Isolation and characterization of new human carrier peptides from two important vaccine immunogens

In the preparation of glycoconjugate vaccines in clinical practice, two highly immunogenic carrier proteins, CRM₁₉₇ and tetanus toxoid (TT), are predominantly conjugated with the capsular polysaccharides (CPSs) of bacterial pathogens. In addition, TT has long been used as an effective vaccine to prevent tetanus. While these carrier proteins play an important role in immunogenicity and vaccine design alike, their defined human major histocompatibility complex class II (MHCII) T cell epitopes are inadequately characterized. In this current work, we use mass spectrometry to identify the peptides from these carrier proteins that are naturally processed and presented by human B cells via MHCII pathway. The MHCII-presented peptides are screened for their T cell stimulation using primary CD4+ T cells from four healthy adult donors. These combined methods reveal a subset of eleven CD4+ T cell epitopes that proliferate and stimulate human T cells with diverse MHCII allelic repertoire. Six of these peptides stand out as potential immunodominant epitopes by responding in three or more donors. Additionally, we provide evidence of these natural epitopes eliciting more significant T cell responses in donors than previously published TT peptides selected from T cell epitope screening. This study serves toward understanding carrier protein immune responses and thus enables the use of these peptides in developing novel knowledge-based vaccines to combat persisting problems in glycoconjugate vaccine design.     

Mildly decreased preoperative bilirubin levels are associated with infections after shoulder and knee arthroplasty

Increasing numbers of arthroplasties are also accompanied by postoperative infections. The main purpose was to evaluate preoperative serum bilirubin levels between patients with and without infections after shoulder and knee arthroplasties. For this retrospective case-control single-center study, a total of 108 patients were extracted from a prospectively collected database. Eighteen patients with infections after shoulder (n = 8) and knee (n = 10) arthroplasty were matched by age, gender, and implant type in a 1:5-scenario to 90 patients (40 shoulders and 50 knees) without postoperative infection. Demographic data, preoperative blood parameters, and postoperative infection-related outcomes were evaluated. Total bilirubin was the only preoperative parameter significantly different between the infection (8.21 ± 3.25 μmol/L or 0.48 ± 0.19 mg/dL) and noninfection (10.78 ± 4.62 μmol/L or 0.63 ± 0.27 mg/dL; P = .014) group, while C-reactive protein and other liver parameters were similar between the groups. Significantly more controls (92.1%) had preoperative bilirubin levels above 8.72 μmol/L or 0.51 mg/dL than cases (7.9%; P = .007). The 5-year infection survival-rate was 65.6% for patients with preoperative bilirubin levels < 8.72 μmol/L or < 0.51 mg/dL and 91.2% with ≥ 8.72 μmol/L or ≥ 0.51 mg/dL. Mildly decreased preoperative bilirubin levels with a cutoff at 8.72 μmol/L or 0.51 mg/dL were significantly associated to patients with infections after shoulder and knee arthroplasty. There were no differences in other blood parameters or comorbidities between patients with infections and their matched-controls.     

地黄饮子加减方对血管性痴呆模型大鼠学习记忆能力及海马CA1区神经元损伤的影响

目的:观察地黄饮子加减方对血管性痴呆模型大鼠学习记忆能力及海马CA1区神经元的影响。方法:将84只SD雄性大鼠,按随机原则选出12只大鼠作为假手术组,其余72只大鼠采用两血管阻断法制备血管性痴呆模型,筛选60只模型大鼠,每组12只,随机分为模型组,尼莫地平组(0. 011 g·kg~(-1)),地黄饮子加减方高、中、低(4. 54,2. 27,1. 14 g·kg~(-1))剂量组。连续灌胃30 d后,Morris水迷宫检测大鼠学习记忆能力,苏木素-伊红(HE)观察海马CA1区神经元形态结构改变,透射电镜观察海马CA1区神经元超微结构变化,原位细胞凋亡检测法(TUNEL)检测海马CA1区细胞凋亡水平,免疫组化(IHC)检测海马CA1区组织磷脂酰肌醇3-激酶(PI3K),蛋白激酶B(Akt),半胱氨酸蛋白酶-3(Caspase-3)表达水平。结果:与假手术组比较,模型组大鼠逃避潜伏期显著延长,穿越原平台次数显著减少(P 0. 01),海马CA1区神经元形态均有不同程度地损伤,凋亡率显著增加(P 0. 01),PI3K,Akt的积分吸光度和平均积分吸光度明显降低(P 0. 01),Caspase-3的积分吸光度和平均积分吸光度显著增高(P 0. 01);与模型组比较,各给药组大鼠逃避潜伏期缩短(P 0. 05,P 0. 01),穿越原平台次数增加(P 0. 05,P 0. 01),PI3K,Akt的积分吸光度和平均积分吸光度值显著增高(P 0. 01),Caspase-3的积分光密度和平均积分吸光度不同程度降低(P 0. 05,P 0. 01)。结论:地黄饮子加减方可改善血管性痴呆模型大鼠学习记忆能力和海马CA1区神经元损伤,潜在机制可能与PI3K/Akt信号转导途径的激活,抑制大鼠海马CA1区神经细胞的凋亡有关。     

Basic fibroblast growth factor promotes doxorubicin resistance in chondrosarcoma cells by affecting XRCC5 expression

Chondrosarcoma is the second most common form of bone cancer and is characterized by its ability to produce an extracellular matrix of the cartilage. High-grade chondrosarcoma is highly aggressive and can metastasize to other parts of the body. Chondrosarcoma is resistant to both conventional chemotherapy and radiotherapy; hence, the current main treatment is still surgical resection. Doxorubicin (Dox) has been shown to significantly improve patient survival compared with untreated chondrosarcoma. However, for patients with metastasis, surgical resection alone can hardly treat them. In addition, drug resistance is one of the leading causes of death in patients with chondrosarcoma. Secreted proteins can mediate cell-cell interactions in the cancer microenvironment, which may be associated with the development of drug resistance. In the present study, chondrosarcoma cells were treated with Dox, the conditioned medium was then collected and changes in secreted proteins were analyzed using the antibody array. Results showed that the Dox-treated group had the highest secretion of basic fibroblast growth factor (bFGF), indicating the effect of bFGF on Dox sensitivity in chondrosarcoma. Furthermore, lentiviral-mediated knockdown and treatment of exogenous recombinant protein were employed to further investigate the effect of bFGF on Dox resistance. Results demonstrated that bFGF can promote the expression of X-ray repair cross-complementing protein 5 (XRCC5), leading to Dox resistance. Secreted bFGF is likely to be detected in serum, in addition to being a biomarker for predicting Dox resistance, the combination of Dox and bFGF/XRCC5 blockers may be a new therapeutic strategy to improve the efficacy of Dox in future.     

清热化瘀汤对急性脑出血患者血清hs-CRP、血浆S100β蛋白和NSE的影响

目的:探究清热化瘀汤联合依达拉奉对急性脑出血患者血清超敏C反应蛋白(hs-CRP)、血浆S100β蛋白和神经元特异性烯醇化酶(NSE)的影响。方法:选择2017年5月—2019年5月在我院神经内科就诊符合纳入标准的80例急性脑出血患者,随机分为联合组(40例)和依达拉奉组(40例),两组均给予基础治疗和依达拉奉静脉滴注治疗,联合组则在此基础上加用清热化瘀汤。观察并比较两组的临床疗效、神经功能缺损程度评分(NIHSS)、格拉斯哥昏迷评分(GCS)、hs-CRP、S100β蛋白和NSE水平及脑血肿量。结果:联合组的总有效率为95%(38/40),显著高于依达拉奉组的总有效率75%(30/40)(P<0.05)。治疗后,两组NIHSS评分降低,GCS评分升高,且联合组NIHSS评分明显低于依达拉奉组(P<0.05),GCS评分高于依达拉奉组(P<0.05)。治疗后,两组hs-CRP、S100β蛋白和NSE水平及均脑血肿量均低于治疗前,且联合组hs-CRP、S100β蛋白和NSE水平及脑血肿量明显低于依达拉奉组(P<0.05)。结论:清热化瘀汤联合依达拉奉对急性脑出血患者具有良好的疗效,可显著改善其神经缺损,降低hs-CRP、S100β蛋白和NSE水平及脑血肿量。     

基于蛋白质组学分析色胺酮抑制小鼠乳腺癌的作用机制

目的:采用非标记定量(Label-free)蛋白质组学技术研究色胺酮抗小鼠体内乳腺癌的作用机制。方法:采用超高效液相色谱-质谱联用技术检测色胺酮抗小鼠乳腺癌的表达蛋白,选择Ionoptics nano UPLC C18色谱柱(0.075 mm×250 mm,1.6μm),流动相0.1%甲酸水溶液-0.1%甲酸乙腈溶液梯度洗脱,正离子模式,扫描范围m/z 100～1 700,使用MaxQuant 1.6.5.0进行数据库检索。采用Label-free高分辨质谱的蛋白质组学技术筛选4T1乳腺癌小鼠模型组与色胺酮(100 mg·kg~(-1))口服给药组之间的差异表达蛋白,进行色胺酮抗乳腺癌的蛋白质组学研究。结果:共鉴定出3 997个蛋白质,其中有2 911个蛋白可定量。模型组与色胺酮组共750个差异表达蛋白,其中286个蛋白上调,464个蛋白下调。基因本体分析表明,这些差异表达蛋白主要参与增殖、细胞迁移、凋亡、免疫、血管生成和炎症调节等生物学过程。京都基因与基因组百科全书通路分析进一步表明,这些蛋白主要集中于T细胞受体,B细胞受体,Toll样受体,核转录因子-κB(NF-κB),Ras蛋白,白细胞介素-17,肿瘤坏死因子,磷脂酰肌醇3-激酶/蛋白激酶B(PI3K-Akt)和丝裂原活化蛋白激酶(MAPK)等信号通路。结论:与色胺酮抗4T1乳腺癌作用密切相关的差异表达蛋白包括上调蛋白白细胞分化抗原14(CD14),前列腺素G/H合酶2(PTGS2),泛素蛋白连接酶E3和下调蛋白CD44,70 kDa热休克蛋白1A(HSPA1A),巨噬细胞移动抑制因子(MIF),NF-κB,核糖体蛋白S6激酶α-4(RPS6KA4)和高迁移率族蛋白B1(HMGB1),提示色胺酮主要通过调节肿瘤炎症微环境来达到抑制小鼠乳腺癌的作用。     

Association between de novo lipogenesis susceptibility genes and coronary artery disease

Background and aimsCoronary artery disease (CAD) is the principal cause of death in individuals with non-alcoholic fatty liver disease (NAFLD). The aim of this study was to use genetic epidemiology to study the association between de novo lipogenesis (DNL), one of the major pathways leading to NAFLD, and CAD risk.Methods and resultsDNL susceptibility genes were used as instruments and selected using three approaches: 1) genes that are associated with both high serum triglycerides and low sex hormone-binding globulin, both downstream consequences of DNL (unbiased approach), 2) genes that have a known role in DNL (biased approach), and 3) genes that have been associated with serum fatty acids, used as a proxy of DNL. Gene-CAD effect estimates were retrieved from the meta-analysis of CARDIoGRAM and the UK Biobank (～76014 cases and ～264785 controls). Effect estimates were clustered using a fixed-effects meta-analysis. Twenty-two DNL susceptibility genes were identified by the unbiased approach, nine genes by the biased approach and seven genes were associated with plasma fatty acids. Clustering of genes selected in the unbiased and biased approach showed a statistically significant association with CAD (OR:1.016, 95%CI:1.012; 1.020 and OR:1.013, 95%CI:1.007; 1.020, respectively), while clustering of fatty acid genes did not (OR:1.004, 95%CI:0.996–1.011). Subsequent exclusion of potential influential outliers did reveal a statistically significant association (OR:1.009, 95%CI:1.000; 1.018).ConclusionsDNL susceptibility genes are associated with an increased risk of CAD. These findings suggest that DNL may be involved in the pathogenesis of CAD and favor further development of strategies that target NAFLD through DNL.     

Clinicopathological analysis of immunohistochemical expression of CD47 and SIRPα in adult T-cell leukemia/lymphoma

The interaction of CD47 and signal-regulatory protein alpha (SIRPα) induces “don't eat me signal”, leading suppression of phagocytosis. This signal can affect the clinical course of malignant disease. Although CD47 and SIRPα expression are associated with clinicopathological features in several neoplasms, the investigation for adult T-cell leukemia/lymphoma (ATLL) has not been well-documented. This study aimed to declare the association between CD47 and SIRPα expression and clinicopathological features in ATLL. We performed immunostaining on 73 biopsy samples and found that CD47 is primarily expressed in tumor cells, while SIRPα is expressed in non-neoplastic stromal cells. CD47 positive cases showed significantly higher FoxP3 (P = .0232) and lower CCR4 (P = .0214). SIRPα positive cases presented significantly better overall survival than SIRPα negative cases (P = .0132). SIRPα positive cases showed significantly HLA class I (P = .0062), HLA class II (P = .0133), microenvironment PD-L1 (miPD-L1) (P = .0032), and FoxP3 (P = .0229) positivity. In univariate analysis, SIRPα expression was significantly related to prognosis (Hazard ratio [HR] 0.470; 95% confidence interval [CI] 0.253-0.870; P = .0167], although multivariate analysis did not show SIPRα as an independent prognostic factor. The expression of SIRPα on stromal cells reflects activated immune surveillance mechanism in tumor microenvironment and induce good prognosis in ATLL. More detailed studies for gene expression or genomic abnormalities will disclose clinical and biological significance of the CD47 and SIRPα in ATLL.