to be associated with a decrease in synthesis of IgE antibodies to an insect venom. It is therefore proposed that an early IgG1 dominated response is necessary to induce suppression of the ongoing IgE antibody production, which in its turn may be a prerequisite for long-lasting clinical effect. The possibility of induction of an early IgG1 dominated response in every patient by use of alternative immunotherapy procedures is discussed.  相似文献   
103.
目的:评估特瑞普利单抗联合舒尼替尼治疗晚期肾细胞癌的疗效与安全性。方法:回顾性分析2020年1月—2022年3月海军军医大学第二附属医院接受特瑞普利单抗联合舒尼替尼治疗的25例晚期肾癌患者临床资料,其中男21例,女4例,中位年龄为59 (33~80)岁。25例患者病理类型均为透明细胞癌,其中2例为TFE3融合基因相关肾癌,1例部分肉瘤样变,25例患者均发生局部进展或远处转移。评价其生存获益和相关不良反应发生情况。结果:中位随访时间11.0(2.5~24)个月,25例患者均可评价疗效,总体人群ORR 36.0%,DCR 84.0%,9例患者部分缓解,12例患者病情稳定,4例患者疾病进展,中位PFS 12.7个月(95%置信区间:10.7~14.7),中位OS尚未达到。治疗总体不良反应发生率为88.0%,常见不良反应包括皮疹、腹泻、手足皮肤反应、高血压等,90%的不良反应为1~2级。  相似文献   
104.
Summary The therapeutic efficacy and toxicity of three biological response modifiers,Corynebacterium parvum (Cp), Chinese blister beetle extract (CBBE), recombinant human IL-1 (rhIL-1), used alone or in combination with chemotherapy or radiotherapy, were investigated in the intracerebral (ic) rat 9L brain tumor model. Used alone, Cp (2mg/rat, ip plus 70g/rat, ic), CBBE (5l of an ethanol extract, ic), or IL-1 (lg/rat, ic or 1g/rat × 3, q 3 d, ic), had no effect on animal survival compared to the untreated or saline treated controls. When combined with chemotherapy or radiotherapy, the three immunotherapeutic agents did not show any additive effects on survival compared to that observed with systemic BCNU (12mg/kg), local ic bleomycin (0.25 unit), or local radiotherapy (16 Gy). While ic IL-1 did not produce evident toxicity, there was fatal toxicity caused by ic Cp or CBBE treatment in a few animals. The combination of Cp and bleomycin produced severe neurotoxicity, resulting in the early death of animals. This study demonstrates a lack of efficacy of the nonspecific immune adjuvants IL-1, Cp or CBBE, used either alone or combined with cytotoxic chemotherapy or radiotherapy, in this rat brain tumor model.  相似文献   
105.
Summary An immunoconjugate composed of natural interferon (nIFN) bound in a noncleavable fashion to a monoclonal antibody (MoAb) recognizing a breast epithelial membrane mucin (Mc5) was used to treat xenografts of a human mammary carcinoma cell line (MCF-7) growing in nude mice. The immunoconjugate (nIFN/Mc5) was administered as 20 intralesional (i.l.) injections to 1 of 2 xenografts in each animal. It was found that nIFN/Mc5 produced a significant enhancement of the growth inhibitory actions of nIFN on the injected tumors. Further enhancement was obtained when nIFN or nIFN together with Mc5 (at a dose 10 times larger than that present in nIFN/Mc5) were added to the immunoconjugate. Biodistribution experiments showed that the uptake of125I-nIFN/Mc5 by the tumors was greater and its elimination slower than for125I-nIFN alone or conjugated to irrelevant mouse IgG1. In addition, the immunoconjugate up-regulated the antigenic expression of a breast epithelial membrane mucin by the carcinoma cells, an up-regulation which was not significantly different from that produced by nIFN alone. The contralateral noninjected tumors exposed to systemic levels of the immunoconjugate showed an enhancement of antitumor effects, but to a lesser extent than the injected tumors. These findings suggest that the enhancement of the growth inhibitory action of the immunoconjugate was related to the specific binding of Mc5 which targeted the IFN to the carcinoma cells and impeded its elimination. It is likely that the targeting was favored by the IFN-mediated up-regulation of antigenic expression by the carcinoma cells, thereby producing a cascade of interrelated effects. The results of this study point out the feasibility and potential usefulness of IFN treatment by means of immunoconjugates as well as the worth of pursuing and improving this form of therapy.  相似文献   
106.
Summary The study was initiated as an in vitro approach to the situation existing during intravesical bacillus Calmette-Guerin (BCG) instillation in patients with superficial bladder cancer. Cytokine secretion of a human bladder carcinoma cell line T24 treated with BCG was investigated. A 24-h treatment of T24 cells with BCG resulted in a tenfold higher secretion of interleukin-6 (IL-6) and tumor necrosis factor alpha (TNF) when compared with T24 cells treated with Escherichia coli, Streptococcus faecalis or a cell wall preparation of Nocardia rubra (N-CWS). No secretion of IL-1 and IL-2 was detected. Pre-exposing T24 cells to BCG for various periods of time indicated that a minimum exposure time of 0.5–1 h was required to upregulate IL-6 and TNF production. Extending the BCG pre-exposure time to 2 and 3 h further increased the rate of cytokine production. No significant difference was found, however, between the rate of secretion initiated after a 2-h or 3-h pre-exposure period. The amounts of these cytokines secreted in the presence of BCG-conditioned medium did not differ significantly from the constitutively secreted amounts, excluding an effect of products possibly secreted by BCG on the upregulation of IL-6 and TNF. In addition, upregulation of cytokine production appeared to be dependent on the concentration of BCG. The results suggest that cytokines may be produced by urothelial tumor cells after intravesical instillation in patients with superficial bladder cancer, which may play a role in the mode of action of BCG.  相似文献   
107.
Objective: To study the treatment of experimental metastatic lung carcinoma by intratracheal injection of IL-18 gene recombinant adenovirus. Methods: (1)The mouse IL-18 mRNA was detected by RT-PCR, and the concentration of 1L-18 and associated cytokines in lung lavages and blood were determined by ELISA at different time points after intratracheal injection of IL-18 recombinant adenovirus. (2)The lung metastasis nodes, mouse survival periods and survival rates were evaluated. NK activity and CTL activity were determined by 51Cr 4 h release method. Results: (1)IL-18 mRNA was detectable in lung tissue 6 h after intratracheal use of IL-18 recombinant adenovirus, and the concentration of IL-18 in lung lavage was higher than that in peripheral blood. Neither IL-18 mRNA nor IL-18 was detectable in control group. (2) Intmtmcheal use of IL-18 recombinant adenovirus resulted in increased CTL and NK activity, longer survival time and higher survival rates compared with the control group, showing significant therapeutic effect on experimental lung metastasis. Conclusion: Intratracheal use of adenovirus vector containing IL-18 gene has therapeutic effect on the lung metastasis, denoting that gene therapy of lung diseases could be applied through airway directly with recombinant adenovirus.  相似文献   
108.
目的: 分析抗N-甲基-D-天冬氨酸受体(N-methyl-D-aspartate receptor,NMDAR)脑炎患儿的临床特点及 预后,为临床早期识别本病提供依据。方法: 回顾性分析2015 年1 月至2018 年3 月在中南大学湘雅二医院儿科住院 的42 例抗NMDAR脑炎患儿的临床资料及随访情况,总结其临床特点、治疗效果及预后情况。结果: 42 例患儿中男 15 例(35.7%),女27 例(64.3%),男女比例1?1.8,年龄(9.20±4.66)岁(最小4 个月,最大17 岁)。首发症状以癫痫发作 (47.6%,20/42)和精神行为异常(35.7%,15/42)最为常见;患儿在病程中累积出现精神行为异常(36/42,85.7%)、癫痫 发作(36/42,85.7%)、言语障碍(32/42,76.2%)、运动障碍(28/42,66.7%)、意识障碍(28/42,66.7%)、自主神经功能 紊乱(26/42,61.9%)及睡眠障碍(24/42,57.1%)等症状。42 例患儿脑脊液抗NMDAR抗体均为阳性;50.0%(21/42)的患 儿头颅MRI检查结果异常,病变累及顶叶、额叶、颞叶、枕叶、基底节及视神经等部位,1 例患儿病变累及视神经 合并髓鞘少突胶质细胞糖蛋白(myelin oligodendrocyte glycoprotein,MOG)抗体阳性;40 例患儿行脑电图检查,92.5% (37/40)出现异常,以弥漫性慢波为主要表现,1 例可见δ 刷;合并肠系膜畸胎瘤1 例,占2.4%(1/42)。出院时mRS评 分为2.14±1.46,较住院期间最高mRS评分(3.88±1.38)显著降低(P<0.05),疗效显著;随访3~39 个月,出院后3 个月 时mRS评分仅为0.81±1.29,与出院时mRS评分比较仍有显著改善,其中76.2%(32/42)mRS评分≤2,预后良好;4.8% (2/42)的患儿复发,无死亡病例。开始免疫治疗时间和病程中最高mRS评分是影响预后的因素,开始免疫治疗时间越 早、病程中mRS评分越低,预后越好。结论: 癫痫发作、精神行为异常、运动障碍、言语障碍及自主神经功能紊乱 是儿童抗NMDAR脑炎的常见临床表现;免疫治疗效果显著,开始免疫治疗的时间和病情严重程度是影响预后的重 要因素;抗NMDAR脑炎可合并其他自身抗体,其临床意义及机制有待深入研究。  相似文献   
109.
CD3AK细胞治疗头颈部恶性肿瘤的近期疗效观察*   总被引:1,自引:0,他引:1  
目的:观察CD3AK在头颈部恶性肿瘤的综合治疗中的效果.方法:81例头颈部恶性肿瘤分成CD3AK治疗组(n=42)和对照组(n=39),治疗组有术前、术后单用CD3AK细胞治疗,亦有术前化疗加用CD3AK细胞治疗;对照组有术前、术后单用LAK细胞治疗,有术前单用化疗.治疗前后检查肿瘤缩小情况,并检测外周血T细胞亚群和血清可溶性白细胞介素2受体水平.结果:CD3AK对舌癌的治疗效果最好,治疗组与对照组比较有显著性差异(P<0.01);其次为喉癌与甲状腺癌,与对照组相比,有显著性差异(P<0.05);再次为腮腺腺癌.各项免疫指标:CD3、CD4、CD8及CD4/CD8均有不同程度的提高;sIL-2R水平有所下降.结论:CD3AK细胞治疗作为新的肿瘤过继免疫治疗,在头颈部恶性肿瘤的综合治疗中,毒副反应较少,疗效满意,有很好的推广前景.  相似文献   
110.
Non-small cell lung cancer (NSCLC) is one of the most common types of cancer in the world and has a 5-year survival rate of ~20%. Immunotherapies have shown promising results leading to durable responses, however, they are only effective for a subset of patients. To determine the best therapeutic approach, a thorough and in-depth profiling of the tumour microenvironment (TME) is required. The TME is a complex network of cell types that form an interconnected network, promoting tumour cell initiation, growth and dissemination. The stroma, immune cells and endothelial cells that comprise the TME generate a plethora of cytotoxic or cytoprotective signalling pathways. In this review, we discuss immunotherapeutic targets in NSCLC tumours and how the TME may influence patients' response to immunotherapy.  相似文献   
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