Comparing the efficiency of different Escherichia coli strains in producing recombinant capsid protein of porcine circovirus type 2

The present study was aimed at comparing different E. coli strains in expressing the capsid protein of Porcine Circovirus 2 (PCV2). Full length capsid protein could be expressed only in Rosetta-gami 2 (DE3) pLysS strain using pET32b (+) vector. This confirmed that only those strains which possess tRNAs for rare codons can express the full length capsid protein. Purification of full length capsid protein could not be achieved even after several attempts using native and denaturing conditions. Subsequently, an attempt was made for expression of N-terminal truncated capsid protein using the same expression system. Truncated capsid protein was successfully expressed, purified and characterized by western blotting. The truncated capsid protein was also shown to be efficacious in testing serum samples using an optimized indirect ELISA, wherein a diagnostic sensitivity of 88.89% and specificity of 90.82% was obtained as compared to commercially available GreenSpring® porcine circovirus (PCV2) ELISA test kit. Thus, the expressed truncated capsid protein appears to be a promising diagnostic agent for PCV2. The comparative analysis suggests that cluster of arginine residues at N-terminal of capsid protein not only affects its expression in some E. coli strains but also its purification by Ni-NTA chromatography, when expressed as a histidine tagged fusion protein.     

基于p38 MAPK信号通路探讨苍膝通痹胶囊对KOA大鼠关节软骨的保护作用

目的:观察苍膝通痹胶囊治疗膝骨关节炎(KOA)模型大鼠的疗效及相关作用机制。方法:将60只4周龄SPF级健康雄性SD大鼠,随机分为空白组,模型组,二甲基亚砜(DMSO)组,苍膝通痹胶囊组,SB203580组以及苍膝通痹胶囊联合SB203580组,每组10只。除正常组外,其余各组采用改良Hulth法建立KOA模型,造模成功后,苍膝通痹胶囊组每日给予0.25 g·kg~(-1)苍膝通痹胶囊溶液灌胃,SB203580组每日给予0.015 g·kg~(-1)的SB203580溶液灌胃,苍膝通痹胶囊联合SB203580组组每日给予含0.015 g·kg~(-1)SB203580及0.25 g·kg~(-1)苍膝通痹胶囊的混合溶液灌胃,DMSO组给予1%DMSO溶液灌胃,模型组和空白组给予生理盐水灌胃,用药干预4周后处死、取材。苏木素-伊红(HE)染色观察软骨组织形态学改变,酶联免疫吸附测定(ELISA)检测外周血上清液中白细胞介素-1β(IL-1β),肿瘤坏死因子-α(TNF-α)表达水平,实时荧光定量PCR(Real-tine PCR)及蛋白免疫印迹法(Western blot)检测软骨组织中p38 MAPK信号通路中相关因子p38,p-p38,基质金属蛋白酶-13(MMP-13),Ⅱ型胶原蛋白(CollagenⅡ)mRNA及蛋白的表达水平,免疫组化法检测p-p38的定位表达。结果:与正常组比较,模型组关节软骨中p38,p-p38,MMP-13表达水平显著上调(P0.01),CollagenⅡ表达水平显著下调(P0.01),血清IL-1β,TNF-α表达水平显著上调(P0.01);与模型组比较,苍膝通痹胶囊组,SB203580组以及苍膝通痹胶囊联合SB203580组关节软骨中p38,p-p38,MMP-13表达水平显著下调(P0.01),CollagenⅡ表达水平显著上调(P0.01),血清IL-1β,TNF-α表达水平显著下调(P0.01)。结论:苍膝通痹胶囊可有效保护KOA大鼠软骨组织,其机制可能与靶向阻断p38 MAPK信号通路有关。     

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.     

The key role of macrophage depolarization in the treatment of COPD with ergosterol both in vitro and in vivo

Macrophages are the most abundant immune cells in the lung, which play an important role in COPD. The anti-inflammatory and anti-oxidation of ergosterol are well documented. However, the effect of ergosterol on macrophage polarization has not been studied. The objective of this work was to investigate the effect of ergosterol on macrophage polarization in CSE-induced RAW264.7 cells and Sprague-Dawley (SD) rats COPD model. Our results demonstrate that CSE-induced macrophages tend to the M1 polarization via increasing ROS, IL-6 and TNF-α, as well as increasing MMP-9 to destroy the lung construction in both RAW264.7 cells and SD rats. However, treatment of RAW264.7 cells and SD rats with ergosterol inhibited CSE-induced inflammatory by decreasing ROS, IL-6 and TNF-α, and increasing IL-10 and TGF-β, shuffling the dynamic polarization of macrophages from M1 to M2 both in vitro and in vivo. Ergosterol also decreased the expression of M1 marker CD40, while increased that of M2 marker CD163. Moreover, ergosterol improved the lung characters in rats by decreasing MMP-9. Furthermore, ergosterol elevated HDAC3 activation and suppressed P300/CBP and PCAF activation as well as acetyl NF-κB/p65 and IKKβ, demonstrating that HDAC3 deacetylation was involved in the effect of ergosterol on macrophage polarization. These results also provide a proof in immunoregulation of ergosterol for therapeutic effects of cultured C. sinensis on COPD patients.     

A prognostic signature based on immune-related genes for cervical squamous cell carcinoma and endocervical adenocarcinoma

Cervical squamous cell carcinoma and endocervical adenocarcinoma (CESC) is the fourth commonest female malignancy worldwide. CESC progresses in immune-microenvironment mainly composed of infiltrating immune and stromal cells. Here, we performed an integrated analysis incorporating the expression profiles from the Cancer Genome Atlas (TCGA) database and scores of immune and stromal cells calculated by Estimation of Stromal and Immune cells in Malignant Tumours using Expression data (ESTIMATE) algorithm. A two-gene signature (CD1C and CD6 genes) was established to predict the prognosis of CESC. Based on this signature, patients were divided into the high- and low-risk groups, and this signature showed good prognostic performance according to the results of Kaplan-Meier analysis and receiver operating characteristic (ROC) analysis in train set and two validation sets. A nomogram was built for evaluating the clinical applicability of this signature. In addition, based on Tumor Immune Estimation Resource (TIMER) database, 2 hub genes showed negative correlations with tumor purity and positive correlations with infiltrating levels of immune filtrating cells. What’s more, we propose new treatment strategies for the two prognostic subtypes. Low- risk patients were found presenting with a higher level of immune checkpoint molecules and showing higher immunogenicity in immunophenoscore (IPS) analysis, which indicated a better response for immunotherapy. Meanwhile, estimated by Genomics of Drug Sensitivity in Cancer (GDSC) database, the high-risk patients showed sensitive responses to five chemotherapy drugs. Finally, 10 candidate small-molecule drugs for CESC were defined. In summary, the CD1C-CD6 signature can accurately predict the prognosis of CESC.     

Does perturbation in the mitochondrial protein folding pave the way for neurodegeneration diseases?

Mitochondria, which are cell compartments that are widely present in eukaryotic cells, have been shown to be involved in a variety of synthetic, metabolic, and signaling processes, thereby playing a vital role in cells. The mitochondrial unfolded protein response (mtUPR) is a response in which mitochondria reverse the signal to the nucleus and maintain mitochondrial protein homeostasis when unfolded and misfolded proteins continue to accumulate. Multiple neurodegeneration diseases, including Alzheimer's disease (AD), Parkinson’s disease (PD), and familial amyotrophic lateral sclerosis (fALS), are public health challenges. Every year, countless efforts are expended trying to clarify the pathogenesis and treatment of neurological disorders, which are associated with mitochondrial dysfunction to some extent. Numerous studies have shown that mtUPR is involved in and plays an important role in the pathogenesis of neurological disorders, but the exact mechanism of the disorders is still unclear. Further study of the process of mtUPR in neurological disorders can help us more accurately understand their pathogenesis in order to provide new therapeutic targets. In this paper, we briefly review mtUPR signaling in Caenorhabditis elegans (C. elegans) and mammals and summarize the role of mtUPR in neurodegeneration diseases, including AD, PD and fALS.