Enhanced immunogenicity and antitumour effects with heterologous prime-boost regime using vaccines based on MG7-Ag mimotope of gastric cancer

MG7-Ag, gastric cancer-associated antigen, has been shown to be immunogenic and has been used as marker molecule for prognosis. In a previous study, we developed an oral DNA vaccine based on MG7-Ag mimotope. However, we failed to detect cellular immune response using the oral MG7-Ag mimotope DNA vaccine. To induce significant T cell response, we developed a recombinant adenovirus vaccine based on MG7-Ag mimotope and evaluated the efficacy and protective effects of heterologous prime-boost immunization protocol with an oral DNA vaccine previously developed. We found that both vaccines were able to elicit a significant humoral response against MG7-Ag, while the highest serum titre MG7 antibody was detected in mice immunized with the heterologous prime-boost immunization protocol. Enzyme-linked immunospot (ELISPOT) assay demonstrated that the heterologous prime-boost immunization strategy was more efficient in inducing T cell response than the homologous prime-boost strategy. In the tumour challenge assay, 2 of 5 mice immunized with the heterologous prime-boost protocol were tumour free, while none of the mice in homologous prime-boost groups or control groups was tumour free. Those tumour-bearing mice in the heterologous prime-boost regime had smaller tumour masses than their counterparts in the homologous prime-boost groups or control groups. Therefore, our study suggests that vaccines against MG7-Ag induce significant immune response against gastric cancer, and that the heterologous prime-boost protocol using different types of vaccines could achieve better protective effect than the homologous prime-boost protocol.     

三种移植骨材料修复骨缺损能力的比较研究

目的 研究单纯异种无机骨，复合骨髓异种无机骨以及自体皮质骨修复骨缺损的能力。方法 取健康6月龄纯系新西兰大白兔22只，制作兔桡骨节段性骨缺损（1.5cm)模型。根据植入物的不同，随机分为自体皮质骨组（10肢），单纯异种无机骨组（10肢），复合骨髓的异种无机骨组（20肢）和空白对照组（4肢），术后2、4、6、8、12周进行放射线片和组织学观察。结果 单纯异种无机骨植入组，直至12周，仍为缓慢的骨传导过程，周边骨小梁向无机骨内爬行替代，异种无机骨内大部分为纤维组织，只有少数中心区域有新骨形成，而复合骨髓的异种无机骨植入后2周即有新骨形成，8周无机骨基本吸收替代完毕，12周髓腔形成，塑形改造，基本相关于自体皮质骨移植的融合速度，结论 复合骨髓的异种无机骨的成骨能力明显优于单纯异种无机骨，与自体皮质骨相当。     

Different effects of BCG strains – A natural experiment evaluating the impact of the Danish and the Russian BCG strains on morbidity and scar formation in Guinea-Bissau

BackgroundDifferent Bacillus Calmette-Guerin (BCG) vaccine strains may have different non-specific effects. We assessed the effect of two BCG strains (Danish and Russian) on childhood morbidity and BCG scarification in Guinea-Bissau.MethodsDuring 2011–2013, infants in the Bandim Health Project’s urban study area received the Danish or Russian BCG in a natural experiment. Health center consultations were registered at point of care and scar status and size at age 4½ months. We assessed the effect of strain on consultation rates between vaccination and age 45 days in Cox proportional hazards models. Scar prevalence and size were compared using binomial regression and ranksum tests.ResultsAmong 1206 children, 18% received Danish BCG (n = 215) and 82% Russian BCG (n = 991). The adjusted hazard ratio (aHR) for consultations was 0.94 (95% CI 0.60–1.46) for Danish BCG compared with Russian BCG. Girls vaccinated with Danish BCG tended to have lower consultation rates compared with girls vaccinated with Russian BCG (aHR 0.56 (0.25–1.24)), whereas the effect was opposite for boys (aHR 1.24 (0.74–2.11)), p = 0.09. Children vaccinated with Danish BCG were more likely to develop a scar (97%) than children vaccinated with Russian BCG (87%), the relative risk (RR) being 1.11 (1.06–1.16). The effect was stronger in girls, and BCG scar size was larger among infants vaccinated with the Danish strain.ConclusionBCG strain influences scar prevalence and scar size, and may have sex differential effects on morbidity. BCG strains are currently used interchangeably, but BCG scarring has been linked to subsequent survival. Hence, more research into the health effects of different BCG strains is warranted. Small adjustments of BCG production could potentially lower childhood morbidity and mortality at low cost.     

CTLA4-Ig和IL-4诱导异种骨移植免疫耐受的体外研究

目的探讨CTLA4Ig和IL4在诱导异种骨移植免疫耐受中的作用。方法反应细胞为BALB/c小鼠脾淋巴细胞,刺激细胞为新西兰白兔血淋巴细胞,刺激抗原为兔骨上清液。采用经典的混合淋巴细胞培养法及骨上清液与淋巴细胞混合培养法作为异种骨移植的体外实验模型。在各培养液中分别加入CTLA4Ig、IL4及两者联合应用,通过测定其3HTdR掺入率,观察不同细胞因子对刺激淋巴细胞增殖的影响。结果1细胞刺激组CTLA4Ig和IL4均对淋巴细胞增殖有显著抑制作用P<0.001),CTLA4Ig与IL4联合应用并未显示出比CTLA4Ig单独应用更为明显的细胞增殖抑制作用(P>0.05)。2骨上清液刺激组:CTLA4Ig对细胞增殖无抑制作用(P>0.05),而IL4则有较为显著地细胞增殖抑制作用(P<0.05);CTLA4Ig与IL4联合应用也未产生比单独应用IL4更为明显的细胞增殖抑制作用(P>0.05)。结论CTLA4Ig对由细胞刺激产生的淋巴细胞增殖抑制效果较好,而IL4则对骨上清液刺激的细胞增殖抑制作用更好;CTLA4Ig与IL4联合应用并未产生协同抑制作用。     

华支睾吸虫线粒体苹果酸脱氢酶基因的原核表达及重组蛋白的功能鉴定

目的克隆肝吸虫线粒体苹果酸脱氢酶基因并在大肠杆菌内表达,同时对表达的重组蛋白进行初步的功能分析,为进一步的研究和药物筛选打下基础。方法通过大规模测序从肝吸虫cDNA文库中确定肝吸虫线粒体苹果酸脱氢酶基因,采用PCR方法扩增出目的片段,与表达质粒pGEX-4T-1连接构建重组质粒,IPTG诱导表达;研究重组蛋白的理化性质及酶动力学特征,并寻找可能的抑制剂。结果成功表达出约64 kDa的重组蛋白,凝血酶切后为36 kDa蛋白,其酶活性为63.6U/mg。1.14 mM 4,4′-二甲氨基联苯甲醇处理30 min酶活性下降了60%;吡喹酮、灭滴灵和阿苯哒唑对酶活性无抑制作用;而5’-单磷酸腺苷对重组酶有竞争性抑制作用,其Ki为0.49。结论成功地表达了目的蛋白,为药物筛选提供了一个易于获得的候选蛋白分子。     

改良胫后肌移位术治疗腓总神经损伤后足下垂及内翻畸形

目的 探讨改良胫后肌移位术治疗腓总神经损伤所致足下垂及内翻畸形的早期疗效.方法 采用回顾性病例系列研究分析2017年12月至2019年10月北京积水潭医院收治的6例腓总神经麻痹性足下垂及内翻患者的临床资料,其中男4例,女2例;年龄33～48岁[(39.5 ±6.0)岁].左侧4例,右侧2例.患者均行胫后肌移位术,通过异...     

A Vaccine Based on the A/ASIA/G-VII Lineage of Foot-and-Mouth Disease Virus Offers Low Levels of Protection against Circulating Viruses from the A/ASIA/Iran-05 lineage

The recent emergence and circulation of the A/ASIA/G-VII (A/G-VII) lineage of foot-and-mouth disease virus (FMDV) in the Middle East has resulted in the development of homologous vaccines to ensure susceptible animals are sufficiently protected against clinical disease. However, a second serotype A lineage called A/ASIA/Iran-05 (A/IRN/05) continues to circulate in the region and it is therefore imperative to ensure vaccine strains used will protect against both lineages. In addition, for FMDV vaccine banks that usually hold a limited number of strains, it is necessary to include strains with a broad antigenic coverage. To assess the cross protective ability of an A/G-VII emergency vaccine (formulated at 43 (95% CI 8–230) PD₅₀/dose as determined during homologous challenge), we performed a heterologous potency test according to the European Pharmacopoeia design using a field isolate from the A/IRN/05 lineage as the challenge virus. The estimated heterologous potency in this study was 2.0 (95% CI 0.4–6.0) PD₅₀/dose, which is below the minimum potency recommended by the World Organisation for Animal Health (OIE). Furthermore, the cross-reactive antibody titres against the heterologous challenge virus were poor (≤log₁₀ 0.9), even in those cattle that had received the full dose of vaccine. The geometric mean r₁-value was 0.2 (95% CI 0.03–0.8), similar to the potency ratio of 0.04 (95% CI 0.004–0.3). Vaccination decreased viraemia and virus excretion compared to the unvaccinated controls. Our results indicate that this A/G-VII vaccine does not provide sufficient protection against viruses belonging to the A/IRN/05 lineage and therefore the A/G-VII vaccine strain cannot replace the A/IRN/05 vaccine strain but could be considered an additional strain for use in vaccines and antigen banks.     

Ovarian Sertoli-Leydig cell tumor with heterologous gastrointestinal epithelium as a source of alpha-fetoprotein: a case report

Ovarian Sertoli-Leydig cell tumors (SLCT) are rare sex cord stromal neoplasms. To date there have been approximately 25 case reports of ovarian SLCT expressing alpha-fetoprotein (AFP). In such cases, AFP was immunohistochemically detected in the Sertoli cells, Leydig cells, or hepatocytes. This case report confirms heterologous gastrointestinal epithelium expression of AFP. A 20-year-old woman presented with complaints of abdominal enlargement and irregular menstrual cycles over one year. A right ovarian tumor was detected and the patient's serum AFP was elevated. A right salpingo-oophorectomy was performed. On microscopic examination, the tumor was composed of a fibrosarcoma-like area and a poorly differentiated SLCT area with heterologous gastrointestinal epithelium. Immunohistochemical analysis detected AFP in the gastrointestinal epithelium only. Postoperatively, serum AFP levels fell to normal. A recurrent tumor was discovered in the omentum after adjuvant chemotherapy, but serum AFP remained normal. A second laparotomy was performed and the recurrent tumor showed only fibrosarcoma-like features. The patient received second line chemotherapy and is currently in remission. This is the first case of AFP production by heterologous gastrointestinal epithelium in SLCT.     

Phyllodes tumor with a benign heterologous osseous component: a diagnostic challenge

Phyllodes tumors (PTs) are rare fibroepithelial neoplasms of the breast and constitute 0.3–1% of all primary breast tumors. They should be characterized in to a benign, borderline or malignant category based on a combination of histological features. PTs can show heterologous components, typically sarcomatous, including osteosarcomatous and chondrosarcomatous. Benign heterologous components are exceedingly rare with only one prior reported case in the English literature. This case emphasizes how difficult establishing a correct diagnosis in PTs with heterologous components can be, especially when the tumor consists mainly of a benign heterologous component. We report the case of a 65 year old woman with a recurrent breast tumor initially misdiagnosed as benign osseous metaplasia. The tumor re‐occurred as a malignant PT dominated by benign osseous and chondroid metaplasia. Multiple metastases consisting of primarily mature bone and cartilage were seen in the lungs. On microscopic revision and considering the clinical course the primary breast tumor was re‐classified as a borderline PT.     

Heterologous COVID-19 Vaccination in Spain: A Case Study of Individual Autonomy in the Real World

In Spain, 1.5 million essential < 60-year-old workers were vaccinated with a first AstraZeneca vaccine dose. After assessing the cases of thrombosis with thrombocytopenia associated to this vaccine, the European Medicines Agency (EMA) supported the administration of 2 doses of the AstraZeneca vaccine with no age restrictions. Nevertheless, Spain decided not to administer the second dose of this vaccine to < 60-year-olds. The government sponsored a clinical trial (CombiVacS) to assess the immunogenicity response to a Pfizer/BioNTech vaccine dose in adults primed with the AstraZeneca vaccine. The positive results backed the Public Health Commission and the Spanish Ministry of Health to offer the Pfizer/BioNTech vaccine as the booster. Nevertheless, regional public health authorities—responsible for administering vaccines—believed that, following the EMA’s decision, an AstraZeneca booster dose should be given. The public confrontation of these 2 positions forced the Spanish Health Ministry to request the signature of an informed consent form to those individuals willing to receive the AstraZeneca vaccine booster and rejecting the Pfizer/BioNTech vaccine dose. Eventually, it was decided that these essential workers could choose the vaccine but signing an informed consent form. All relevant information was posted on the Ministry of Health and regional health authorities’ websites and provided to potential vaccine recipients at vaccination sites. Most individuals (≥ 75%) chose the AstraZeneca vaccine: perhaps because they likely trusted the EMA more than the CombiVacS results. This unprecedented and massive exercise of individual autonomy about the choice of COVID-19 vaccines from 2 different platforms has shown that adequately informed persons can autonomously weigh their options, regardless of government decisions. Exercising individual autonomy may contribute to the success of future COVID-19 booster vaccination campaigns.