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Hepatocellular carcinoma (HCC) is one of the most lethal cancers worldwide due to a high rate of tumour metastasis and disease recurrence. In physiological conditions, tetraspanins interact with specific partner proteins in tetraspanin‐enriched microdomains and regulate their subcellular localization and function. However, the function of Tspan5 in pathological processes, particularly in cancer biology and its clinical significance, are still unclear. Here, we describe that a high expression of Tspan5 is significantly associated with some clinicopathological features including invasive length, vascular invasion, clinical stage and poor overall survival of HCC patients. Alterations of Tspan5 expression by lentivirus transductions in HCC cells demonstrated that Tspan5 promotes wound healing and cell migration in vitro and tumour metastasis of HCC cells in vivo. Mechanistic studies revealed that Tspan5 promoted cell migration and tumour metastasis by increasing the enzymatic maturation of ADAM10 and activating Notch signalling via the increase of the cleavage of the Notch1 receptor catalysed by the γ‐secretase complex. Activation of Notch signalling by Tspan5 was shown further to enhance the epithelial–mesenchymal transition (EMT) and actin skeleton rearrangement of tumour cells. In clinical HCC samples, Tspan5 expression is strongly correlated with many key molecules acting in Notch signalling and EMT, highlighting the role of Tspan5 in the regulation of Notch signalling, EMT and tumour metastasis of HCC. Our findings provide new insights into the mechanism of tumour metastasis and disease progression of HCC and may facilitate the development of novel clinical intervention strategies against HCC., We demonstrated that Tspan5 promotes the enzymatic maturation of ADAM10 and activates Notch signalling. The γ‐secretase complex catalyses the cleavage of Notch1 for the release of NICD, which is then translocated to the nucleus where it activates Notch target gene transcription. By activating Notch signalling, Tspan5 promoted epithelial–mesenchymal transition, actin skeleton rearrangement, tumour migration and metastasis of HCC, resulting in poor patient survival.

Aim: Development of a routine screening technique for Chlamydia trachomatis infection. The proposed approach involves the CRISPR RNA (crRNA). In the presence of the target sequence, the RNase activity of the Cas13a protein is activated, and it cleaves RNA fluorescent probe so that fluorescence will be emitted. Results: The sensitivity of the detection based on CRISPR-Cas13a was 10 fM. The results obtained by CRISPR-Cas13a and quantitative polymerase chain reaction were closely correlated: χ2 = 81.798 (p < 0.001). Conclusion: The method can be carried out at room temperature and yields results within 2 h. The developed technique does not require expensive instruments and, thus, can meet the needs of community hospitals and other institutions for screening.

Establishing personalized medication plans for patients to maximize therapeutic efficacy and minimize the toxicity of vancomycin (VAN) requires rapid, simple, and accurate monitoring of VAN concentration in body fluid. In this study, we have developed a simple and rapid analytical method by integrating Eu (III) chelate nanoparticles (CN-EUs) and lateral flow immunoassay (LFIA) to achieve the real-time monitoring of VAN concentration in serum within 15 min. This approach was performed on nitrocellulose (NC) membrane assembled LFIA strips via indirect competitive immunoassay and exhibited a wide linear range of detection (0.1–80 μg*ml−1) with a low limit of detection (69.2 ng*ml−1). The coefficients of variation (CV) of the intra- and inter-assay in the detection of VAN were 7.12–8.53% and 8.46–11.82%, respectively. The dilution test and specificity indicated this method had a stability that was not affected by the serum matrix and some other antibiotics. Furthermore, the applicability of the proposed method was assessed by comparing the determined results with those measured by LC-MS/MS, showing a satisfactory correlation (R2 = 0.9713). The proposed CN-EUs-based LFIA manifested promising analytical performance, which showed potential value in the real-time monitoring of VAN and could help optimize the clinical use of more antibiotics.

Neutrophil gelatinase-associated lipocalin (NGAL) is a promising biomarker for diagnosing acute kidney injury (AKI). Currently, there are few assays for determining NGAL and they are complex, time-consuming or expensive. We aimed to establish an efficient immunoassay to measure NGAL in human urine simply and rapidly. A novel immunoassay for NGAL determination was established by combining a dissociation-enhanced-free time-resolved fluoroimmunoassay (TRFIA) and immunomagnetic separation. Based on a “sandwich”-type immunoassay format, analytes in samples were captured by a pair of monoclonal antibodies (mAb) in which one mAb was coated in magnetic beads and the other mAb was labeled with europium(III) chelate microparticles (CM-EUs) as “fluorescent reporters”. NGAL concentrations were determined in a linear range (10–1500 ng mL−1) with a limit of detection of 0.32 ng mL−1. The reproducibility, recovery, and specificity of our TRFIA were acceptable. Our method was compared with that of a chemiluminescence immunoassay (CMIA) using 115 urine samples, and the results showed good correlation (R2 = 0.8677). We expect our novel method to be useful for the early diagnosis of AKI.

Semiconductor quantum dots (QDs) have attractive optical characteristics such as broad excitation spectra, narrow emission spectra, long fluorescence lifetime and negligible optical bleaching. Due to these characteristics, QDs have many important roles in fluorescence imaging and labeling. In recent years, QDs have been widely used as biolabels and biosensors in tumor research. The useful photophysical and chemical properties of QDs make them strong candidates for use in early tumor diagnosis, prognosis, and monitoring. Besides, QDs have also been applied in tumor drug delivery systems and photodynamic therapy, so they are of considerable significance in tumor research. In this review, we introduce the optical properties of QDs and summarize their various applications in tumor research, especially in tumor imaging, tumor serum diagnosis, tumor drug delivery, and photodynamic therapy. Finally, conclusions are made by providing some critical challenges and prospects of QDs in tumor research.

Development of sensitive homogeneous assays is a high-priority research target for clinical diagnostics. Quantum dots (QDs) present favorable photophysical properties, which implies their potential as an exceptional dye in fluorescence detection. QDs-based biosensors have been described in the literature; however, few of them have truly progressed to widespread clinical usage. In this work, a chemiluminescent homogeneous detecting biosensor is fabricated using QDs-doped polystyrene nanospheres to sensitively detect biomarkers in low-volume serum samples. Phthalocyanine-dyed and QDs-encapsulated carboxylate-functionalized polystyrene nanospheres with surface carboxyl groups (PPs and QPs, respectively) were fabricated and served as triggers and fluorescent probes, respectively, in this biosensing system. In this sandwich-format immunoassay, the PPs produced singlet oxygen once sensitized by 680 nm diode lasers, and the QPs, conjugated with antibodies, and then reacted with the singlet oxygen in the presence of specific antigens and emitted anti-Stokes fluorescence with wavelengths around 605 nm, as a result of fluorescence resonance energy transfer (FRET) within the QPs. We demonstrated the determination of carcinoembryonic antigen as a model protein target in 25 μL of serum samples with an unprecedented detection limit of 2.56 × 10-13 M (46 pg/mL) using this biosensor. Furthermore, excellent correlations ( R2 = 0.99718, n = 107) were obtained between utilizing this biosensor and commercialized chemiluminescence immunoassay kits in clinical serum detection. These results demonstrate that our flexible and reliable biosensor is suitable for direct integration into clinical diagnostics, and it is expected to be a promising diagnostic tool for early detection and screening tests as well as prognosis evaluation for patients.

Objective: To understand the role of WFDC2 in metastasis of ovarian cancer. Methods: By knockdown or overexpression of WFDC2, we demonstrated the role of WFDC2 in epithelial-mesenchymal transition (EMT). Results: We demonstrated that stable knockdown of WFDC2 suppressed EMT along with the upregulation of E-cadherin and the downregulation of Vimentin. In addition, WFDC2 knockdown decreases matrix metalloproteinase-2 (MMP-2) expression in in vitro cell model and in in vivo nude mice xenografts. The correlation of WFDC2 and MMP-2 expression in the clinical sample confirmed that WFDC2 was tightly correlated with the development of tumor. More importantly, the EMT phenotype and cell invasion induced by WFDC2 overexpressing can be reversed by the siMMP-2 and P13K/AKT signaling inhibitor. Conclusion: WFDC2 contributed to ovarian cancer metastasis and EMT as a positive regulator by activating AKT signaling pathway and inducing MMP-2 expression.

The morbidity and mortality associated with acute kidney injury (AKI) remain obstinately high. Early diagnosis is urgently required and should be pursued in at-risk populations. Recently, a newly validated biomarker, matrix metalloproteinase-7 (MMP-7), was reported as a novel indicator for early AKI prediction and a noninvasive surrogate biomarker of kidney function. Monitoring urinary MMP-7 (uMMP-7) levels fills the gaps in early diagnosis of AKI at early onset. However, the lack of available reagents for its rapid detection limits its use. Herein, we established an ultrasensitive and rapid immunomagnetic microparticles-based time-resolved fluoroimmunoassay to measure urinary MMP-7 in AKI patients. The assay time is 30 min. The calibration curve showed high linear correlation (r = 0.9998) with a linearity of detection of 0.063–150 ng mL−1 and lower limit of detection of 0.039 ng mL−1. The coefficient variation of the intra- and inter-assay lower than 5.17%, and the analytical recovery was 99.06%–105.60%. Testing of clinical samples using the proposed assay and a DUOSET@ ELISA kit showed good correlations in the comparison of uMMP-7 levels (r = 0.9541) and uMMP-7/uCreatinine (r = 0.9595). The proposed assay has satisfactory analytical performance and may serve as a promising tool for early diagnosis of AKI.

Despite burgeoning development of nanoplatform made in the past few years, it remains a challenge to produce drug nanocarrier that enables requested on/off drug release. Thus, this study aimed to develop an ideal near-infrared light-triggered smart nanocarrier for targeted imaging-guided treatment of cancer that tactfully integrated photothermal therapy with chemotherapy to accurately control drug release time and dosage. Methods: This delivery system was composed of Ag2S QD coating with dendritic mesoporous silica (DMSN), which acted as nanocarrier of doxorubicin localized inside pores. To provide the nanocarrier with controlled release capability, a polypeptide-engineered that structure was reversible to photothermal effect of Ag2S QD, was covalently grafted to the external surface of drug-loaded DMSN. Results: This nanocarrier with the size of 40~60 nm had satisfactory biocompatibility and photothermal conversion efficiency up to 28.35%. Due to acidity-triggered charge reversal of polypeptide, which significantly extended circulation time and improved targeting ability, fluorescence and photoacoustic signals were still obvious at tumor site post-24 h by tail vein injection and chemo-photothermal synergistic therapy obviously enhanced antitumor efficacy. Mild PTT with multiple short-term exposures not only reduced the side effect of overdose drug but also avoided skin damage caused by long-term irradiation. Conclusion: By adjusting irradiation time and on/off cycle, multiple small amount local drug release reduced the side effect of overdose drug and skin damage. This novel approach provided an ideal near-infrared light-triggered nanocarrier with accurate control of area, time, and especially dosage.

Currently, quality control of glycoprotein in the human rabies vaccine is based on enzyme-linked immunosorbent assay (ELISA). However, ELISA does not match the needs of a modernised quality control system. For a long time, human rabies virus vaccine manufacturers have been devoted to seeking a detection platform that is sensitive, accurate, automatic, and feasible for practical applications. Therefore, our team invested major efforts into establishing a fully automated micromagnetic particle (MMP)-based chemiluminescence immunoassay (CLIA) platform. For vaccine quality control, MMP-coupled rabies virus glycoprotein monoclonal antibodies (S037) were used to capture the rabies virus. Another rabies virus glycoprotein antibody (S053) labelled with acridinium ester was added as a signal tracer. After pretreating the vaccine sample, the entire analysis was performed using a fully automated machine, which had a limited detection time (only 30 min) and eliminated manual error. Multiple experiments have identified the optimal conditions allowing valid and reliable assessment of vaccine potency. The CLIA platform has exhibited merits in terms of speed, robustness, high sensitivity (with a minimum detection value of 0.45 mIU/mL), considerable accuracy, and a wide linear range of detection (9.4-1200 mIU/mL). Furthermore, the results showed that the CLIA platform is consistent with the National Institutes of Health test and time-resolved fluorescent immunoassay (TRFIA) in quantitative analysis, and had a better analytic performance than TRFIA. Therefore, the CLIA platform presented here may be important for application in modern vaccine quality control.

Nano-radiosensitizers provide a powerful tool for cancer radiation therapy. However, their limited tumor retention/penetration and the inherent or adaptive radiation resistance of tumor cells hamper the clinical success of radiation therapy. Herein, we report a synergistic strategy for potentiated cancer radiation/gene therapy based on transformable gold nanocluster aggregates loaded with antisense oligonucleotide-targeting survivin mRNA (named AuNC-ASON). AuNC-ASON exhibited acidic pH-triggered structure splitting from a gold nanocluster aggregate (around 80 nm) to gold nanocluster (

Non-gonococcal urethritis (NGU) is a type of urethritis that is transmitted by sexual contact. About 20%–50% of NGU cases are caused by Chlamydia trachomatis. Most NGU cases are asymptomatic, but failure to intervene promptly can lead to severe sequelae of the reproductive system and other complications. Here, we aimed to develop a technique to routinely screen for C. trachomatis infections to prevent such adverse consequences. The proposed approach involves the use of clustered regularly interspaced short palindromic repeats (CRISPR) RNA (crRNA) that is complementary to the cryptic plasmid fragments of C. trachomatis (i.e., the target sequence). In the presence of the target sequence, the RNase activity of the Cas13a protein is activated, and it cleaves a quenched RNA fluorescent probe such that fluorescence will be emitted. The proposed molecular diagnostic method based on the CRISPR-Cas13a technology leverages the high DNA-amplification efficiency of recombinase polymerase amplification (RPA) and the high specificity of crRNA. The sensitivity of the C. trachomatis-dsDNA detection based on CRISPR-Cas13a was 10 fM. A one-pot method based on CRISPR-Cas13a detection and qPCR was also developed. The results obtained by the two methods were closely correlated: χ2 = 81.798 based on a Chi-squared test (P < 0.001), κ = 0.975 based on a Cohen’s kappa test (P < 0.001), and the area under the receiver operating characteristic curve area was 0.991 (95% confidence interval: 0.970–1.000 P < 0.001) with a sensitivity of 0.982 (95% confidence interval: 0.890–0.999) and specificity of 1.000 (95% confidence interval: 0.863–1.000). Further, the method can be carried out at room temperature and yields results within 1 hour. The developed technique does not require expensive instruments and, thus, can meet the needs of community hospitals and other institutions for screening. Future research to develop lyophilized reagents could enable the application of this technique to point-of-care testing.

Ameliorated therapy based on the tumor microenvironment is becoming increasingly popular, yet only a few methods have achieved wide recognition. Herein, targeting multifunctional hydrophilic nanomicelles, AgBiS2@DSPE-PEG2000-FA (ABS-FA), were obtained and employed for tumor treatment. In a cascade amplification mode, ABS-FA exhibited favorable properties of actively enhancing computed tomography/infrared (CT/IR) imaging and gently relieving ambient oxygen concentration by cooperative photothermal and sonodynamic therapy. Compared with traditional Bi2S3 nanoparticles, the CT imaging capability of the probe was augmented (43.21%), and the photothermal conversion efficiency was increased (33.1%). Furthermore, remarkable ultrasonic dynamic features of ABS-FA were observed, with increased generation of reactive oxygen species (24.3%) being obtained compared to Ce6, a commonly used sonosensitizer. Furthermore, ABS-FA exhibited obvious inhibitory effects on HeLa cell migration at 6 μg/mL, which to some extent, demonstrated its suppressive effect on tumor growth. A lower dose, laser and ultrasonic power, and shorter processing time endowed ABS-FA with excellent photothermal and sonodynamic effects. By mild cascade mode, the hypoxic condition of the tumor site was largely improved, and a suitable oxygen-rich environment was provided, thereby endowing ABS-FA with a superior synergistically enhanced treatment effect compared with the single-mode approach, which ultimately realized the purpose of "one injection, multiple treatment". Moreover, our data showed that ABS-FA was given with a biological safety profile while harnessing in vivo. Taken together, as a synergistically enhanced medical diagnosis and treatment method, the one-for-all nanoplatform will pave a new avenue for further clinical applications.

The current protein interaction method is time consuming and cumbersome or the instrument is expensive. A new method that is convenient, fast, and high throughput needs to be studied urgently. The purpose of this study was to establish a homogeneous immunoassay to detect the interaction between insulin-like growth factor-1 receptor-β (IGF1R-β) and suppressor of cytokine signaling 1 (SOCS1). The recombinant vectors IGF1R-β/pENTER and SOCS1/pENTER were constructed and transfected into 293T cells. Based on homogeneous immunoassay technology, we established a suitable method. The signal intensity in the 293T lysate that overexpressed IGF1R-β and SOCS1, respectively, was compared with the signal intensity in the simultaneous expression of IGF1R-β and SOCS1. The interaction between IGF1R-β and SOCS1 was verified in vitro. The detection system for the interaction between IGF1R-β and SOCS1 was established. Compared with other methods, homogeneous immunoassay has the advantages of being rapid and sensitive, having higher sensitivity, and easy to operate. The interaction between IGF1R-β and SOCS1 was tested to verify the feasibility of this method and prove its practicability and sensitivity. This new method can be used as a high-throughput platform for protein-protein interaction, with the advantages of trace detection, short detective time, and high detective sensitivity.

Objective To evaluate the analytical performance of our previously developed chemiluminescence immunoassay (CLIA) kit for the detection of procalcitonin (PCT) and compare with the results obtained using the Vidas B.R.A.H.M.S. PCT™ test (PCT-V). Design and methods Our laboratory previously designed a novel CLIA kit and supporting instrument (AE-180) for the detection of PCT. We analyzed the clinical performance of this system, including the imprecision, limit of detection, and linearity of analyses of 305 serum specimens. The results were compared with measurements of the same serum samples obtained with PCT-V. Results The limit of detection and blank of our kit were 0.0075 and 0.0039 ng/mL, respectively. The intra- and inter-assay coefficient of variation of the kit were both between 0.8% and 3.9%. The equation of linearity was found to be y = 1.03× + 0.06 (r = 0.99) for concentrations in the range of 0.01–110 ng/mL. The correlation coefficient with the results of PCT-V was 0.995, and the equation obtained for Passing and Bablok regression analysis was 1.061 for our CLIA PCT kit and − 0.003 for PCT-V. Our kit slightly overestimated the concentration according to comparison with PCT-V results. Conclusion The kit that was previously developed in our laboratory for the measurement of serum PCT concentration using CLIA technology shows excellent performance, just that the functional sensitivity is not as good as the PCT-V; therefore, we suggest that this kit is suitable for clinical use.

RNA-binding proteins (RBPs) play important roles in regulating the expression of genes involved in human physiological and pathological processes, especially in cancers. Many RBPs have been found to be dysregulated in cancers; however, there was no tool to incorporate high-throughput data from different dimensions to systematically identify cancer-related RBPs and to explore their causes of abnormality and their potential functions. Therefore, we developed a database named RBPTD to identify cancer-related RBPs in humans and systematically explore their functions and abnormalities by integrating different types of data, including gene expression profiles, prognosis data and DNA copy number variation (CNV), among 28 cancers. We found a total of 454 significantly differentially expressed RBPs, 1970 RBPs with significant prognostic value, and 53 dysregulated RBPs correlated with CNV abnormality. Functions of 26 cancer-related RBPs were explored by analysing high-throughput RNA sequencing data obtained by crosslinking immunoprecipitation, and the remaining RBP functions were predicted by calculating their correlation coefficient with other genes. Finally, we developed the RBPTD for users to explore functions and abnormalities of cancer-related RBPs to improve our understanding of their roles in tumorigenesis. Database URL: http: //www.rbptd.com

Background/Aims: Oral squamous cell carcinoma (OSCC) is one of the most lethal malignancies worldwide and the most common type of oral cancer, characterized by invasive growth, frequent regional metastases, high recurrence, and poor prognosis. In the current study, we investigated the use of long non-coding RNAs (lncRNAs), tumor-specific growth factor (TSGF), and squamous cell carcinoma antigen (SCCA) as potential biomarkers for OSCC screening. Methods: LncRNA expression was measured by microarray analysis in three sets of OSCC and paired normal mucosal tissues. The potential lncRNAs involved in OSCC development were investigated by bioinformatics and verification experiments. We also determined the expression of these potential biomarkers in tissue and serum samples in a case–control study of 80 OSCC cases and 70 controls. Receiver operating characteristics, decision curve analysis, and the combined detection of lncRNA AC007271.3, TSGF, and SCCA were carried out to screen for OSCC biomarkers. Results: A total of 691 lncRNAs (433 upregulated and 258 downregulated) were differentially expressed in OSCC tissues compared with normal controls (p< 0.05). Based on Gene Ontology and pathway analysis, we selected four differentially expressed lncRNAs (AC007271.3, AC007182.6, LOC283481, and RP11-893F2.9), and showed that aberrant AC007271.3 levels in OSCC patients were significantly associated with clinical stage, especially in early-stage disease, in an expanded case–control study. The combination of AC007271.3 and SCCA (AUC=0.902, p< 0.001) showed significantly better ability to discriminate between OSCC and controls compared with SCCA or AC007271.3 alone. Serum AC007271.3, SCCA, and TSGF levels could also discriminate between OSCC and normal controls with sensitivities of 77.6%, 55.0%, and 63.3%, and specificities of 84.5%, 93.3%, and 66.7%, respectively. Conclusions: These results suggest that AC007271.3, SCCA, and TSGF could be novel circulating biomarkers for the determination of OSCC. However, further validation in large-scale prospective studies is necessary.

Background WAP four-disulfide core domain protein 2 (WFDC2) shows a tumor-restricted upregulated pattern of expression in ovarian cancer. Methods In this study, we evaluated the role of WFCD2 in tumor mobility, invasion and metastasis of ovarian cancer in clinical tissue and in ovarian cancer cells, both in vitro and in vivo. Results Our results revealed WFCD2 was overexpressed in ovarian tissues, and the expression level of WFCD2 was associated with metastasis and lymph node metastasis. Higher expression of WFCD2 was also observed in aggressive HO8910-PM cells than in HO8910 cells, and WFCD2 knockdown halted cell migration, invasion, tumorigenicity and metastasis in ovarian cancer cells, both in vitro and in vivo. Knockdown of WFDC2 induced the down-regulation of ICAM-1, CD44, and MMP2. Conclusion In summary, our work demonstrates that WFCD2 promotes metastasis in ovarian cancer. These findings suggest that WFCD2 plays a critical role in promoting metastasis and may constitute a potential therapeutic target of ovarian cancer. Electronic supplementary material The online version of this article (doi:10.1186/s13048-017-0329-0) contains supplementary material, which is available to authorized users.

Janus-activated kinase-1 (JAK1) plays an important role in many signaling pathways, including the JAK–STAT and SOCS pathways. The activation of the JAK1–STAT3 pathway is a key role in tumor inflammation and immunity by promoting inflammation. The detection of its interacting proteins is of great significance in many diseases. Although luminescent oxygen channeling is commonly used in immunoassay technologies, its use in the detection of JAK1 and interacting proteins has not been reported to date. We constructed eukaryotic overexpression plasmids pENTER–JAK1-His and pENTER–STAT3-His and, following single transfection and co-transfection, measured their expression by western blotting. Co-immunoprecipitation and luminescent oxygen channeling were then used to identify the protein interactions. JAK1 and STAT3 proteins were shown to be successfully overexpressed, and co-immunoprecipitation identified their interaction in vitro. We also detected protein interactions between JAK1 and interleukin 4 receptor (IL4R), JAK1 and growth hormone receptor (GHR). In conclusion, we verified that JAK1 and STAT3 interact in vitro using co-immunoprecipitation, and demonstrated for the first time the potential application of luminescent oxygen channeling for detecting JAK1 and its interacting proteins. Also we think this assay could help other researchers find unreported proteins that also have interactions in vitro.

Micropeptides (≤100 amino acids) are essential regulators of physiological and pathological processes, which can be encoded by small open reading frames (smORFs) derived from long non-coding RNAs (lncRNAs). Recently, lncRNA-encoded micropeptides have been shown to have essential roles in tumorigenesis. Since translated smORF identification remains technically challenging, little is known of their pathological functions in cancer. Therefore, we created classifiers to identify translated smORFs derived from lncRNAs based on ribosome-protected fragment sequencing and machine learning methods. In total, 537 putative translated smORFs were identified and the coding potential of five smORFs was experimentally validated via green fluorescent protein-tagged protein generation and mass spectrometry. After analyzing 11 lncRNA expression profiles of seven cancer types, we identified one validated translated lncRNA, ZFAS1, which was significantly up-regulated in hepatocellular carcinoma (HCC). Functional studies revealed that ZFAS1 can promote cancer cell migration by elevating intracellular reactive oxygen species production by inhibiting nicotinamide adenine dinucleotide dehydrogenase expression, indicating that translated ZFAS1 may be an essential oncogene in the progression of HCC. In this study, we systematically identified translated smORFs derived from lncRNAs and explored their potential pathological functions in cancer to improve our comprehensive understanding of the building blocks of living systems.

In rheumatoid arthritis(RA) pathogenesis, activated RA fibroblast-like synoviocytes (RA-FLSs) exhibit similar proliferative features as tumor cells and subsequent erosion to cartilage will eventually lead to joint destruction. Therefore, it is imperative to search for compounds, which can effectively inhibit the abnormal activation of RA-FLSs, and retard RA progression.3'3-Diindolylmethane (DIM), the major product of the acid-catalyzed oligomerization of indole-3-carbinol from cruciferous vegetables, has been reported to be functionally relevant to inhibition of migration, invasion and carcinogenesis in some solid tumors. In this study, we explored the anti-proliferation, anti-metastasis and anti-inflammation effects of DIM on RA-FLSs as well as the underlying molecular mechanisms. To do this, primary RA-FLSs were isolated from RA patients and an animal model. Cell proliferation, migration and invasion were measured using CCK-8, scratch, and Transwell assays, respectively. The effects of DIM on Matrix metalloproteinases (MMPs) and some inflammatory factors mRNA and key molecules such as some inflammatory factors and those involved in aberrantly-activated signaling pathway in response to tumor necrosis factor α(TNF-α), a typical characteristic mediator in RA-FLS, were quantitatively measured by real-time PCR and western blotting. Moreover, the effect of DIM on adjuvant induced arthritis(AIA) models was evaluated with C57BL/6 mice in vivo. The results showed that DIM inhibited proliferation, migration and invasion of RA-FLS in vitro. Meanwhile, DIM dramatically suppressed TNF-α-induced increases in the mRNA levels of MMP-2, MMP-3, MMP-8, and MMP-9; as well as the proinflammatory factors IL-6, IL-8, and IL-1β. Mechanistic studies revealed that DIM is able to suppress phosphorylated activation not only of p38, JNK in MAPK pathway but of AKT, mTOR and downstream molecules in the AKT/mTOR pathway. Moreover, DIM treatment decreased expression levels of proinflammatory cytokines in the serum and alleviated arthritis severity in the knee joints of AIA mice. Taken together, our findings demonstrate that DIM could inhibit proliferation, migration and invasion of RA-FLSs and reduce proinflammatory factors induced by TNF-α in vitro by blocking MAPK and AKT/mTOR pathway and prevent inflammation and knee joint destruction in vivo, which suggests that DIM might have therapeutic potential for RA.

Single nucleotide polymorphism (SNP) was associated with many human diseases, therefore, SNP detection was important for early diagnosis and clinical prognosis. Herein, a simple and accurate method for visual detection SNP sites (A/A, G/G, A/G) in CYP1A1 gene related to cancers based on colloidal gold nucleic acid strip biosensor and primer-specific polymerase chain reaction (PCR) was established. This method could directly distinguish SNP sites on strip biosensor by introducing twice PCR amplifications. The second PCR (primer-specific PCR) was performed using specific product of the first PCR as template, thus this twice PCR could reduce non-specific amplification greatly and obtain target product. In addition, single-strand or double-strand DNA (ssDNA or dsDNA) was accurately produced by introducing mismatched base at the 3’ end of forward primers in primer-specific PCR. The designed strip biosensor could only combine with the ssDNA, thus visual detection of SNP could be achieved within 10 min by color difference of a pair of strips. 61 human blood samples by this method were identical with those of pyrosequencing. This method had the advantages of rapid, visual and low-cost and was expected to be applied in medical diagnosis.

A sensitive, rapid and homogeneous reaction measurement method for quantitation of human epididymis protein 4 (HE4) in human serum by amplified luminescent proximity homogeneous immunoassay (AlphaLISA) was described. Built on a sandwich-type immunoassay format, analytes in samples were captured by one biotinylated monoclonal antibody combining on the surface of streptavidin coated donor beads, and "sandwiched" by another monoclonal antibody coated on acceptor beads. The coefficient variations of the method were lower than 10%, and the recoveries were in the range of 90-110% for serum samples. A value of 0.88pmol/l was identified as the minimum detectable dose of the present method for HE4. Compared with the results from electrochemiluminescence immunoassay kit (Roche) in 170 serum samples, there was a satisfied correlation coefficient of 0.984. The present assay demonstrated high sensitivity, wider effective detection range and excellent reproducibility for quantitation of HE4 can be useful for early screening and prognosis evaluation of patients with ovarian cancer.

Background Because of the life-consuming treatment and severe consequences associated with thalassemia, it is more effective to prevent than cure thalassemia. Rapid and sensitive detection is critical for controlling thalassemia. In this study, we developed a rapid and accurate test to genotype nondeletional α- and β-thalassemia mutations by an electrochemical DNA sensor. Methods Screen-printed electrodes were used as electrochemical transducers for the sensor, in which the capture probe DNA was attached to the golden surface of the working electrode via an S–Au covalent bond, which is highly suitable for immobilizing the biological element. In addition, two types of ferrocene with varying redox potentials for modified signal probe DNA were adopted. The hybridization signal is detected by alternating current voltammetry when the capture probe and signal probe hybridize with the target DNA. Results With this technique, 12 types of nondeletional α- and β-thalassemia mutations were detected, which constitute more than 90% of all the nondeletional types of thalassemia mutation determinants found in China, including the CD142 (TAA>CAA) Constand spring, CD125 (CTG>CCG) Quonsze, CD122 (CAC>CAG) Weastmead, −28 (A>G), Cap+1 (A>C), initiation codon (ATG>AGG), CD17 (AAG>TAG), CD26 (GAG>AAG), CD31(-C), CD41-42 (-CTTT), CD71-72 (+A), and IVS-II-654 (C>T) mutations. Concordance levels were 100% within the 20 blood samples of homozygous wild-type individuals and 238 blood samples of heterozygous mutant individuals. Conclusions The electrochemical DNA sensor developed here can be applied for rapid genotyping of thalassemia or other clinical genotyping applications and is useful for early screening of thalassemia in high-risk groups by minimizing the time and investment cost.

The isoenzyme creatine kinase MB is very important for diagnosis of acute myocardial infarction (AMI). Some CK-MB immunoassays are sensitive, accurate and available for clinical application, but they are expensive and time-consuming procedures. Furthermore, conventional fluorescence immunochromatographic assays (FL-ICAs) have suffered from background fluorescence interference and low analytical sensitivity. A rapid and simple FL-ICA with Eu (III) chelate polystyrene microparticles was developed to determine CK-MB in 50uL serum samples using a portable test strip reader by measuring the fluorescence peak heights of the test line (HT) and the control line (HC) in 12 min. The assay was reliable with a good correlation coefficient between HT/HC ratio and CK-MB concentration in samples. A linear range was 0.85-100.29 ng/mL for CK-MB, and the LOD was 0.029 ng/mL. The intra- and inter-assay coefficients of variation (CV) were both

Peng Li,1 Zhenhua Chen,1 Bing Liu,1 Kun Li,1 Hao Wang,1 Li Lin,1 Ling He,1 Jie Wei,2 Tiancai Liu1 1State Key Laboratory of Organ Failure Research, Institute of Antibody Engineering, School of Laboratory Medicine and Biotechnology, Southern Medical University, Guangzhou, Guangdong, People’s Republic of China; 2Department of Clinical Laboratory, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou, Guangdong, People’s Republic of China Purpose: Sepsis is a potentially fatal systemic body infection with a significant mortality rate worldwide. Although C-reactive protein (CRP), interleukin-6 (IL-6), and procalcitonin (PCT) might be biomarkers for sepsis diagnosis, PCT is more sensitive and specific than CRP or IL-6. We aimed to establish an efficient immunoassay that precisely detects PCT in human serum for the early diagnosis of sepsis. Materials and methods: We developed a novel amplified luminescent proximity homogeneous assay (AlphaLISA) for the quantitative detection of PCT in serum. In this assay, a pair of antibodies was used to capture PCT in serum and to form sandwich complexes after incubating for 15minutes at 37°C. Results: PCT concentrations were determined within a linear range of 0.016–100ng/mL. The limit of detection was 18.6pg/mL. The results demonstrate that the reproducibility, recovery, and specificity of this assay for PCT meet the requirements of clinical detection. The coefficient of determination (R2) between this method and commercially available enzyme-linked fluorescent assay (ELFA) kits was estimated to be 0.93045 in clinical serum testing. Conclusion: The novel assay for PCT detection was robust with high sensitivity and a broad dynamic range. Compared with conventional heterogeneous detection methods such as ELISA, this assay measured the concentration of the homogeneous form of PCT and provided results that are more accurate within a shorter detection time. We expect that this novel method will be useful for the early screening and prognosis evaluation of patients with sepsis. Keywords: sepsis, procalcitonin, nanoparticles, quantitative detection, homogeneous immunoassay

Alpha-fetoprotein (AFP), a primary marker for many diseases including various cancers, is important in clinical tumor diagnosis and antenatal screening. Most immunoassays provide high sensitivity and accuracy for determining AFP, but they are expensive, often complex, time-consuming procedures. A simple and rapid point-of-care system that integrates Eu (III) chelate microparticles with lateral flow immunoassay (LFIA) has been developed to determine AFP in serum with an assay time of 15 min. The approach is based on a sandwich immunoassay performed on lateral flow test strips. A fluorescence strip reader was used to measure the fluorescence peak heights of the test line (HT) and the control line (HC); the HT/HC ratio was used for quantitation. The Eu (III) chelate microparticles-based LFIA assay exhibited a wide linear range (1.0-1000 IU mL(-1)) for AFP with a low limit of detection (0.1 IU mL(-1)) based on 5ul of serum. Satisfactory specificity and accuracy were demonstrated and the intra- and inter-assay coefficients of variation (CV) for AFP were both

Enzyme-linked immunosorbent assay (ELISAs) specific for Epstein–Barr virus nuclear antigen 1 (EBNA1)-immunoglobulin A (IgA) are most commonly used in the clinical diagnosis of EBV infection. But they have a low sensitivity and the enzyme-labeled antibodies are unstable. In this study, a novel immunoassay based on an indirect time-resolved fluoroimmunoassay (TRFIA) was developed. Microtiter plates were coated with recombinant EBNA1. We used Eu3+-labeled anti-human IgA as probe. The precision, sensitivity, specificity, and stability were evaluated, and comparison with traditional and commercially available ELISAs was also made. The cut-off value for our TRFIA was 2.7. Intra- and inter-assay coefficients of variation for the TRFIA were 1.56–4.99% and 3.92–6.95%, respectively; whereas those for the ELISA were 4.54–8.16% and 7.07–10.52%, respectively. Sensitivity was obviously better than traditional ELISA when diluted positive samples serially. Additionally, stability, specificity test and comparison of sensitivity and specificity between the TRFIA and commercial ELISAs all proved satisfactory. In conclusion, the results demonstrated that EBNA1 IgA TRFIA was a sensitive immunoassay and had potential value in large-scale screening of human serum samples in developing countries. J. Med. Virol. 87:1940–1945, 2015. © 2015 Wiley Periodicals, Inc.

Objectives This study established a novel time-resolved fluorescence immunoassay (TRFIA) that allows the simultaneous determination of rubella virus (RV) IgM and cytomegalovirus (CMV) IgM in human serum. Design and methods Lanthanum elements labeled antibody and streptavidin–biotin system were used in the “capture sandwich” format simultaneously. Results The working range of TRFIA for RV IgM was 2–80 AU/mL and for CMV IgM was 5–400 AU/mL. Intra- and inter-assay coefficient of variation (CV) for RV IgM and CMV IgM were both less than 10% and recoveries were from 90% to 110%. No significant statistical difference in sensitivity or specificity was observed between dual-TRFIA and commercial chemiluminescent immunoassays (CLIA) in serum samples. Conclusion The novel dual-TRFIA for RV IgM and CMV IgM detection might have valuable clinical application, with satisfactory sensitivity, specificity and accuracy.

Quantitative hepatitis B core antigen (anti-HBc) measurements could play an important role in evaluating therapeutic outcomes and optimizing the antiviral therapy of chronic hepatitis B infection. In this study, we have developed a simple and rapid fluorescence point-of-care test based on a lateral flow immunoassay (LFIA) method integrated with Eu (III) chelate microparticles to quantitatively determine anti-HBc concentrations in serum. This assay is based on a direct competitive immunoassay performed on lateral flow test strips with an assay time of 15 min. The Eu (III) chelate microparticle-based LFIA assay could quantitatively detect anti-HBc levels with a limit of detection of 0.31 IU mL−1, and exhibited a wide linear range (0.63–640 IU mL−1). The intra- and inter-assay coefficients of variation for anti-HBc were both less than 10% and a satisfactory dilution test and accuracy were demonstrated. There were no statistically significant differences in sensitivity or specificity in serum samples between the Eu (III) chelate microparticle-based LFIA strips and the Abbott Architect kit. A simple, rapid and effective quantitative detection of anti-HBc was possible using the Eu (III) chelate microparticle-based LFIA strips. The strips will provide diagnostic value for clinical application.

Replacement of the in vivo rabies vaccine potency test (NIH test) by in vitro methods had been discussed by several researcher including WHO expert working groups. In this paper, a time-resolved fluoroimmunoassay (TRFIA) for the assay of rabies virus glycoprotein in rabies vaccine was first established to estimate the rabies vaccine potency by using specific monoclonal antibody that only recognized the native, trimeric and immunogenic form of rabies virus glycoprotein. Potency of the rabies virus glycoprotein was assayed with satisfactory performance under optimal conditions, and the method demonstrated satisfactory results when applied in practical samples. The correlation coefficient of potency values obtained from the present TRFIA and ELISA was 0.912, and 0.903 for those from the present TRFIA and NIH test. These preliminary results confirmed that this TRFIA can replace ELISA with higher performance, and could be a promising replacement of the NIH test. Based upon these results, the present TRFIA seemed to be a convenient tool for evaluating rabies vaccine potency and its products at different stages accordingly.

Tumor protein p53 acts as a trans-activator that negatively regulates cell division by controlling a set of genes required for cell cycle regulation, making it a tumor suppressor in different types of tumors. Because the transcriptional activity of p53 plays an important role in the occurrence and development of tumors, reactivation of p53 transcriptional activity has been sought as a novel cancer therapeutic strategy. There is great interest in developing high-throughput assays to identify inhibitors of molecules that bind the transcription-activation domain of p53, especially for wt p53-containing tumors. In the present study, taking MDM2 as an example, a novel amplified luminescent proximity homogeneous assay (AlphaLISA) was modified from a binding competition assay to detect the interactions between the transcription-activation domain of p53 and its ligands. This assay can be adapted as a high-throughput assay for screening new inhibitors. A panel of well-known p53-MDM2 binding inhibitors was used to validate this method, and demonstrated its utility, sensitivity and robustness. In summary, we have developed a novel protein-protein interaction detection immunoassay that can be used in a high-throughput format to screen new drug candidates for reactivation of p53. This assay has been successfully validated through a series of p53-MDM2 binding inhibitors.

Enzyme-linked immunosorbent assays (ELISA) specific for anti-HSV glycoprotein G (gG) are most commonly used in the clinical diagnosis of HSV infection. But most of them are qualitative and with narrow detection ranges. A novel time-resolved fluoroimmunoassay (TRFIA) methodology was developed for the quantitative determination of HSV IgG in human serum. The assay was based on an indirect immunoassay format, and performed in 96-well microtiter plates. HSV-1 and HSV-2 were used as the coating antigens. Eu3+-labeled goat anti-(human IgG) polyclonal antibodies were used as tracers. The fluorescence intensity of each well was measured and serum HSV IgG levels quantified against a calibration curve. The detection range of the novel TRFIA was between 5 and 500 AU/mL. Assay sensitivity was 0.568 AU/mL. The intra- and inter-assay coefficients of variation were 0.59–3.63% and 3.65–6.81%, respectively. Analytical recovery, dilution tests and serum panel tests were performed using TRFIA and the results proved satisfactory. There were no statistically significant differences in sensitivity and specificity between the TRFIA and commercial ELISAs. An effective, sensitive and accurate quantitative HSV type 1 and type 2 IgG TRFIA was successfully developed and provided diagnostic value in clinical use. Copyright © 2014 John Wiley & Sons, Ltd.

Sensitive, precise and rapid detection tests are needed in the quality control of rabies vaccine for rabies virus nucleoprotein. Previous studies for quantitation of rabies virus nucleoprotein focused on enzyme-linked immunosorbent assay (ELISA). A novel immunoassay for rapid determination of rabies virus nucleoprotein in rabies vaccine was first established by time-resolved fluoroimmunoassay (TRFIA). Based on a sandwich-type immunoassay format, analytes in samples were captured by one monoclonal antibody coating in the wells and "sandwiched" by another monoclonal antibody labeled with europium chelates. The immunocomplex was retained after washing, and then adopted treatment with enhancement solution; fluorescence was then measured according to the number of europiumions dissociated. Levels of the rabies virus nucleoprotein were measured in a linear range (5-2500 mEU/mL) with a lower limit of quantitation (0.95 mEU/mL) under optimal conditions. The repeatability, recovery, and linearity of the immunoassay were demonstrated to be acceptable. The correlation coefficient of nucleoprotein values obtained by novel TRFIA method and ELISA method was 0.981. These results showed good correlation and confirmed that this sensitive, precise and rapid TRFIA was feasible and could be more suitable for the quality control in the process of rabies vaccine production than ELISA.

Objectives Diabetes mellitus is a chronic disease affecting millions of people globally and resulting in significant death rates each year. A fast, inexpensive alternative to traditional testing and monitoring techniques is desirable, since secretion of insulin and C-peptide is impaired in diabetes mellitus. Design and methods A highly sensitive immunoassay was developed for the simultaneous measurement of C-peptide and insulin levels in human serum, utilizing dual-label time-resolved fluoroimmunoassay (TRFIA) and magnetic particle technologies. This assay was characteristic for a single-step sandwich-type immunoassay, wherein antibody-coated magnetic particles were used as the solid phase and Eu 3 + and Sm 3 + chelate labels were used for detection. Results Antibody-coated magnetic particles in a TRFIA format performed well in addressing a number of quantitative needs. Conclusions The results of this assay correlated well with commercial chemiluminescence assays and provided a number a advantages, including reduced sample volume, reduced reagent and personnel costs and reduced assay time, while maintaining the required clinical sensitivity.

A highly sensitive, rapid and novel simultaneous measurement method for cytokeratin 19 fragment (CYFRA 21-1) and carcinoembryonic antigen (CEA) in human serum by magnetic nanoparticle-based dual-label time-resolved fluoroimmunoassay was developed. On the basis of a sandwich-type immunoassay format, analytes in the samples were captured by antibodies coated onto the surface of the magnetic beads and sandwiched by other antibodies labeled with europium and samarium chelates. The lower limit of quantitation of the present method for CYFRA 21-1 was 0.77 ng mL−1 and CEA was 0.85 ng mL−1. The coefficient variations of the method were less than 7%, and the recoveries were in the range of 90–110% for serum samples. The concentrations of CYFRA 21-1 and CEA serum samples determined by the present method were compared with those obtained by the chemiluminescence immunoassay. A good correlation was obtained with the correlation coefficients of 0.961 for CYFRA 21-1 and 0.938 for CEA. This novel method demonstrated high sensitivity, wide effective detection range and excellent reproducibility for the simultaneous determination of CYFRA 21-1 and CEA, which can be useful for the early screening and prognosis evaluation of patients with lung cancer.

Background Rapid and comprehensive pathogen identification is crucial in zoonotic influenza diagnosis. Methods By optimizing the design of primers and probes and reverse-transcriptase polymerase chain reaction (RT-PCR) conditions, we achieved simultaneous detection of multiple influenza and zoonotic influenza viruses, including H1N1, H5N1, and H9N2 strains, in a one-step, quantitative real-time RT-PCR array (rRT-PCR array) of RNA from multiple influenza strains utilizing a single set of conditions for RT-PCR amplification. The target sequences from all targeted zoonotic influenza viruses were cloned into recombinant RNA virus particles, which were used to evaluate sensitivity, specificity, and reproducibility of the zoonotic influenza viruses RT-PCR array. Results The detection limit of the array was shown to be between 100 and 101 copies per reaction, and the standard curve demonstrated a linear range from 10 to 106 copies. Thus, the analytical sensitivity of this zoonotic influenza viruses RT-PCR array is 10–100 times higher than conventional RT-PCR. Specificity of the one-step zoonotic influenza viruses RT-PCR array was verified by comparison of results obtained with retroviral-like particles (RVPs), which contained RNA from isolates of seasonal influenza viruses, zoonotic influenza viruses, and other pathogens known to cause acute respiratory disease. Conclusion The high sensitivity, rapidity, reproducibility, and specificity of this zoonotic influenza viruses rRT-PCR array has been verified as being sufficient to detect the presence of multiple zoonotic influenza viruses in a single assay. The zoonotic influenza viruses RT-PCR array might provide rapid identification of emergent zoonotic influenza viruses strains during influenza outbreaks and disease surveillance initiatives.

Current clinically assays, such as enzyme-linked immunosorbent assay and chemiluminescence immunoassay, for hepatitis B surface antigen (HBsAg) are inferior in terms of either sensitivity and accuracy or rapid and high-throughput analysis. A novel assay based on magnetic beads and time-resolved fluoroimmunoassay was developed for the quantitative determination of HBsAg in human serum. HBsAg was captured using two types of anti-HBsAg monoclonal antibodies (B028, S015) immobilized on to magnetic beads and detected using europium-labeled anti-HBsAg polyclonal detection antibody. Finally, the assay yielded a high sensitivity (0.02 IU/mL) and a wide dynamic range (0.02-700 IU/mL) for HBsAg when performed under optimal conditions. Satisfactory accuracy, recovery and specificity were also demonstrated. The intra- and interassay coefficients of variation were 4.7-8.7% and 3.8-7.5%, respectively. The performance of this assay was further assessed against a well-established commercial chemiluminescence immunoassay kit with 399 clinical serum samples. It was revealed that the test results for the two methods were in good correlation (Y = 1.182X - 0.017, R = 0.989). In the current study, we demonstrated that this novel time-resolved fluoroimmunoassay could be used: as a highly sensitive, automated and high-throughput immunoassay for the diagnosis of acute or chronic hepatitis B virus infection; for the screening of blood or organ donors; and for the surveillance of persons at risk of acquiring or transmitting hepatitis B virus.

Background Cytokeratin 19 fragment antigen (CYFRA 21–1) is used to diagnose and monitor neoplasms. However, the main disadvantages of the currently available CYFRA 21–1 assays include heterogenous technology, being time-consuming, and having low through-put with low insensitivity. This study investigated the use of amplified luminescent proximity homogeneous immunoassay (AlphaLISA) for the quantization of CYFRA 21–1 in human serum. Methods The AlphaLISA kit was developed based on AlphaScreen detection technology with two different anti-CYFRA 21–1 monoclonal antibodies. One was coated on AlphaLISA acceptor beads and the other was biotinylated. Donor beads were coated with streptavidin. The test conditions were optimized and analytical performance was studied. Results The measurement range of AlphaLISA CYFRA 21–1 kit was 0.08–500 ng/ml. Assay detection limit was 0.08 ng/ml. The intra- and interassay coefficients of variation were 3.00–9.00% and 4.00–10.00%, respectively. There was no cross-reaction to alpha-fetoprotein (AFP), carcinoembryonic antigen (CEA), neuron-specific enolase (NSE), cancer antigen 19–9 (CA19–9), cytokeratins 8 (CK8), and cytokeratins 18 (CK18). The correlation coefficient of blood samples involved was 0.974 between CYFRA 21–1-AlphaLISA assay and a commercial electrochemiluminescence immunoassay (ECLIA) CYFRA 21–1 kit (Roche). Conclusions The AlphaLISA CYFRA 21–1 kit developed in this study had favorable performance characteristics for clinical application with acceptable analytical sensitivity, specificity, and accuracy.

Measurement of the free β subunit of human chorionic gonadotropin (free β-hCG) in serum is useful for prenatal screening. Concentrations of free β-hCG vary in different races. Conventional assays used for such measurements have limitations. We applied the AlphaLISA to measure levels of free β-hCG in maternal serum during 8-20 weeks of gestation in women from southern China. Two anti-free β-hCG antibodies were used: one was coated on AlphaLISA acceptor beads and the one was biotinylated. The assay also contained donor beads coated with streptavidin. The AlphaLISA assay detection limit was 0.11 ng/mL, and the analytical range was 0.11-200 ng/mL. The intra- and interassay coefficients of variation were 1.32%-2.50% and 3.44%-5.45%, respectively. The correlation with commercial Eu(3+)-labeled free β-HCG-TRFIA assay was good (y = 1.045x + 1.580, r(2) = 0.978). Median levels of free β-hCG in maternal serum at 8-20 weeks gestation were higher in women from southern China compared with those reported in women from other countries. The AlphaLISA for free β-HCG could become the assay of choice for applications in clinical diagnostics. The established median value of free β-HCG is helpful in clinical diagnosis specific for southern Chinese women.

A novel quantum dot-doped polystyrene nanoparticles-based lateral flow test strips (QPs-LFTS) system was developed to simultaneously detect a cytokeratin-19 fragment (CYFRA 21-1) and carcinoembryonic antigen (CEA) in human serum to aid the diagnosis and prognosis of lung cancer. Quantum dot-doped carboxylate-functionalized polystyrene nanoparticles (QPs) were prepared and introduced as fluorescent reporters in QPs-LFTS. The detection was based on a sandwich immunoassay and performed on lateral flow test strips, with an assay time of 15 min. The strips were read by a fluorescence strip reader to obtain the fluorescence peak heights of the test lines (HT) and the control line (HC). The ratio of HT/HC was used for quantitation. The QPs showed excellent photoproperties and good performance. Under optimal conditions, the QPs-LFTS system exhibited a wide linear range for CYFRA 21-1 (1.3–480 ng/mL) and CEA (2.8–680 ng/mL). The detection limits for CYFRA 21-1 and CEA were 0.16 and 0.35 ng/mL, respectively. The recovery and reproducibility of the method were satisfactory. Furthermore, excellent correlations (n =120, R2 =0.9862, P

In this paper, a novel time-resolved fluorescence immunoassay (TRFIA) is described that allows the simultaneous quantitative detection of hepatitis B virus surface antigen (HBsAg) and hepatitis B e antigen (HBeAg) in human serum to aid the diagnosis and monitoring of hepatitis B virus infection. The proposed method was developed based on a two-step sandwich immunoassay protocol in which monoclonal antibodies against HBsAg and HBeAg were co-coated in 96 microtitration wells, then tracer polyclonal antibodies against HBsAg labeled with samarium and tracer monoclonal antibodies against HBeAg labeled with europium chelates were used for detection. The detection range was 0.1–150 IU/mL for HBsAg and 0.5–160 PEIU/mL for HBeAg, and the detection limits were 0.03 IU/L and 0.09 PEIU/ml, respectively. The intra- and inter-assay coefficients of variation were below 8 % for both virus antigens. The dilution linearity and accuracy of the assay were satisfactory. No statistically significant differences were observed in sensitivity or specificity for the serum samples between the dual-label TRFIA and a commercial single-label TRFIA. These results demonstrate that an effective, reliable and convenient HBsAg/HBeAg dual-label TRFIA was successfully developed that may be clinically applicable for blood screening to monitor the course of hepatitis B virus infection and predict treatment responses.