Nanoparticle‐Based Manipulation of Antigen‐Presenting Cells for Cancer Immunotherapy

Immunotherapeutic approaches for treating cancer overall have been receiving a considerable amount of interest due to the recent approval of several clinical formulations. Among the different modalities, anticancer vaccination acts by training the body to endogenously generate a response against tumor cells. However, despite the large amount of work that has gone into the development of such vaccines, the near absence of clinically approved formulations highlights the many challenges facing those working in the field. The generation of potent endogenous anticancer responses poses unique challenges due to the similarity between cancer cells and normal, healthy cells. As researchers continue to tackle the limited efficacy of vaccine formulations, fresh and novel approaches are being sought after to address many of the underlying problems. Here the application of nanoparticle technology towards the development of anticancer vaccines is discussed. Specifically, there is a focus on the benefits of using such strategies to manipulate antigen presenting cells (APCs), which are essential to the vaccination process, and how nanoparticle‐based platforms can be rationally engineered to elicit appropriate downstream immune responses.     

Direct visualization of colloidal gold-bound molecules and a cell-surface receptor by ultrahigh-resolution scanning electron microscopy

The structure of protein A-coated colloidal gold particles, and of macrophage cell-surface receptors conjugated with immunogold particles, was studied using an ultrahigh-resolution scanning electron microscope. Protein A, when conjugated with 15-nm gold, formed a coat completely surrounding the particle. Particles conjugated with both protein A and immunoglobulin G (IgG) were similar, but with additional protrusions formed by the IgG. IgG molecules directly bound to gold were resolved sometimes as complexes of three units, sometimes as more filamentous, V-shaped structures. On the cell surface of a macrophage reacted with a monoclonal antibody to Mac-1 antigen (the murine C3bi receptor) followed by protein A-gold, gold particles were seen to be linked via the IgG to the receptor, visualized as a round granule.     

New insights into the cellular makeup and progenitor potential of palatal connective tissues

The present study investigated the regenerative potential of connective tissues harvested from two palatal areas widely used as donor sites for muco‐gingival surgical approaches. Connective tissue grafts (CTGs) were obtained by de‐epithelialisation of a free gingival graft (deCTG) and by a split flap approach from a previous donor site (reCTG). Two types of mesenchymal stem cell (MSCs) were isolated and were named de‐epithelialised MSCs (deMSCs) and re‐entry MSCs (reMSCs). The cells were characterised and cellular functionality was investigated. CTGs were evaluated using immunohistochemical and ultrastructural approaches. No significant differences were observed regarding the frequency of colony‐forming unit‐ fibroblasts, migration potential, and population doubling time between the two cell lines (p > 0.05). Both cell lines showed positivity for CD105, CD73, CD90, and CD44 and negative expression for CD34/45, CD14, CD79a, and HLA‐DR. MSCs from both cell lines successfully differentiated into osteogenic, adipogenic, and chondrogenic lineages. Cells expressing antigens characteristic of CD34+ stromal cells (CD34+, αSMA?, CD31?) were traced in both CTGs. Ultrastructural analysis highlighted the presence of putative progenitors, namely fibroblasts,—in the pericapillary regions and in remote regions of the lamina propria‐ and pericytes—surrounding the capillaries. This study provides supplementary arguments for the use of CTG grafts in clinical practice due to the presence of putative progenitor cell. However, results were inconclusive regarding clinical decision‐making to determine optimal harvesting area. Prior harvesting in the donor area did not appear to alter the regenerative capabilities of the connective tissue.     

Rapid screening and identification of dominant B cell epitopes of HBV surface antigen by quantum dot-based fluorescence polarization assay

A method for quickly screening and identifying dominant B cell epitopes was developed using hepatitis B virus (HBV) surface antigen as a target. Eleven amino acid fragments from HBV surface antigen were synthesized by 9-fluorenylmethoxy carbonyl solid-phase peptide synthesis strategy, and then CdTe quantum dots were used to label the N-terminals of all peptides. After optimizing the factors for fluorescence polarization (FP) immunoassay, the antigenicities of synthetic peptides were determined by analyzing the recognition and combination of peptides and standard antibody samples. The results of FP assays confirmed that 10 of 11 synthetic peptides have distinct antigenicities. In order to screen dominant antigenic peptides, the FP assays were carried out to investigate the antibodies against the 10 synthetic peptides of HBV surface antigen respectively in 159 samples of anti-HBV surface antigen-positive antiserum. The results showed that 3 of the 10 antigenic peptides may be immunodominant because the antibodies against them existed more widely among the samples and their antibody titers were higher than those of other peptides. Using three dominant antigenic peptides, 293 serum samples were detected for HBV infection by FP assays; the results showed that the antibody-positive ratio was 51.9% and the sensitivity and specificity were 84.3% and 98.2%, respectively. In conclusion, a quantum dot-based FP assay is a very simple, rapid, and convenient method for determining immunodominant antigenic peptides and has great potential in applications such as epitope mapping, vaccine designing, or clinical disease diagnosis in the future.     

抗人红细胞表面抗原glycophorin A杂交瘤细胞株的建立

应用杂交瘤技术,用纯化人红细胞表面抗原glycophorin A“N”型免疫纯系BALB/c小鼠,用glycophorin A“M”型作为固相抗原,用EIA间接筛选出识别“M”、“N”血凝抗原以外的抗glycophorin A的抗体,进而利用Coombs原理,加入抗免疫球蛋白,筛选出非凝集型抗glycophorin A抗体,得到61株非凝集型抗glycophorin A杂交瘤,其中12株有限稀释法克隆4次后得到5株稳定分泌非凝集型抗体的杂交瘤并进行初步鉴定。单抗上清血凝效价可达1:20～50,腹水血凝效价为1:800～1:1 600。     

Hesperidin inhibits development of atopic dermatitis-like skin lesions in NC/Nga mice by suppressing Th17 activity

Hesperidin (previously called vitamin P) is a predominant flavanone present in citrus fruits, and is presumed to have a role in their beneficial effect for human health because it possesses various physiological activities. In this study, we investigated the anti-allergic and anti-inflammatory effects of hesperidin and α-glucopyranosyl (αG)-hesperidin, its derivative with enhanced water-solubility, in NC/Nga mice, a human-like mouse model of atopic dermatitis. NC/Nga mice were fed a 0.1% αG-hesperidin or hesperidin diet for 8 weeks. αG-hesperidin and hesperidin feeding effectively inhibited skin lesions and immunoglobulin E (IgE) elevation. At the end of the 8-week-experimental period, the production of inflammatory cytokine interleukin (IL)-17 and interferon-gamma (IFN-γ) from splenocytes was lower in the αG-hesperidin/hesperidin-fed group than in the control group. Changes in mRNA expression in splenocytes are also examined using DNA microarray and real-time RT-PCR. It was revealed that cytotoxic T-lymphocyte antigen 4 (CTLA4), a regulatory T-cell (Treg) marker, was markedly upregulated in splenocytes, particularly by αG-hesperidin feeding. These results suggest that αG-hesperidin attenuated exacerbation of AD-like symptoms, decreased systemic immune hyper-responsiveness in part through the reduction of IgE, IL-17 and IFN-γ, and also modulated Th17/Treg balance in NC/Nga mice. Therefore, αG-hesperidin may be useful in the management of Th17-mediated allergic disorders.     

糖类抗原19-9在膀胱癌患者尿液中异常表达

通过检测膀胱癌患者尿液中糖类抗原 1 9- 9(CA1 9- 9)的含量 ,分析并评估其对诊断膀胱癌的临床价值。用全自动化学荧光系统检测膀胱癌患者 (3 0例 ) ,泌尿系统常见良性疾病 (5 3例 )、恶性疾病 (2 2例 )和其它系统恶性肿瘤 (3 5例 )患者以及 3 0例为既往无各系统恶性肿瘤和泌尿系统病史的志愿者 (对照组 )尿液中CA1 9- 9含量。结果显示 ,膀胱癌组CA1 9- 9含量水平为 1 5 9.0± 1 2 8.0U/mL。对照组的尿CA1 9- 9含量水平为 1 2 .4± 8.4U/mL。以对照组均值± 1 .96SD为临界点 ,即大于 2 8.9U/mL为阳性。膀胱移行细胞癌诊断灵敏度 86.7%、特异性 68.2 %。膀胱癌组与对照组的尿CA1 9- 9含量差异有显著统计意义 (P <0 .0 0 1 ) ,与其它各组差异也有显著统计意义 (P <0 .0 0 1 )。良性泌尿系统疾病组尿CA1 9- 9含量水平为 5 3 .9± 77.9U/mL ,明显高于对照组 (P =0 .0 0 1 ) ,但与泌尿系统其它恶性肿瘤组和其它系统恶性肿瘤组之间差别无显著意义     

Influence of Long-Distance Bicycle Riding on Serum/Urinary Biomarkers of Prostate Cancer

Herein, we present a study focused on the determination of the influence of long-distance (53 km) bicycle riding on levels of chosen biochemical urinary and serum prostate cancer (PCa) biomarkers total prostate-specific antigen (tPSA), free PSA (fPSA) and sarcosine. Fourteen healthy participants with no evidence of prostate diseases, in the age range from 49–57 years with a median of 52 years, underwent physical exercise (mean race time of 150 ± 20 min, elevation increase of 472 m) and pre- and post-ride blood/urine sampling. It was found that bicycle riding resulted in elevated serum uric acid (p = 0.001, median 271.76 vs. 308.44 µmol/L pre- and post-ride, respectively), lactate (p = 0.01, median 2.98 vs. 4.8 mmol/L) and C-reactive protein (p = 0.01, 0.0–0.01 mg/L). It is noteworthy that our work supports the studies demonstrating an increased PSA after mechanical manipulation of the prostate. The subjects exhibited either significantly higher post-ride tPSA (p = 0.002, median 0.69 vs. 1.1 ng/mL pre- and post-ride, respectively) and fPSA (p = 0.028, median 0.25 vs. 0.35 ng/mL). Contrary to that, sarcosine levels were not significantly affected by physical exercise (p = 0.20, median 1.64 vs. 1.92 µmol/mL for serum sarcosine, and p = 0.15, median 0.02 µmol/mmol of creatinine vs. 0.01 µmol/mmol of creatinine for urinary sarcosine). Taken together, our pilot study provides the first evidence that the potential biomarker of PCa—sarcosine does not have a drawback by means of a bicycle riding-induced false positivity, as was shown in the case of PSA.     

The Influence of PSCA Gene Variation on Its Expression and Gastric Adenocarcinoma Susceptibility in the Northwest Chinese Population

Gastric adenocarcinoma (GAC) imposes a considerable health burden around the world. Gene variation in prostate stem cell antigen gene (PSCA) has been identified to be associated with GAC risk, while the results showed regional variation. To explore the influence of PSCA gene variation on its expression and GAC risk in the Northwest Chinese population, four single nucleotide polymorphisms (SNPs) of PSCA were genotyped in 476 GAC cases and 481 controls using MassARRAY system. Two SNPs of rs2294008 (C>T) and rs2976392 (G>A) were identified to be associated with GAC risk. rs2294008, rs2976392 and rs10216533 made up two statistically significant haplotypes (Hap-CGG and Hap-TAG). Additionally, PSCA expression was analyzed by quantitative real time PCR, immunohistochemistry and tissue microarray. The results showed that PSCA expression was decreased in GAC tissues compared with adjacent normal tissues. For normal tissues, PSCA expression was higher with Hap-TA than that with Hap-CG. For GAC tissues, the differentiation degree of Hap-TA was higher than that of Hap-CG. The expression distribution of PSCA in multiple human organs showed disparity. These results suggest that PSCA gene variation has a potential effect on its expression and GAC risk in the Northwest Chinese population.     

AFM与SNOM表征抗原抗体分子的分布与特异性作用

分析免疫系统中抗原抗体分子的分布及其特异性作用对研究生命体生理机能、疾病的诊断与治疗等方面有着重要的作用。随着免疫学研究从细胞水平向分子水平的深入,高分辨和高灵敏度仪器得到更重要和广泛地应用。简单介绍了原子力显微镜(AFM)和扫描近场光学显微镜(SNOM)的特点,对近几年AFM和SNOM原位探测细胞表面分子的研究进行了分析总结,同时着重阐述了AFM和SNOM在抗原抗体分子之间特异性作用、抗体分子结构以及细胞表面抗原抗体的分布等方面的应用。